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A
JOURNAL ~*~
OF
NATURAL PHILOSOPHY,
&
CHEMISTRY,
AND
THE ARTS.
VOL. XXXIIL.
Sustraten with Engravings,
DPPLIPP DIL DIG PP PPPS OL
BY WILLIAM NICHOLSON.
POEPLDAIELIOL IPS LIL OP OD
LONDON:
PRINTED BY G. SIDNEY, NORTHUMBERLAND-STREET, STRAND,
- For W., Nicholson, No. 13, Bloomsbury Square ;
AND SOLD BY
SHERWOOD, NEELEY, and JONES, Paternoster Row ; 3
and all Booksellers.
coe
1812.
PREFACE.
HE Authors of Original Papers and Communications
in this Volume, are J. A. De Luc, Esq. F. R.S.; Mr.
Thomas Reid, Edinburgh; Luke Howard, Esq.; Alfio
Ferrara, M. D.; William Hamilton, Esq.; Dr. Bostock ;
Dr. Marcet, F. R.S.; Mr. J. Singer; Messrs. Kerby and
Merrick; Mrs. A. Ibbetson; R. B.;*Mr. R. Porret, jun. ;
W- Nes Dr. Tuthill, F.R.S.3: Dr. Pearson,. F.:R. Si &c.3
John Trotter, Esq.; L.O.C.; Mr. F. Accum; Mr. Charles
Sylvester ; Lord Gray.
Of foreign Works, M. M. Hassenfratz; La Place; Tol-
lard Lelieur ; Le Bouvier des Mortiers; M. H. Klaproth;
_D’Arcet Dufaud; Vogel; Bouillon La Grange; Gay
Lussac; F. Peron; Thouin; Malus; Goering; Larrey;
Marcel de Serres.
And of British Memoirs abridged or extracted, Mr. J.
Allan; John Davy, Esq.; H.B. Way, Esq.; Rt. Hon.
Sir Joseph Banks, Bart. P. R.S. &c.; W.T. Brande, Esq. ;
W. H. Wollaston, M.D.; P. C. Boadie, Esq.; F.R.S.;
T. A. Knight, Esq. F. R. S. Pres. Hort. Soc.; Don Joseph
iv PREFACE.
Rodriguez; Dr. Wm. Roxburgh; Sir H. Davy, F. R.S. &c.s
Hon. H, Grey Bennet, Esq.; Mr, Tollard, Sen.
The Engravings consist of: 1. Sections of Plants to shew
the manner of the Buds in the Stalks, by Mrs. Agnes Ibbet-
son. 2. The secrét and open Nectaries of Flowers, by the
same. 3. An Apparatus by Messrs. Kerby and Merrick,
for measuring the sonoriferous vibrations of the Gases.
4, A Compensation Pendulum, by R.B. 5. An economi-
cal Lamp. 6. New disposition of Musical Keys, by J.
Trotter, Esq. 7. The Growth and Increase of Trees, by
Mrs, Ibbetson. 8. An Apparatus for manufacturing Prus-
sian blue. 9. Designs to illustrate the Structure of the
Roots of Trees, by Mrs. Ibbetson.
TABLE OF CONTENTS
TO THE THIRTY-THIRD VOLUME.
— eee ee
SEPTEMBER, 1812,
Engravings of the following subjects. Dissections of Plants, to show the
manner in which the Buds run up the interior of the Stalk, in Plants in
which it is annual ; by Mrs. A. [bbetson. In one 4to. Plate.
I. On the Interior Buds of all Plants. In a letter from Mrs, Agnes Ibbet-
son. — = =, - - - - - 1
II. An Account of some Experiments on the Combinations of different
Metals and Chlorine, &c. By John Davy, Esq. Communicated by Sir
Humphrey Davy, Knt. LL. D.; Sec. R. 5S. - - - 10
IIT. Meteorological Journal. - - - - - 22
IV. Chemical Researches on the Blood, and some other Animal Fluids. By
William Thomas Brande, Esq., F. R. S. communicated to the Society for
the improvement of Animal Chemistry, and by them to the Royal
Society. ~ - - - - - - +23
V. on the nature of falling Stars and the. large Meteors, in answer to Mr.
John}Farey, Senior. Ina Letter from Mr. G. J. Singer. - 33
VI. Sketch of the geology of Madeira; by the Hon. Henry Grey Bennet.
In a Letter addressed to G. B. Greenough, Esq. F.R.S. Pres.G.S. 37
VII. On the Decomposition of mites by Heat: by a Gay Lussac,
Mem. of the Institute. - Ad
VIII. Remarks on some useful Applications of Mstediotogical Observations
to Nautical Prophylactics: by F. Person, Naturalist of the Voyage of
Discovery to the Austral Lands, COL a of the Imperial Institute,
&c. | bad = - - 5
TX. Account of the Vicuna: by Mr. Larrey, Phybiotan in chief of the im-
perial Guard, one of the Inspectors General of Military Hospitals, &c. 66
X. Observations on the Hydrosulphate of Soda, and improving the prepa-
ration of the Soda of the eaeee's by iiss mipaler, pa of Chemistry
at Montpellier. - ‘ 7i
XI. An Essay on the Cultivation of the ep Bert by hd ene a Saxon
Agriculturist. - - 75
XII. Account of a Composition ee called Turkish Rose Pearls :_ by
Mr. Marcell de Serres, Inspector of Arts, at Vienna. - 78
XIII. On the tall Oatgrass ; by Mr. Tollard, sen. - - 79
Scientifi Ne ws. - - - ° - - 80
OCTOBER,
vi CONTENTS.
OCTOBER, 1812.
Engravings of the following Subjects: 1. Diagrams for explaining the ra-
diated figure of the stars and other luminous objects. 2 Figure to illustrate
the theory of Refraction. 3 An improved Circle of Keflection, by Mr. J.
Allan.
I. On the Electric Column, and ser) Bilectraicone- By J. A De Luc, Esq.
Lee - - - 81
Il. Effect of the Attraction between the weights and the pendulums on the
going of Clocks. Ina letter from Mr. Thomas Reid. - 92
III. An Essay on the apparent Figure of Stars and luminous Objects, seen
at a very great distance, and under a very, small Diameter. By Me. J. H.
Hassenfratz. - - - - is - 95
IV. On the double Refraction of Light in transparent ab Nitin By M.
Laplace. - - - - - - 104
V. Description of .a Reflecting Circle, in which the Screens can be readily
shifted in taking altitudes ; oe Mr, J. Allan, Blewitt’s Buildings, Fetter
Lane. - - - - - 112
VI. Meteorological Journal. - = - - - 118
VII. An account of some Experiments on the Combinations of different
Metals and Chlorine; &c. By John Davy, et commence by Sir
Humphrey Davy, Kt. LL. D., Sec. R. S. - 120
VIII. On the coral Fishery in the Sicilian Seas ; by Alfio Ferrara, M. D. 136
1X. Oa the medical Effects of the Bark of the Piscidia Erythryna of Lin-
nzus, or Jamaica Dogwood, Ina letter from William Hamilton, Esq. 145
X. A Correspondence between Dr. Bostock, and Dr. Marcet, on the subject
of the uncombined Alkali inthe Animal fluids. = - 147
XI. On the Culture and Preparation of Hemp in Dorcetshire, and on the
Growth of Sea Cale: By H. B. Way, Esq. = - - 151
XII. On the permed Chest Aina “mallee: eye) Mr. Tollard,
senior. 158
XIII. Notice from a Work of Monsieur Lelieur, on the hereditary
Diseases of Fruit Trees : by ss vere Hon. Bit oaeph Banks, Bart. K.
BD, ee Re Sy Bee A a - 159
Scientific News. < - - - . - ibid
NOVEMBER,
CONTENTS.
NOVEMBER, 1812.
Engtavings of the following subjects :—1. The secret and open nectary of
various Flowers, delineated from nature, by Mrs. Agnes Ibbetson.
2. An apparatus for measuring the soniferous vibration of the gases, by
Messrs, Kirby and Merrick. Compensation Pendulum, by R. B. Econo-
-mical Lamp. Construction of the Keys of Musical Instruments, by
John Trotter, Esq.
I. A Continuation of Experiments on the soniferous Vibrations of the
Gases, &c. by Messrs Kerby and Merrick. - hie 161
II. On the secret and open Nectaries of various Flowers. Ina Letter from
Mrs. Ibbetson. - - - - - - 171
III. Chemical Researches on the Blood, and some other animal Fluids. By
W.'T. Brande, Esq. F. R. S. Communicated to the Society for the ims
provement of animal Chemistry, and by them to the Royal Society. 179
IV. Remarkable Effects of the spontaneous Rise and Overflow of heated
Soap Lie in a metallic Pump. Ina Letter from R.B. with Remarks by
W.N.
- a é “ . z 189
V. On the Combination of Chlorine with oil of Turpentine. In a Letter,
from Mr. R. Porret, jun. - - - - - 194
VI. On the Electrical Effects produced by Friction between Bodies. In a
Letter from J. A De Luc., Esq. F. R.S. - ~ ~ 106
VII. Meteorological Journal - - - - - 206
VIII. On the primitive Crystals of Carbonate of Lime, Bitter-Spar, and Iron-
Spar. By William Hyde Wollaston, M. D. Sec. R. S. - 208
IX. Account of an Economical Lamp for producing heat, with a considerable
saving of oil.. In a Letter from a correspondent, L. O.C. sion Qk
X. Description of a new Construction and Arrangement of the Keys of
Musical Instruments, invented by John Trotter, Esq. (W.N.) 215
XI. A new Compensation Pendulum, without joints or surfaces bearing
against, or moving upon.each other. Ina letter from a Correspondent.
(R.-B.) - - - - - > - 217
XII. Abstract of an Essay on the Construction and Effects of the Pneu-
matic Tinderbox, by Le Bouvier Desmortiers. - - 220
XIII. Analyses of Minerals... By Martin Henry Klaproth, Ph. D. &c. 228
Scientific News.—Crystallographic Models, exhibiting the forms of
, Crystals, their production, geometrical structure, transitions of forms —
and mechanical dissections. Intended to illustrate she science of Crys-
. tallography, after the method of Hatiy. Accompanied with a treatise
elucidating the elements of that branch of knowledge. By Frederick
Accum. M. R. I. A. Operative Chemist and Lecturer on practical Che-
mistry, and on Mineralogy and Pharmacy. - - = 237
Notices, &c. to Correspondents, Queries by Inquisitor. - 240
DECEMBER,
Vili CONTENTS.
DECEMBER, 1812.
Engravings of the following Subjects: The Growth and Increase of Trees.
By Mrs. Agnes Iibbetson. Apparatus for the Manufacture of Prussian
Blue. ; .
I. On the Growth or Increase of trees: by Mrs. Agnes Ibbetson. 241
II. Some Horticultural Observations, selected from French Authors.’ By
the Right Hon. Sir Joseph Banks, Bait. K. B, P. R.S, &e. - 251
iI. Farther Experiments and Observations on the Action of Poisons on the
Animal System. By B.C, Brodie, Esq. F. R.S. Communicated to the
Society for the Improvement of Animal ices roile and by them to the
Royal Society. - > - - - 258
IV. Description of an Apparatus by means of which all bad Smell may be
avoided in manufacturing Prussian Blue: by Mr. d’Arcet. - 268
VY. Extract from a Letter addressed to Mr. d’Arcet by Mr. iene: Director
of the Iron Works at Montalaire, near Creil. - 27%
VI. On the liquid Sugar of Starch, and the transmutation of sweet Sub-
stances into fermentable 5 Sugar, by 3 Mr, vorel. ion by, Mr. Bouillon-
Lagrange. - - 274
Vil. Abstract of a Paper on the Deliquescene of Boles ; by Mr. Gay
Lussac, - - - - 282
VIII. Remarks on the Correspondence between Dr. péetiee and Dr.
Marcet, on the subject of the uncombined Alkali in the animal Flaids,. In
a Letter from George Pearson, M. D. F. R. S. &c. - - 285
1X, On Hygrology, Hygrometry, and their connexions with the Phenomena
observed in the Atmosphere, By J. A. De Luc, Esq. F. R.S. 221
X. Meteorological Journal, — ° - - - - 304
XJ. On the Nature and Detection of the different metallic Poisons. In a
Letter from Mr, Charles Sylvester. - = - 306
XII. On faciliating the Emission of Roots from Layers. By T. A. Knight
Esq. Pres. H. 8. - - - - - - 314
XII. On the Cultivation of the Jamrosade (Eugenia Jambos L,) in the
Wational Garden at Paris, abridged from the account given by M. Thouin;
™m the Annales du Museum, Y. 1, pi Sey; sie Richard Anthony
Salisbury, Esq. F. R. S, &e. - - + 315
XIV. Letter from Dr. Tathil on the Sugar from Potatoe Starch. - 319
Scientific News, * - o = = - 32@
sUP-
CONTENTS. ix
SUPPLEMENT TO VOL. XXXTII.
~«
Engraving on the following Subject: Illustration of the Structure of the
Roots of Trees. By Mrs. Agnes Ibbetson.
I. Observations on the Measurement of three Degrees of the Meridian, con-
ducted in England, by Lieutenant-Colonel William Mudge. By Don
Joseph Rodriguez. Fram the Philosophical Transactions for 1612,
p. 321. = : : - - - 325
II. On the Roots of Trees, By Mrs. Agnes Ibbetson. - - 334
III. Popular Statement of the beautiful experiments of Malus, in which
he has developed a new property of light. - - - 344
IV. Some Account of the Teak Tree of the East Indies. By Dr. William
Roxburgh. - a - - - - 348
V. On some Combinations of Phosphorus and Sulphur, and on some other
Subjects of Chemical Inquiry. By Sir Humphry Davy, Kt. LL. D.
Sec, R. S. = Py = « = a 354
Scientific News. a * in ” ™ = 362
Bet ; A JOURNAL
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Michoteons Philos. Journal Vel AXXUIPLT jr, 7,
AN
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A
JOURNAL
“OF
NATURAL PHILOSOPHY, CHEMISTRY,
AND
THE ARTS.
SEPTEMBER, 1812
ARTICLE I.
On the Interior Buds of all Plants. Ina Letter from Mrs.
| AGNES IBBETSON.
To Mr. NICHOLSON,
SIR, ie AF
AVING shown in my last-letter his the various parts
of a stem finish in a flower, and I think proved, in the most
absolute manner, that each part of a flower is formed by an
‘appropriate part of the stem, peculiarly or separately dedi-
cated to its formation, I shall now turn to the middle of a
plant, and give as complete a picture as I have been able to
discover of that part, with the various changes produced
in it by the manner in which the buds run up the interior
of the stem, in all plants whatever, that shoot their bud each
year from the root; and the stalks of which grow yearly Plants that
_ from the ground; whether perennial or biennial, whether Pekin ny
dying down or fresh sown. The plants which are the sub- j
ject of the present letter will embrace an amazing class; for
_ after the strictest search, and most exact dissections, I can
discover only five sorts or divisions in nature, comprising
many classes and orders, and which, from their consequence
Vou. XXXIII, No. 151.—SEpr. 18126 B and
ete ee
The bud
shoots in five
different
modes, form-
* ing so many
natural divi-
sidus of plants.
Manner of
shooting the
bud in trees,
Ec,
ON THE INTERIOR BUDS OF ALL PLANTS. \
:
and paucity of numbers, may perhaps well deserve to form
the foundation of a natural method, and open to us that
which nature herself designed as the commencement of such
aplan. I shall first give the five different manners of shoot-
ing of the bud, and then enter into farther details concern-
ing this important subject.
Ist. All these plants which shoot their bud from the
nearest line of life, whether in branch or twig: as trees,
shrubs, and semishrubs.
ad. All those plants that rise from the earth each year,
having a new stem, let their real existence be long or short,
and that shoot their bud from the root.
3d. The plants that have no flower stem, but that have in’
its stead a rallying point, which is immediately discovered
by a band or knot; from which the flower buds proceed,
aud which is found only in grains and grasses.
4th. Those plants which have no regular flower stem, but
which are divided from the last by shooting a few partial
vessels, with the line of life, just before flowering, enclosing
the flower buds: bat which are all concealed together bathe
in the cuticle of the leaf: as ia the palms, arums, and all
plants having grass leaves, without bands or bulbs.
5th. All plants that shoot their buds from a bulb.
These five collections of plants are all I can gather
from the most exact examination and dissection of British
as well as exotic plants; and it appears to me to lay open
that view to the discovery of the system of naturel have so
long and so ardently sought. But this subject I shall enter
into more fully when better prepared to give satisfaction to
the public; at present I shall confine myself to the shooting
of the bud in the stem of plants.
Of the Ist example, or manner in which buds shoot in
trees, shrubs, and semishrubs, I have already given many
descriptions: it isas beautiful a process as nature presents :
that se soft, so tender a being, should pass through so hard a
substance unhurt, that-by the moisture of the pith (retained
for the purpose) the wood should be separated into collec-
tions of vessels, and made to bend both ways, so asto form .
# covered way for the bud, that it may pass in the midst, un-
pressed and unconfined, isa conception that the view of the
specimen
ON THE INTERIOR BUDS OF ALL PLANTS.. 8
specimen alone could prove the truth of; but itis so easily
seen, that it requires only to strip the bark from a branch of
any tree, and plenty of buds will be found just shooting from
the tuterior, making their way through the hard substance,
It can never be mistaken by a careful observer for that harsh
and diminutive piece of wood, which, when the bark is taken
off, appears as passing to each leaf; for this is hard, but the
buds are always found at the end, very soft and succulent,
aud covered with albumen. .
To the 2d example I shall now turn, namely, that in Shooting of
which the buds shoot each year from the root, and the stem ini be
is but aunual, let the root be older or not. This fora long hic deaaly
time puzzled me beyond measure, and few will conceive the from the earth,
labour the discovery has cost me, and the quantity of herba-
ceous and anaual plants I have dissected before I could
perceive the whole truth. Perhaps it even exceeds in
beauty and contrivance the shooting of the buds in trees,
Thad long been convinced, that the bud shot from the root,
but except in those plants where it runs across the pith,
and where I had traced it occasionally up the wood vessels,
I could not discover what became of the buds, after they
had disappeared at the beginning of the stem, till I found
them again in the axilla of ‘he leaves. I shall now teke a
pentandria digynia plant, and show the whole process of its
growth.
I have already said, that the bud is formed in the interior of
the root of annual plants, or such as die down tothe ground
every year; and shall now show how it continues its way in
those plants that cross the pith, and then proceed to the buds
that do not cross it. The best way of dissecting for both
these purposes, is to take along succession of plants, each
a few days or a week older than the preceding. The altera-
tion this little time produces in the interior is amazing.
Taking a very young heracleum spondylium ; the prepara- Formation of
tion for forming these immense leaves are all that appears pa ae
at first in the plant; and thisis al’ confined to the bark only, ac haa
which it enlarges, The leaves differ in some measure in
their manner of forming from the leaves of trees and shrubs,
though they are equally woven: no part is more indebted
to those occasional hairs (mentioned in a former letter) than
B2 the
Buds pass
through the
wood vessels,
ON THE INTERIOR BUDS OF ALL PLANTS,
the leaves of this plant. As soon as the midnb of the leaf
iscompleted, and the quantity of vessels for weaving the
first row of the cross work of the leaf is finished; it is all
rolled together into a spike, and this spike is surrounded by
immense hairs, as shown at AA, fig. I, PI. I. (BB repre-
sents one of the hairs much magnified). These soon draw
plenty of moisture to mix with the juices to form the pabu-
lum of the leaf. The hairs then disappear, the part unrolls,
and the leaf begins to weave itself, as at C D, fig,2. All
this time the root is plain and simple, and the pith of the
stem (though frequently crossed by the line of life) showing
nothing beside, but its own original figure; and though but
Te tne part of the stem is yet “formed, it is RUPE with
all its forces, and juices, in rolling and unrolling the leaf.
But no sooner is the weaving of the leaf finished, than the
shooting of the bud in the root begins; the khots are soon
formed on the line of life, within the centre of the root; the
ends break, and two buds shoot from each knot; they
pass through part of the wood in the root, and then disap-
pear; for each row of bud has its appropriate wood vessels,
up which it then passes. It should seem, that all the pen-
tandria digynia plants appear to have too much flower for the
wood vessels to contain, nature therefore has recourse to an
expedient of a very curious kind: the pith is divided into
compartments by the line of life; and at each compartment
the buds are pressed out of the vessel, and ranged across the
plant. All che pentandria digynia tribe are umbelliferous,
and shoot at different times (but at very short intervals) small
collections of flowers. It will be seen therefore, that nature
already prepares them for the purpose ; dividing them in the
stalk as’ they are to shoot. With what art, what exquisite
beauty, nature has managed to keep the pith still in the
middle of the stem, in order to retain that moisture neces-
sary to the shooting such a quantity of buds; and yet con-
trived to secure ety of room for those buds to spread,
and come to perfection: ‘dividing the stalk in umbels as
they are afterward to shoot into flowers! See fig. 2, E, F, G,
the different divisions ; H fhe line of life: I the pith. When
the buds were in the root, they were scattered in a careless
mauner; and moving in the same'direction as they do in the
‘ wood
ON THE INTERIOR BUDS OF ALL PLANTS. §
wood of trees, that is horizontally. The wood therefore
made way forthem. But no sooner do they begin to run up
the stem, than the wood vessels instead of forming a covered
way for them, opens and receives them within their aper-
tures. A picture of one of the vessels extremely magnified
will give an idea of their formation, see fig. 3: K K are the
vessels through which passes the sap; L the interior vessels
containing the buds; M the albumen, which always appears
above and round the buds. All the buds are tied together Buds distin-
as in seeds, see fig. 4. The sap vessels, though forming Shae tle
only a part of the new cylinder, are much larger than in the leaves.
trees. When the buds rise to the top of the stem or axilla
of the leaf, where they are to flower, several of the squares
join together, and form one sort of flower bud ; which after-
ward divides into umbels,
But all the plants that shoot their buds from the root, and All buds shoot- ¥
have flower stems, have not their buds crossing the stem Sarit
in this manner, In the greatest number of herbaceous cross the stem
plants, the buds runs up the interior of the wood _ yessels to an this DANNEYe
the place where they are to show themselves; that is, to the
top of the plant, or the axilla of the leaf: and are not seen °
till they get there, Yet take a pretty thick cutting of any
of these plants, and keep it a few hours, and you will see the
buds crowing out of the vessels exactly as the buds of silver
or feat grow in the arbor diane, or saturni under your eye.
It was by. such a piece of the plant that I discovered how
the buds crept up the interior of the wood vessel, and re-
mained so long concealed.
‘I shall now turn to the third division, which embraces Bud, how
: grain and grasses of every kind, that possess the peculiar formed i in grain
band or oe which is perfectly unlike every other con- he i
trivance in the vegetable world. It exceeds indeed any yet
shown; but I fear that at every new proof of this exquisite
performance, one must have neither soul nor feeling not to
become an enthusiast on the subject, when contemplating
such wonders ; beholding such astonishing productions. As
there is no stalk properly so called, the ditlerent parts of the
plant are collected 1 in the flat leaf of the grass. Thus the bar k,
the inner bark, the wood, and the line of life, are all possessed
of stripes in the leaf. How then can the two sorts of buds
. be
Formation of
the bud in
grain,
Use of the
knot in grain
And grass:
ON THE INTERIOR BUDS OF ALL PLANTS. -
be protruded ? by all the different parts meeting in a band,
when a collection of each matter is selected to produ e the
circle of the leaf buds, and form a new leaf. Few operae
tious can be more plain and easily understood than this part
of the process; it is attended with an odd kind of cone
trivance, which shows that nature often makes use of the
same means we do to effect the same purpose. When the
part is to be selected to form the leaf bud, the rest ix tied —
with a knot, lest it should tear down or unravel (see oo tig.
5). Then the vessel selected rises, and soon produces a
bud, and when the whole row is completed they join toge-
ther and form a new leaf auder the other: this ts repeated
three times, but at the fourth knot, when the leaf is produced,
it is formed round instead of flat, aud a quautity of albumen
is generated by the stopping of the sap. The line of life
then strikes out of the edge of the leaf, and forms a broad
circle in the interior of the band, which is always a fore~
runner of the bud; immediately knots appear on the line,
they break, and the flower buds are seen shooting from the
ends; their numbers soon fill the round leaf: the buds are
all tied together by the line of life as in seeds, and remain
tn their enclosure till they are perfectry ready to shoot out
at the top of the plant in a spike of grassy flowers, Thus
this band or railying point not only serves to strenghthen
the plant and support it, but gives a new way of forming
the leaf buds, and of protruding the flower buds; and this
is no work of imagination, as I shall now show. Fig. 5 is the
part selected to form a new leaf bud. Fig, 6 is the first
shooting of the flower bud ; and though there is some little
part of the mechanism J do not quite understand, still as far as
I have described, what with watching and dissection, 1 am
pretty certain of being right, and not misleading those who
will venture to follow me. That the flower bud is merely
the embryo of the plant, enclosed by a few seminal leaves,
and is not covered by the meal till the flower rises as high
as P, is a certain truth, since I have dissected them both
before and after. That the flour of corn, or meal, is
formed of the inner bark juices alone, I have the most po-
sitive proof; since it is only in the inner bark vessels it is to
be found, even from the root: at each new band it grows
7 more
ON THE INTERIOR BUDS OF ALL PLANTS, rd
more like wheat, and when the fourth knot is perfected the
meal is quite milky and sweet to the taste; and when the
embryo is ready to be covered by it, as at P, it is the vessels
PP that convey the meal to the embryo, when }t is little conveying the
more than very thick milk, which soon however hardens oe
when spread on the embryo, and when the buds next appear
they are covered by it, though before absolutely destitute of
it. As in every other flower, each part is produced by its
own appropriate matter: the male by the wood, the female
by the line of life ; the bark produces the scales, and the
inner bark the meal. Thus all concur with other plants to
show the truth of that fact. All grain as well as grasses are
alike in their formation, they differ only in the quantity of A little dif-
meal with which their seeds are covered: there is however ac ti ape
in the grasses some little difference in the mechanism, but grasses.
not worth mentioning.
Though a digression I cannot help here giving a piece
of information, which appears to me of no little consequence.
We suppose that seed to be the finest for producing wheate
flour, which has on it the greatest quantity of meal. I have
repeatedly tried the experiment, and two gentlemen have also
essayed the same ; to sow a part ofa field with refuse wheat, it wheat
provided the seed is perfect. The difference of product be- was pte
tween this and the finest and largest seed that could be pro-
cured was not to be discovered. Provided the embryo is
strong, the quantity of meal on it signifies little; for the
best covered is certainly not the strongest producer. In
dissecting wheat I have always found that seed with the
largest star or hilum gave the greatest returns, and not the would save us
one most covered with meal. Much care should be taken ™UCh flour.
to choose seed from a field where there has been no smut,
no corn cryptogamia, and to prefer seed not taken from a
thrashing machine, or lime and sand floor, for they all in
some measure injure; the first two indeed to a great degree:
but its being only thin of flour is far from being against it,
on the contrary, the embryo is often the stouter for it.
Nature keeping the embryo such a time without meal is
surely a hint to us, and shows that it does not strengthen
the plant.
I now turn to my fourth example evinced in the palms, 4, example.
. arums,
The buds
mounti.g in
bulbous
plants.
Decreasing of
the stems in
breadth.
ON THE INTERIOR BUDS OF ALL PLANTS.
arums, callze, and dracontia. These have been arranged
with grain avd grasses; but they are extremely different in
their formation. ‘Though they have (like the grasses) no
apparent stem; yet they send their buds from the root just
before flowering; by enclosing them in wood vessels, the ~
buds being tied together by the line of life ; and this slender
piece running up within the cuticle of the leaves unperceived
till it strikes out of the axilla, or bosom of the leaf, in a
bunch of flowers. But it is very easily detected by dis-
section, if sought; J have repeatedly taken it out of its place
of concealment after watching its progress from the root.
So careful has nature been to separate this collection from:
the leaf; that there is a double cuticle on the way up for the
purpose; and I suppose to prevent the contamination of
the juices. Salf tis
In the 5th example, that is in all bulbous roots, the ide
are known to be formed in the root, and to rise by degrees
improving till they show themselves perfect flowers at the
top of the plant, merely by the lengthening of the peduncle :
but no person ever suspected, that this was a repetition ‘of
the case of al) those plants which rise yearly from the earth;
that they:all equally draw their buds from the root, and pass
it to the top, im the interior of one or many wood vessels,
according to the sort or size of the flower,’ In the ranun-
culus tribe the floweriis so complete, (even ‘in the root) that
I have taken it out,-and dissected it, and proved that the
‘seeds are already formed in it.) The various parts of | the’
flower of a bulb are all formed; itvis only the proportions
that are not observed in its earlier state. lt is a curious
truth, that certain parts, as the stamen, germe,-and nectaries,
are much larger when first forming, than they are when
more thoroughly perfeeted. As to the offsets of a bulb they
are merely a second sort of bud; with all the attendant parts
the same ; or another sort of seed ; for the difference between
these parts is very trifling, all equally proceeding from a
‘knot in the hue of life, »
I have thus given an account, as I promised, of the five
dirigions, wmich miybt well form the foundation of a natural
method: as a more important point in physiology than the
budding « of plants could not well be found, or fixed on for
the
ON THE INTERIOR BUDS OF ALL PLANTS. S
the purpose. I shall now take notice of an observation, that
was one of the first I made when examining herbaceous
plants, and dissecting them; ** The increase in breadth of
*< the stems of those plants at a certain time of their growth.”
It is now accounted for by the running up of the buds, as
this must of course enlarge them: it however puzzled me
not a little to comprehend, why all plants, that rose yearly
from the earth, should deerease so much when coming out
into flower; especially as they must at that time require more
rather than less sap. But the discovery of the buds solves
the whole mystery : the flower being within the piant takes
nearly the same quantity for its support, and the increase of
the stem falls wholly on the interior buds, which most natu-
rally accounts for it. I shall now close this long letter with
a few words on dissections in general.
Will it not appear by the specimen of the heracleum Op dissections
spondvlium, fic. 2, how very difficult it is to dissect plants, in general.
and how necessary it is to take them so as to become ac~
quainted: ‘with their continual variations, which are still
greater within (if possible) than at the exterior? how impos-
sible that a person, who only dissects a plant a few times,
should understand it? I may say without the smallest ex-
aggeration, that several persons might give a picture of the
dissection of the same part of a piant; and each might ac-
cuse his neighbour of giving a false delineation, and yet each
drawing might be just and true; but taken at various sea-
sons, or different ages of the plant. Mirbel has given many
excellent specimens much magnified ; but insome not keep-
ing to the right cylinder his pipes do not join, and: appear
therefore placed for nothing. Nature acts not in this manner:
all is consistent and useful; and that use most apparent and
easy to be understood, if the plant is properly cut. To dis-
sect a plant rightly, so as to produce specimens that will
truly explain the nature and habit of a plant, is no easy
thing; for it requires the most perfect knowledge of its dif-
ferent parts; which is only to be acquired by long study
and constant dissection, The ist point requisite is to be at~
tentive to keep to the right cylinder, particularly if you mean
to halve it ; as at fig. 2, for if you do not divide it properly,
you will have the back of the bud in one square; the front in
another ;
10 COMBINATIONS OF OXIiMURIATIC ACID AND METALS.
another ; and no bud in athird. In short, instead of that
regularity of figure with the line of life leading up to each
bud as in fig. 2, all will be confusion and disorder. I never
On the instru- diyide a plant without first marking it with ag instrument.
aie I use almost as many different sorts as a surgeon: to separate
the cylinders requires a very sharp and cutting instrument,
and Tam at last driven to the necessity of inventing and con-
triving my own. ;
I noticed above the having frequently found instances,
where nature makes use of the same means we should our-
selves have had recourse to in the same predicament: and
some have expressed surprise atit. But why should we be
astonished? whence proceed the ideas of man, but from the
suggestions of that Creator whose works we are studying? Is
it strange then, that we should find them alike; when pro-~
ceeding from the same source? The works of nature are-
certainly infinitely more perfect; and if we studied them
with stricter attention, ours would borrow more of that beau-
tifal simplicity, which so adamirably distinguishesthem. Still
both proceed from God alone ; though our notions and ideas |
are so contaminated with the feebleness of man’s nature.
I am, Sir,
Your obliged servant,
AGNES IBBETSON. :
Fig. 6, the first passing up of the flower buds, or rather
‘the embryo, as Q, to form the flower at PP.
Fig. 7 a horizontal section of the wheat in the middle of
the fourth knot or band; where the embryo is generated on
the line of life, throwing oni two buds at each end ; see RR.
SS are the bark vessels which form the meal.
$$$ ____—_—-- a -
Hl.
An Account of some Experiments on the Combinations of dif-
Jerent Metals and Chlorine, &c. By Joun Davy, Esq.
Communicated by Sir Humpnry Davy, Knt., LL. D.;
Sec. R. S*. |
Introduction.
Sapeipticn + My brother, Sir Humphry Davy,. appears to me to have
oO . é . .
acid -imilar co demonstrated, in his last Bakerian Lecture, the existence of
guides, * Philos. Trans, for 1312, p. 169, a class
COMBINATIONS OF OXIMURIATIC ACID AND METALS: 11
a-class of bodies similar to metallic oxides, and consisting of
metals in anion with chlorine or oximuriatic acid.
These combinations are the principal subject of the fol
lowing pages. I shall do myself the honour of giving an ac-
count of the experiments I have made to ascertain the pro
portions of their constituent parts, and likewise of describing
some that have not. yet been noticed.
Ishall have to relate also the attempts I have made to ase Doctrine of
certain the proportions of sulphur in several sulphurets, and wan da
the experi ments I have performed to estimate the quantity
of oxigen in some metallic oxides. The general analogy of
definite proportions led me to both these undertakings. This
analogy, it will be perceived, I have constantly kept in view,
and have had recourse to, both for detecting inaccuracies in
my own experiments, and in considering the results of the
experiments of others.
As the nomenclature connected with the old hypothesis New nomen-
respecting oximuriatic acid is inconsistent with the new views “lature.
of this substance, I shall venture to call the compounds of —
the metals and chlorine to be treated of, by the names which
my brother has proposed for them.
1. On the Combinations of Chlorine and Copper, &c.
There are two distinct combinations of chlorine and cop- Oximuriatic
per, both of which may be directly made by the combustion 845 combines
with copper in
of this metal in chlorine gas. When the gas was admitted two propor
inte ‘an exhausted retort containing copper filings, the filings tions.
became ignited, a fixed fusible substance quickly formed,
and the interior of the retort soon became lined with a fine
yellowish brown sublimate. The former substance evidently
_ contains least chlorine, for when it was heated alone in chlo-
Fine gas, it absorbed an additional portion, and was converted
into the latter. Hence the fixed compound may, in confor-
mity with the principles of Sir Humphry Davy’s nomen-
elature, be called cuprane, and the yellow sublimate,
cupranea,
Cuprane may be procured in several other ways. It may 1st compound;
be obtained by heating together copper filings and corrosive tee
sublimate ; and it was thus first discovered by Boyle, who
ealled it resin of copper, from its similitude to common re-
sine
12
Another mode
ef obtaining it.
Proust’s white
ruuriate of
LAPPere
Properties.
of this
compound.
20 compound.
How procured,
COMBINATIONS OF OXIMURIATIC ACID AND. METALS.
sin. Two parts of corrosive sublimate, and one. part of
copper filings, I have found the best proportions of the maz.
terials. :
It may be obtained by boiling copper filings in murtatic.
acid, or by exposing slips of copper partially immersed in
this acid to the atmosphere. In the last instance, I have
found the changes connected with the formation of cuprane.
rather complicated ; the copper exposed receives.oxigen from
tbe atmosphere, and acid from the ascending muriatic acid.
fumes, and isthus converted into a green insoluble salt, and
this, absorbing more muriatic acid, slowly passes into the.
deliquescent muriate, which flowing into themuriatic acid is
changed by the action of the immersed copper inte cuprane.
Mr. Proust, the first modern chemist who examined cu-
prane, and who 1s commonly considered as the first discoverer
of this compound, found it produced by the action of muriate
of tin on muriate of copper; he named it white muriate of
copper, and ascertained that a similar substance results from.
the decomposition of the common deliquescent muriate by
heat.
Cuprane, by whatever means prepared, possesses the same
properties. It is fusible at a heat just below that of redness;
and ina close vessel, or a vessel with a very small orifice, it,
is not decomposed or sublimed by a strong red heat ; but if
air, on the contrary, is freely admitted, it is dissipated in’
dense white fumes. It is tsoluble in water. It effervesces’
in nitricacid. It silently dissolves in muriatie acid; from:
which it may be separated by the addition of water, which
precipitates it unaltered ; and it is decomposed by a solution
of potash; or by heating it with the fused hydrated alkali:
when it affords the orange oxide of copper. Its colour,
transparency, and texture appear alone to vary... It is gene-
rally opaque, of a dark brown colour, and of a confused
hackly texture; but I have obtained it by cooling it slewly
after it has been strongly heated, of a light yellow colour,
semitransparent, and crystallized, apparently im. small,
plates, dabei sk :
Cupranea is only very slowly formed by heating cuprane
m chlorine gas. ‘The best mode, that: have.found, of pro-=
euring it, 1s by slowly evaporating to dryness, at a tempera
ture
COMBINATIONS OF OXIMURIATIC ACID AND METALS: 13
ture not much above 400 of Fahrenheit, the deliquescent
muriate of copper. Thus made, it has the same appearance
and the same properties, as when directly formed. It isofa
yellow colour, and pulverulent. Exposed to the atmosphere,
itis converted, by the action and absorption of water, into
the deliquescent muriate; and its colour, during this altera-
tion, changes from yellow first to white, and lastly to oreen.
It is decomposed by heat ; and even in chlorine gas when the
experiment is made on a pretty large quantity, part of the
chlorine is expelled, and assumes the gaseous state, and cu-
prane remains.
I have employed the same methods for ascertaining the Component
proportions of the constituent parts of both these combina- a
tions. Ihave separated the copper by iron, and the chlorine
by means of nitrate of silver.
A solution of 80 grains of cuprane in nitro-muriatic acid, 1st compoun&
precipitated by iron, afforded 51-2 grains of copper, well
washed, and perfectly dried.
_ Asolution of the same quantity of cuprane in nitric acid,
precipitated by nitrate of silver, afforded 117-5 grains of
horn silver, dried till it ceased to suffer any loss of weight by
exposure to a temperature above 500 Fahrenheit,
Since horn silver contains 24°5 per cent of chlorine*, s0
grains of cuprane appear to contain 51:2 grains of copper
and 28°38 of chlorine. And 100 appear to consist of
36 chlorine Component
64 copper | OA
100
‘A solution of 40 grains of cupranea in water, acidulated 2d compound,
with muriatic acid, precipitated by iron afforded 18°8 grains
ef copper.
_ And a solution of 20 grains of cupranea in water, precipi-
tated by nitrate of silver, afforded 43 grains of horn silver.
* This I have ascertained by synthesis; 12 grains of pure silyer Component
dissolved in nitric acid, and precipitated with muriate of ammonia, patts of horn
‘yielded 15-9 grains of fused horn silver. I do uot give the particulars silver,
of the experiment, which was very carefully made; because the result
very nearly agrees with that of Mlaproth, aud of nities chemists.
Hence
14 COMBINATIONS OF OXIMURIATIC ACID AND METALS.
Hence 100 of cupranea, omitting the very slight loss,
appear to consist of
Component 53 chlorine
cout 47 copper
100
are ee The deliquescent muriate, and the natiye muriate of cop~
per of Peru, belong toa class of com pounds apparently dis~
tinct from the preceding combinations of copper and chlos
rine. s
= aeliquese The deliquescent salt is well understood ; and its compo-
i sition may be inferred, independent of its water, from that
of cupranea.
The native muriate is less known, I shall therefore relate
the experiments I have made on this interesting mineral,
the native mu- The specimen I have examined is part of a very fine one,
riae of Peru. resented to Sir Humphry Davy by William Jacob, Esq.
M. P., and deposited in the Museum of the Royal Institu-
tion. It consists of muriate and carbonate of copper, of red
oxide of iron, and of green coloured quartz. The muriate
is partly crystallized; the crystals, from the trials 1 have
made of them, appeared to be pure, and they were, on that
account, made the subject of my experiments,
- Its properties The crystallized muriate dissolves entirely and without
effervescence, in all the acids in which I have tried it, and
the deliquescent muriate of copper is in each instance form~
ed, and a combination of brown oxide of copper with the acid
employed.
Heated slowly in a bent luted glass tube, connected with
mercury, the native muriate affords water and oxigen gas,
and the residue is an agglutinated brownish mass, which dis-
solvesin muriatic acid, and gives a greenish precipitate with _
potash, and is apparently a mixture of brown oxide of cop- }
per and cuprane. When the heat is raised rapidly to red-
ness, the water expelled is impregnated with muriatic acid,
and muriate of copper. I have obtained frem 25 grains of |
the mineral, heated to redness till gas ceased to be produced,
just two cubic inches of oxigen. This expulsion of oxigen
seems to be owing to the action of chlorine on the brown
oxide to form cuprane; and there is, I have ascertained, a
sanilar
COMBINATIONS OF OXIMURIATIC ACID AND METALS. i5
similar production of oxigen when heat is applied to a mix-
ture of the deliquescent muriate and brown oxide of
copper.
From these results, which perfectly ated with those ob- 4 cutmuriate
tained by eminent chemists on the Continent, who have ex- of copper.
amined different specimens of this mineral, it appears to be
a submuriate of copper, differing in a chemical point of
view from the deliquescent salt merely in containing a smal-
ler proportion of acid.
The following experiments v were made with the design of Analysis of it,
ascertaining ine proportions of its constituent parts.
50 grains of the crystals in powder, boiled in a solution of
50 grains of potash, afforded 36:5 grains of brown oxide of
copper heated todull redness.
Aud 20 grains dissolved in nitric acid, and precipitated
by means of nitrate of silver, afforded 12-9 grains of dry horn
silver. j
Hence, considering. the deficiency of weight as indicating
the quantity of combined water, 100 of the native submu-
riate of copper seem to consist of . ‘
73°0 brown oxide 15°8025 clitorine Its component
parts.
16-2 muriatic acid =
10°8 water "47 ~—s+hidrogen
This analysis, allowance being made for the difference of
theory, nearly agrees with that of Klaproth. -
Mr. Proust, I believe, first discovered an artificial com- methods of
pound similar to the native submuriate of copper. He ob- sins oie
tained it in the preparation of the nitre-muriate of copper, artificially.
and also by a partial abstraction of the acid of the deli-
quescent muriate by means of an alkali. I have found that
it may be procured in several other ways. It may be made
_ directly by adding the hydrated blue oxide of copper to a
solution of muriate of copper; and it may be very readily
and economically prepared, by exposing to the atmosphere
slips of copper partially immersed in muriatic acid ; and it is
also produced by the exposure of cuprane to the atmosphere.
Its production in the last instance 1s accompanied with that
of deliquescent muriate ; and the formation of vaih seems to
be owing to the absorption of water and oxigen; for cuprane
I have found, though apparently not in the least acted on
by
10
The results
agree,
.
\ A nalysis.
\
"Fwo com:
pounds of tin
with oximuri-
atic acid.
COMBINATIONS OF OXIMURIATIC ACID AND MEFALSs
by dry oxigen gas, is quickly changed when moistened
with water and confined in a jar of this gas, and there is a
rapid absorption of the oxigene*. ;
{ have not examined all ae specimens obtained. by these
different methods minutely, though sufficiently, 1 conceive,
to ascertain their identity, and their similarity to the native
compound. The colour of all of them is greenish white; like
that of the native, ina finely divided state. When heated,
they all afford water, oxigen gas, and a mixture of cuprane
and brown oxide of copper.
I have analysed only the submuriate precipitated from a
solution of muriate of copper by a weak solution of potash.
Fifty grains of this, well washed and dried, boiled in a
solution of potash, afforded 36:3 grains of dried brown oxide
of copper. ‘
And 20 grains dissolved in nitric acid, and precipitated by
nitrate of silver, afforded 12°75 grains of dried horn silver.
These results differ so little from those obtained with the
native, as fairly to permit the conclusion, that the composition
of the artificial and native subimuriate of copper is the same.
2. On the Combinations of Tin and Chlorine, &c.
Tin, like copper, is capable of combining with two differ-
ent proportions of chlorine. ‘The liquor of Libavius, one of
the combinations, is directly formed by the combustion of
the metal in chlorine gas; and the other, I find, may be
produced by heating together an amalgam of tin and calo=—
mel. Thus akvaitied! it is similar to that which may be
procured by evaporating to dryness the murtate containing
the gray oxide of tin, and fusing the residue in a close vessel.
Both are of a gray colour, and of a resinous lustre and frac-
ture; and both inflame, like tin itself, when heated in
chlorine gas, and are converted into the liquor of Libavius
by the absorption of a fresh portion of chlorine. Hence, as
the liquor of Libavius contains the largest proportion of
chlorine, it may be called stannanea, and the other com-
pound starnane.
* I have been informed, that submuriate of copper is sometimes
found in the neighbourhood of volcanoes, particularly in that. of Vesu-
vius. By means of the above facts, it-is evident that its production.
might be accounted for in such siteations.
) Stannane
COMBINATIONS OF OXIMURIATIC ACID AND METALS. 17
Stannane is fusible at a heat below that of dull redness; it 1st compound
bears this temperature, if air be nearly excluded, without
undergoing any change; but’ when subjected to a heat as
stroag as glass wili bear without being fused, it appears
to be, from the slight fume produced, partially decomposed.
It affords the liquor of Libavius when heated with core
rosive sublimate, nitre, red oxide of mereury, or with the
hyperoximuriate of potash. Ln the last three instances, oxide
of tin is also formed; and with the hyperoximuriate, the
action is so violent, that inflammation is actually produced.
The liquor of Libavius and aurum musivum are formed
when stannaue is heated with sulphur.
Stannane, by the. action of water, appears to be converted
into the insoluble submuriate of tin, and the acidulous
muriate.
The stannanea, or liquor of Libavius that I have examined, 04 compound,
was made by heating together an amalgam of tin and cor- ie of
rosive sublimate, in the proportions commonly recommended,
I have obtained this compound in another way, by treating
the coucentrated solution of the peroxide of tin in muniatic
acid, with strong sulphuric acid; a-gentle heat applied to
this mixture contained in a retort, expels the fuming liquor,
which may be condensed, as usual, in-a cold receiver.
The only new and remarkable property, which I have ob- ftsaction on
served the liquor of Libavius to possess, is its action on oil of oe turpens
turpentine. Iwas led to make trial of it from an idea of ~
sir Humphry Davy, that the combinations of the metals and
chlorine might be soluble in oils. In the first experiment,
when I poured the fuming liquor into the oil, inflammation
immediately took place, with violent ebullition and pro-
duction of dense reddish fumes. 1 have used other speci-
mens of oil of turpentine, expecting a similar inflammation,
but without its occurrence, though there has been in every
‘instance a considerable action. The mixture of the two
beivg made in a retort connected with mercury, no gas was
generated, oxide of tin appeared to be formed, and a viscid
oil was produced, which, like the fat oils, left a permanent
stain. on paper, and had little smell or taste, and which, di=
gested, with alcohol, imparted something which occasioned a
permanent cloudiness on the adguiatdes: of water, and an
Voi. XXXII1—Sepr. 1812. ¢ odour
18 COMBINATIONS OF OXIMURIATIC ACID AND METALS,
odour to me not unlike that of artificial camphor. The
action of the liquor of Libavius on the oil of turpentine is
worthy of farther inquiry. The preceding account of it, I
am aware, is very incomplete; but I trust it will serve to call
the attention of chemists to a subject so curious.
Analysisofthe To discover the proportions of tin, and consequently of
ist compound. chlorine, in stannane and stannanea, I have taken advantage
of the superior affinity of zinc for chlorine, by means of
which the tin is separated in its metallic state.
69°5 grains of stannane, made by heating in a glass tube
with a very small orifice an amalgam of tin with calomel,
were, with the exception of two grains of metallic mercury,
apparently a mere mechanical mixture, entirely dissolved in
dilute muriatic acid. <A slip of clean zinc, immersed in this
solution decanted from the residual mercury, quickly pre-
cipitated the tin in a very beautiful plumose form; and this
precipitate collected on a filter, and well washed, and dried,
and fused into one globule under a cover of tallow in a small
glass tube, weighed 42 grains.
As therefore 67°5 grains of stannane contain 42 grains of
tin, 100 appear to consist of
62°22 tin
37°78 chlorine
100°
Analysis of As stannanea js extremely volatile, it is difficult to weigh
the 2d, it with perfect accuracy. The mode I adopted was to pour
it into a bottle half full of water, the weight of which was
previously ascertained, and to infer the quantity added by
the increase of weight.
81°75 grains of stannanea thus weighed in water, afforded
when decomposed by zinc 34 grains of tin*.
* A little muriatic acid was addcd before the zinc was introduced,
to dissolve the oxide of zinc, which, in other similar experiments, I
observed was rapidly formed, and which, from the large quantity of
bidrogen evolved, appeared to be owing to the decompositiun of water,
chiefly in consequence of the galvanic effect of the contact of the twe
different metals, zine and tine
Hence
COMBINATIONS OF OXIMURIATIC ACID AND METALS. 19
~ Hence 100 of stannanea appear to be composed of
42°1 tin
57°9 chlorine
100°
I am not acquainted with any analytical method for di-
rectly ascertaining the proportion of chlorine in either of the
two preceding combinations. Nitrate of silver, when imme-
diately applied, will not answer the purpose, because the
oxide of silver is partially reduced by the solution of stan-
nane; and an oxide of tin is thrown down in mixture with
the horn silver from the liquor of Libavius.
Mr. Proust, to whom we are indebted for very excellent Sxbmuriate of
investigations of the different combinations of copper and %-
tin, first discovered a subinuriate of tin. He found that a
solution of potash precipitated from the solution of muriate
of tin this compound, and not the pure gray oxide of tin.
[have obtained it by this method, and all its properties, tts properties.
which I have observed, are perfectly agreeable to its sup-
posed composition.
It is decomposed by a red heat. Subjected to distillation
in asmall bent glass tube connected with mercury, no gas
was produced, water containing muriatic acid and muriate of
tin was expelled, and a sublimate like stannane was formed,
and the fixed residue was gray oxide of tin.
It effervesces violently with nitric acid; and strong sul-
phuric acid expels from it muniatic acid fumes.
It dissolves. without effervescence in the muriatic and
acetic, and in the dilute nitric and sulphuric acids; and alj
these acid solutions, as they give a black precipitate with a
solution of corrosive sublimate, appear to contain the tin in
the state of gray oxide.
The complete analysis of this submuriate of tin is difficult. Analysis of it.
The oxide it contains cannot be accurately separated by
potash, nor can nitrate of silver be employed to ascertain the
proportion of muriatic acid.
I have found 50 grains of it, dissolved in muriatic acid, to
afford, when precipitated by zinc, 31 grains of metallic tin.
Now as this submuriate issimilarto the submuriate of copper,
the analogy being imperfect only in the latter containing the
. Ce per-
Two com-
pounds of iron
and eximuri-
atic acid.
2d compound,
ist compound.
Tts solution in
water.
COMBINATIONS OF OXIMURIATIC ACID AND METALS,’
peroxide, and the former the protoxide, it is natural to in-
fer, that the proportion of muriatic acid is similar in both.
But the proportion of muriatic acid in the submuriate of
eopper is apparently half of that which exists in the muriate ;
hence, supposing the composition of the submuriate of tia
to be similar, 100 of it will consist of
70°4 gray oxide
19'0 muriatic acid
10°6 water
100°
Probability alone can be attached to this estimate. I have
not given the calculations by which it was made, as their. date
are liable to objection.
3. On the Combinations of Iron and Chlorine.
As there are two oxides of iron, so there are also two dise
tinct combinations of this metal and chlorine. One may be
directly formed by the combustion of iron wire in chlorine
gas ; it is that volatile compound deseribed by sir Humphry
Davy in his last Bakerian Lecture, which condenses after
sublimation in the form of small brilliant iridescent plates.*
The other, I find, may be procured by heating to redness,
in a glass tube with a very small orifice, the residue which is
obtained by evaporating to dryness the green muriate of iron ;
it is a fixed substance requiring a red heat for its fusion; it
is of a grayish but variegated colour, of a metallic splendour,
and of a lamellar texture. As 14 absorbs chlorine when
heated in this gas, and becomes entirely converted into the
volatile compound; and as the volatile compound may like-
wise be obtained by heating in a glass tube, nearly closed,
the residue from the evaporation of the red muriate, it is evi-
dent, that the fixed compound contains less chlorine than the
volatile, and that the former, consequently, may be called
ferrane, and the latter ferranea.
Ferrane dissolves in water and forms the green muriate of
iron; but the solution of the whole substance is not com-
* Journal, vol, XXIK, p 296,
plete:
COMBINATIONS OF OXIMURIATIC ACID AND METALS. 9}
plete. There is always left a small and variable quantity of
black“oxide, which may be considered, on account of its.va-
riability, in a state of mechanical mixture, rather than of
chemical union with the ferrane.
Ferranea is entirely soluble in water. The solution is Solution of the
2nd.
identical with the red muriate of iron.
The analysis of both these compounds is easily effected Analysis —
by means of nitrate of silver. :
50 grains of ferrane were put into water: the insoluble of the Ist
residue separated from the solution by decantation ; washed, apepqung:
dried, and heated to redness for a minute, previously moiste
ened with oil, weighed 3 grains, and was in the state of the
black oxide, being attracted by the magnet. The solution
entire, precipitated by nitrate of silver, afforded 102°5 grs of
dried horn silver, which indicating 25°1125 grs of chlorine,
the proportion of iron, omitting the 3 grains of oxide,
appears to be 218875. And hence 100 of ferrane seem to
consist of
53°43 chlorine
46°57 iron
100°
.
Ferranea is not easily obtained in considerable quantities, and of the 2d,
I have been obliged in consequence to operate upon small
portions. The subject of analysis was procured by sublime
ation from the residue by evaporation of the red muriate,
20 ers of this, in brilliant scales, were weighed in water. The
solution, precipitated by nitrate of silver, yielded 53 grs of :
dried horn silver, Hence 100 of ferranea appear to consist
of |
. 64°9 chlorine
§5°1 iron
100°
(To be concluded in our-next.J
22
hae
METEOROLOGICAL JOURNAL.
PRESSURE. ‘TEMPERATURE,
1812. |Wind| Max. Min. Med. |Max{M :.{ Med. |Evap.| Rain
_——_ | —-—————— ;
et ——. eee eae
7th Mo,
Jury iS W] 29°70] 29°44 ]29°570] 63;) 52.) 5795, J, —- | 20.1 p..
alVar.| 29°56| 29°40129°480| 65.| 47. | 56°0 | — | +§3
31 N | 30:00] 29°56}29-780] 61 | 42 1515 [—
AlS W) 30°05] 30°01]30°030] 61 | 42 | 51°5 | +45
KIS WI 30°02] 29°96 }29':990| 63 } 51°] 5770 | —
6IN W| 30°27] 30:02]30:145| 67.].50.] 58°5 | —
7) N_|,30:29] 30:27 ]30°280| 72,).51,] O15, | *43 .
8} E_ | 30°33] 30:29}30°310] 71 | 46 | 58.5 @
gIN E] 30°33] 30°29[30°310] 73.} 50 | 61°5
10| N | 30°39] 30°29|30-340| 72 | 51 | 61°5
31] N_ | 30°29] 30°16|30°225| 69 | 54 | 61°5
12|N W| 30°17 | 30°16}30°165| 66 |. 41 | 53°5
13|}N W| 30°19} 30°16}30°175] 64 |: 42 7 58°0
14/Var,| 30°19] 30°17130-180| 64 | 40 ] 55:0 "04
15|Var.| 30°17 | 30°05|30°110}| 69 | 50} 59%5 01
16} E | 30°05} 29-95}30°000| 65 | 55 | 60°0 | — «
17|Var.| 30 14}. 29°95]30-045| 67 | 56 | 61°5 | —
18|S EF} 30°10] 30°00{30-:050| 75 | 56 | 65:5 | -37
195 W| 30°00] 29:74.129°870| 73 | 55 | 64°0 | — | °17
20] W | 29°85} 29-70]29°775| 75 | 50 | 62°35 | — | *34
21} W | 29.96] 29-94}29°950| 65 | 45 | 55°O | °35
22/S W/|' 30:09} 29-96 |29°025| 63 | 42 | 52°56 |'— | 15
23,8 W} 30:09] 29:94 129'015} 65.1 52°]:585 | —
2415 W!] 29:94] 29:78]29°860| 62 |. 58 | 60°0 |. — |. 2619
25|S Wi} 29°79}, 29°78 j29°785| 71 | 57'} 640 1/55) °03) «.
26IN Wj 29°85] 29°79129°820| 68 | 49 | 585 | —
271Var.| 29°66} 29°60 129:630| 61 } 48 | 54°5 | — |1°00
28/S W] 29°66] 29°65 |29°655| 64 + 50 | 57°0 | —
20| W | 29°80] 29°66 |29.730| 63 | 49 | 56:0 | -55| -22
———_— —— | -—— ee | 2 —
30°39 | 29°40) 29°975| 75 | 41 | 58°34 [2°70 [3°04
The observations in each line of the Table apply to a period of twenty-four hours
beginning at 9 A.M. on the day indicated in the first column. A dash denotes that
the resyjt ig included in the next following observation,
NOTES,
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS» 23
NOTES.
Seventh Month. 1. Much wind: very cloudy: rain at
intervals through the day and night. 2. Faira.m. Thun-
der showers with hail, p.m. 3. Cloudy: a few drops of
rain. 4, The wind veered gradually from N. by E. to S.W.
5. Wind moderate, 22. Thunder and hail***,
eT 2.) Be
RESULTS.
. Winds variable.
Barometer: highest observation 30°39 inches; lowest 29°40 inches;
Mean of the period 29°975 inches.
Thermometer: highest observation 75°; lowest 41°;
Mean of the period 53°34°°.
Evaporation (in,21 days, the rest being lost by an accident) 2-70 inches,
Rain 3°04 inches.
PLAISTOW. L. HOWARD.
Eighth Month, 17, 1812.
IV.
Chemical Researches on the Blood, and some other Animal
Fluids. By Wit.1am Tuomas Branng, Esq., F. R.S.
Communicated to the Society for the Improvement of Ani-
mal Chemistry, and by them to the Royal Society*,
I. Introduction.
In the following pages I shall have the honour of laying Analysis of
before this Society an account of some experiments upon ae oe
the blood, which were erjginally undertaken with a view to ka ie iffie
ascertain the nature of its colouring matter. ‘The difficulties
attendant on the analysis of animal substances have rendered
* Philos, Trans. for 1812, p. 90.
some
Tron in the
blood,
Examination
of the chyle
and lymph.
Contents of
the thoracic
duct variable.
:
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS:
some of the results less decisive than I could have wished,
but [ trust, that the general conclusions to which they lead
will be deemed of sufficient importance, to occupy the time
of this body.
The existence of iron in the blood was first noticed by
Menghini*, and its peculiar red colour has been more re-
cently attributed to a combination of that metal with phos-
phoric acid by Messrs, Fourcrey and Vauaquelinf. The
very slight discoloration occasioned by the addition of infu-
sion of galls to a solution of the colouring matter, under
circumstances most favourable to the action of that delicate
test of iron, first led me to doubt the inferences of those
able chemists; and subsequent experiments upon the com-
binations, to which they allude, tended to confirm my suse
picion, and induced me to give up no inconsiderable portion
of the time which has elapsed sinee the last meeting of this
Society, to the present investigation.
An examination of the chyle and of lyntph, in order to
compare their composition with that of the blood, formed an
important part of this inquiry ; especially as those fluids have
not hitherto been submitted to any accurate analysis, on ac-
count of the difficulty of procuring them in sufficient quan-
tities, and in a state of purity. While engaged in assisting
Mr. Home in his physiological researches, several opportu-
nities occurred of collecting the contents of the thoracic duct
under various circumstances, and in different animals ; on
other occasions Mr. Brodie has kindly furnished me with the
materials for experiment.
If. On the Composition of Chyle.
The contents of the thoracic duct are subject to much vae
riation. About four hours after an animal has taken food,
provided digestion has not been interrupted, the fluid in the
duct may be regarded as pure chyle : it is seen entering by
the lacteals in considerable abundance, and is of a uniform
whiteness tiroughout. At longer periods alter a meal, the
* Vincentius Menghinus de Ferrearum Particularum Progressa in
Sanguinem. Comment. Acad. Bonon. T. 2, P. 2, page 475. “
t Systéme des Conn, Chym. Vol 8,p. [Vol. 9, p.152. C.]
; quantity
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS, 95
quantity of chyle begins to diminish, the appearance of the
fluid in the duct is similar to that of milk and water; and
lastly, where the animal has fasted for twenty-four hours or
longer, the thoracic duct contains a transparent fluid, which
is pure lymph.
A. The chyle has the following properties. Properties of
1. When collected without any admixture of blood, it is Mey
an opaque fluid of a perfectly white colour, without smell,
and having a slightly salt taste, age ag a by a degree of
sweetness,
2. The colour of litmus is not affected by it, or that of
paper stained with turmeric; but it slowly changes the blue
colour of infusion of violets to green.
S. Its specific gravity is somewhat greater than that of
water, but less than that of the blood; this, however, is
probably liable to much variation.
4. In about ten minutes after itis removed from the duct, Separates inte
it assumes the appearance of a stiff jelly, which in the course ‘¥° Pa"
of twenty-four hours gradually separates into two parts, pro-
ducing a firm and contracted coagulum, surrounded by a
transparent colourless fluid. ‘These spontaneous changes,
which I have observed in every instance where the chyle was
examined at a proper period after taking food, are very si-
milar to the coagulation of the blood and its subsequent
separation into serum and crassamentum ; they are also re-
tarded and accelerated by similar means.
’ B. 1. The coagulated portion bears a nearer resemblance Properties of
to the caseous part of milk than to the fibrine of theblood. the coagulun.
2. Itis rapidly dissolved by the caustic and subcarbonated Action of
alkalis. With soluti ns of potash and soda it forms pale *!4ls, _
brewn compounds, from which, when recent, a little ammo-
nia is evolved. In liquid ammonia the solution is of a red-
dish hue.
' 3. The action of the acids upon these different compounds acids,
is attended with nearly similar phenomena, a substance be-
ing separated intermediate in its properties between fat and
albumen, Nitric acid added in excess redissolves this pre-
cipitate in the cold, and sulphuric, muriatic, and acetic acids
when boiled upon it for a short time.
4 ney alcohol nor ether exerts any action upon the alcohol and
‘ coagulum ik ae:
and sulphuric
acid,
The solution
im this acid
examined,
Aetion of nitric
acid on the
ecougulum,
€HEMICAL RESEARCHES ON THE ANIMAL FLUIDS.
coagulum of chyle; but of the precipitate from its alkaline
solution they dissolve a small portion, which has the proper-
ties of spermaceti: the remainder is coagulated albumen.
5. Sulphuric acid very readily dissolves this coagulum,
even when diluted with its weight of water; and with the as-
sistance of heat, it is soluble 11 a mixture of one part by |
weight of acid, with four of water ; but when the proportion
of water is. increased to six parts, the dilute acid exerts no
action upon it. I was surprised to find, that the alkalis pro-
duced no precipitation in these sulphuric solutions when
heat had been applied in their formation, and where a small
proportion only of the coagulum had been dissolved ; and
was therefore led to examine more particularly the changes,
which the coagulum had undergone by the action of the
acid.
On evaporating a solution of one drachm of the coagulum
in two ounces of dilute sulphuric acid (con sisting of one part
by weight of acid with three of water) down to one ounce, a
small quantity of carbonaceous matter separated, and the
solution had the following properties.
It was transparent, and of a pale brown colour,
Neither the caustic nor carbonated alkalis produced in it
any precipitation, when added to exact saturation of the acid,
or in excess.
Infusion of galls, and other solutions containing tannin,
rendered the acid solution turbid, and produced a more co-
pious precipitation in that which had been neutralized by
the addition of alkalis.
When evaporated to dryness, carbonaceous matter wes de-
posited, and sulphurous acid evolved, with the other usual
products of these decompositions,
6. On digesting the coagulum in dilute nitric acid, con-
sisting of one part by weight of the acid to fifteen of water,
it was speedily rendered of a deep brown colour, but no
ether apparent change was produced for some weeks; when,
on removing it from the acid at the end of that period, it
had acquired the properties of that modification -of fat,
which is described by Fourcroy under the name of ade-
pocire*.
* Mém. de lAcad. des Sciences, 1789. ss
A mixture
OREMICAL RESEARCHES ON THE ANIMAL FLUIDS. DP
A mixture of one part of nitric acid with three of water
acted more rapidly upon the coagulum of chyle; a pertion
of it was dissolved, and, when the acid was carefully de-
canted from the remainder, it was found to possess the pro~
perties of gelatine. But when heat was applied, or when
a'stronger acid was employed, the action became more vio-
lent, nitrogen and nitric oxide gas were evolved, and a
portion of carbonic acid and of oxalic acid was produced.
7. Muriatic acid in its undiluted state does not dissolve Action of mu.
the’ coagulum of chyle; but when mixed with an equal ainda
quantity of water, ereven more largely diluted, it dissolves
it with facility, forming a straw-coloured solution, which is
rendered turbid when the alkalis are added to exact satura~
tion, but no precipitate falls, nor can any be collected by
filtration. When either acid or alkali is in excess in this
solution, it remains transparent.
8. Acetic acid dissolves a small portion of the coagulum of a“ ‘¢,
_ of chyle, when boiled upon it for some hours. As the so-
lution cools, it depesits white flakes, which have the proper-
ties of coagulated albumen.
9. The action of oxalic acid is nearly similar to that of oxalic, ge.
the acetic, but neither citric, nor tartaric acid, exerts any
action upon this coagulum,
10. The destructive distillation of this substance affords Destructive
water slightly impregnated with carbonate of ammonia, a aisauowe
small quantity of thin fetid oil, and carbonic acid and car-
buretted hidrogen gas.
The coal which remains in the retort is of difficult inciner~ Coal,
ation ; it contains a considerable portion of muriate of soda
and phosphate of lime, and yields very slight traces of iron.
C. 1. The serous part of the chyle becomes slightly tur- Properties of
bid when heated, and deposits flakes of albumen. ei se pass
2. If after the separation of this substance the fluid be ;
evaporated to half its original bulk, at a temperature not
exceeding 200° Fahrenheit ; small crystals separate on cool- Crystals in it,
ing, which, as far as I have been able to ascertain, bear a
strong resemblance to sugar of milk; they require for solu-
tion about four parts of boiling water, and from sixteen to
twenty parts of water of the temperature of 60°. They are
épaninely soluble in boiling alcohol, but again deposited as
the
Destructive
distillation.
Pare lymph,
e
Its. properties,
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS.
the solution cools. At common temperatures alcohol exerts
no action upon them. The taste of their aqueous solution
is extremely sweet. By nitric acid they are converted into
a white powder of very small solubility, and having the pro-,
perties of saccholactic acid, as described by Mr. Scheele*.
The form of the crystals [ could net accurately ascertain
even with the help of considerable magnifiers.. In one in-
stance they appeared oblique six-sided prisms, but their
terminations were indistinct.
Some of the erystals, heated upona piece of platina in the
flame of a spirit lamp, fused, exhaled an odour similar to
that of sugar of milk, and burnt away without leaving the
smallest perceptible residuutn.
3. The destructive distillation of the serous part of chyle
afforded a minute quantity of charcoa!, with traces of phos~
phate of lime, and of muriate of soda and carbonate of soda.
HI. Analysis of Lymph.
The food found in the thoracic duct of animals that have
been kept for twenty-four hours without food is perfectly
transparent and colourless, and seems to differ in no respect
from that which is contained in the lymphatic vessels. It
may therefore be regarded as pure lymph.
It has the following properties.
1. It is miscible in every proportion with water.
2. It produces no change in vegetable colours.
3. It is coagulated neither by heat, sor acids, nor alco-
hol: but is generally rendered slightly turbid by the last
reagent,
4. When evaporated to dryness, the residuum is very small -
in quantity, and slightly affects the colour of violet paper,
changing it to green.
5. By incineration in a platina crucible the residuum is
found to contain a minute portion of muriate of soda; but
I could not discover in it the slightest indications of iron. °
* Chemical Essays, No. XVII,
+ The termlymph has been applied indiscriminately to the tears,
io the matter of encysted dropsy, and to some other animal fluids.—
Vide Aikin’s Dictionary of Chemistry and Mineralogy, Art. Lymph.
6.. In
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS. 99
6.\ In the examination of this fluid, I availed myself with Analysis of it
some advantages of those modes of electrochemical ana~ >Y ¢lectricity-
lysis, which on a former occasion I have described to this
Society*.
When the lymph was submitted to the electrical action of
a battery, consisting of twenty pairs of four inch plates of
copper and zinc, there was an evolution of alkaline matter
at the negative surface, and portions of coagulated albumen
were Separated, As far asthe small quantities on which I
operated enabled me to ascertain, muriatic acid only was
evolved at the positive surface.
IV. Some Remarks on the Analysis of the Serum of Blood.
This fluid has been so frequently and fully examined by Serum of
chemists, that I shall not enter into a detailed account of its ae
composition, but merely state such circumstances respecting
it as relate particularly to the present inquiry, and have not
hitherto been noticed by the experimentalists to whom I have
alluded.
The fluid which oozes from serum that has been coagu- Serosity.
lated by heat, and which, by physiologists, is termed serosity,
is usually regarded as consisting of gelatine, with some
uncombined soda, and minute portions of saline substances,
such as muriate of soda and of potash, and phosphate of
hime and of ammonia. Dr. Bostock regards it as mucust.
From some experiments which I made upon the serum of
blood, on a former occasion, I was induced to regard the
serosity as a compound of albumen with excess of alkali,
and to consider the coagulation of the serum analogous to
that of the white of egg, and of the other varieties of liquid
albumen. !
To ascertain this point, and to discover whether gelatine Examination
exists in the serum, | instituted the following experiments. a
Two fluid ounces of pure serum were heated in a water
‘bath until perfectly coagulated: the coagulum, cut into
pieces, was digested for some hours in four fluid ounces of
* Phil. Trans 1809, p. 373 [Journ. vol, XXVI, p. 14:] .
Ps Fransactions of the Medical and Chirurgical Society of London,
wol, 1, p. 73.
distilled
30
¥t contained
albumen,
bat no gela-
tine,
Action of mu-
rialic acid on
in
Ms
“
CNEMICAL RESEARCHES ON THE ANIMAL FLUIDS.
distilled water, which was afterward separated by means of
a filter.
The clear liquor reddened turmeric paper, and afforded
acopious precipitation on the addition of the infusion of
galls, and when evaporated to half an ounce, ‘it eelatinized |
on cooling, It was rendered very slightly turbid by the ad-
dition of dilute sulphuric and mumiatic acid; but alcohol
produced no effect. |
From the result of these trials, it might have been con=-
cluded, that gelatine was taken up by the water, but as an
alkaline solution of albumen forms an imperfect jelly when
duly concentrated, and as albumen and gelatine are both
precipitated by tannin, I was inclined to put little reliance
on the appearances just described, until I had examined the
solution by the more accurate method of electrical decom
position.
Upon placing it in the Voltaic carat my suspicions were
justified, by the rapid coagulation which took place in con-
tact with the negative wire. I therefore made some other
experiments in order to corroborate this result.
One fluid ounce of pure serum was dissolved in three of
distilled water: the conductors from a battery of thirty pairs
of four inch plates were immersed in this solution at a dist-.
ance of two inches from each other; the electrization was
continued during three hours and a half, the solid albumen
being occasionally removed ; at the end of that period, no
farther coagulation took place, and a mere decomposition of
the water was going on.
Having ascertained in previous researches, that gelatine is
not altered during the electrical decomposition of its solu-
tion carried on as just described, my object in this experi-
ment was, to ascertain whether any gelatine remained after
the complete separation of the albumen had been effected,
1 accordingly examined the water from which the coagulated
albumen had been removed, and found that it was not altered
by infusion of galls, nor did it afford any gelatine when
evaporated to dryness.
Two fluid ounces of dilute muriatic acid were added to
one of serum, The mixture immediately assumed a gela-
tinous appearance ; it was heated, and a more perfect coagu-
lation
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS. 3}
lation of the albumen took place; the liquid part was separ-
ated by a filter. No effect was produced upon it by Voltaic
electricity, nor did infusion of galls occasion any precipi-
tation.
I repeated the first experiment with the addition of twenty Farther test of
4rops of a solution of isinglass to the serum. The liquid com positi-
which now separated, after the albumen had been entirely
coagulated by the action of electricity, was copiously pre-
cipitated by infusion of galls. .
It may be inferred from these experiments, that gelatine It consists of
does not exist in the serum of the blood, and that the se- meee ret ag
rosity consists of albumen in combination with a large pro- much alkali.
portion of alkali, which modifies the action of the reagents
commonly employed, but which is readily separated by elec-
trical decomposition.
To ascertain whether iron exists inthe serum of the blood, Slight traces of
one pint was evaporated to dryness ina crucible, and gradu- im ia it.
ally reduced to a coal, which was incinerated and digested
in muriatic acid, to which a few drops of nitric acid were
added ; some particles of charcoal remained undissolved ;
the solution was saturated with ammonia, which afforded a
copious precipitation of phosphate of lime, accompanied with
slight traces only of oxide of iron.
—-V. Some Experiments upon the Coagulum of Blood.
Mr. Hatchett’s valuable researches on the chemical con- Coaguium of
stitution of the varieties of coagulated albumen have shown, blood.
that this substance varies but little in its properties, whether
obtained from the crassamentum of the blood, or from washed
muscular fibre, or other sources ; but that the proportion of
earthy and saline matter is different in the different varieties*.
It will also be remarked, on referring to the dissertation
which I have just quoted, that the ashes obtained by incine-
rating the coal left after the destructive distillation of albu
men, did not contain apy appreciable proportion of iron.
Assuming the existence of iron in the colouring matter of Inquiry
the blood, I made the following experiments upon the cras- whether the
} colour of blood
samentum of that fluid. be owine to
Two pints of blood were collected in separate vessels, iron.
_* Phil. Trans. 1800, p. 384.
The
32)
s)
Tt appeared
not,
‘Fhis farther
confirmed,
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS.
The one portion was allowed to coagulate spontaneously ; the
other was stirred for half an hour with a piece of wood, so as
to collect the coagulum, but to diffuse the principal part of
the colouring matter through the serum. These two portions
of coagulum were now dried in a water-bath; and equal
weights of each reduced in a platina crucible to the state of
coal, which afterward was incinerated. The ashes were dis
gested in dilute nitromuriatic acid, and the solution satus
rated with liquid ammonia, in order to precipitate the phos
phate of lime, as well as any iron which. might have been
present.
The precipitates were collected, dried, and treated with
dilute acetic acid, by which they were almost entirely dise
solved ; some very minute traces only of red oxide of iron
remaining, the quantity of which was similar in both cases,
and so small as nearly to have escaped observation.
Itis reasonable to infer, that, if the colouring matter of
the blood were constituted by iron in any state of com-
bination, a larger relative proportion of this metal would
have been discoverabie in the former than in the latter coa-
gulum ; but frequent repetitions of these experiments have
shown, that this is not the case, and the following result ap-
pears to complete the evidence on this subject.
The colouring matter of a pint of blood was diffused by
agitation through the serum, from which it was allowed
gradually to subside, the coagulum having been removed :
after twenty-four hours, the clear serum was decanted off,
and the remainder containing the colouring matter, after
having been evaporated to dryness, was incinerated, and the
ashes examined as in former experiments. Bat the traces of
iron were here as indistinct as in the other instances above
mentioned, although a considerable quantity of the colouring
matter had been employed.
The minutiz of analysis I have purposely excluded, as
leading into details which would exceed the proper limits of
this paper, and unnecessary in the present investication; I
shall now merely dwell on the principal results which have
been obtained, and on the general conclusions which fa
afford,
(To be concluded in our next.)
Vy.
ON LUMINOUS METEORS. \ 33
Vv.
On the Nature of falling Stars and the large Meteors, in
Answer to Mr. Joun Farey, Senior. In a Leiter from
Mr. G. J. SINGER.
To W. NICHOLSON, Esq.
SIR,
"Tue appearance of a second communication from your Mr. Farey’s
correspondent, Mr. Farey, on the nature of falling stars*, Pi fel of
: 3 i ; alling stars.
leads me to offer a few observations on that subject, which
would have foliowed his first paper, had not the obviously
hypothetical nature of his suggestion appeared to render
any remark unnecessary,
Mr. Farey notices the electrical nature of these appear-
ances, and their frequent occurrence in “clear frosty nights,”
and the clear intervals ‘of “‘ showery: weathert:” and obs
‘serving that such ‘¢ states of the air are best adapted, by its
** clearness, for seeing the smaller stars and planets,”
supposes ‘ that these phenomena are occasioned by an ale
«© most infinite number of satellitule, or very small moons,
** constantly revolving round the Earth, in all possible die
rections, and appearing only during the very short time
‘¢ that they dip into the upper part of the atmosphere each
‘* time they are in perigee: and that no step seems wanting
** in the degree of this dip into the atmosphere, and their
** consequent brightness, length, and slowness of courses,
“© &c,, between the smallest instantaneous shooting stars,
« and the largest meteors, (such as that of August,
“© 1783.”)
This is the substance of Mr. Farey’s first communica- His assump-
tion; and apparently amounts to an assumption, that the sneer i
phenomena may be explained without electricity ; if i be bie cue
admitted, that clear weather and the absence of twilight, ‘estrsity-
moonlight, &ce, are essential for their observance: and that
n
€
* Journal, vol. XXXII, p. 269.
+ Ib. vol. XXX, p 285.
» Vou. XXXITI.—Sepr. 1812. D planetary
34
Shooting stars
and large me-
teors not the
same.
Facts contra-
dictory to the
conditions as-
sumed by Mr
Farey.
Numereus ob-
servations to
the same pur-
pose by the,
author,
Meteors seen
by him.
let.
ON LUMINOUS METEORS.
planetary bodies may move with immeasurable velocity ; and
appear luminous only when they dip inti our atmosphere.
If we were to accede to all these suppositions, still 1 pre-
sume it would be impossible without manifest absurdity, to
refer two appearances so distinct and dissimilar as znstanta-
neous shooting stars, and large progressive meteors, to the
same cause.
But the supposed conditions for the appearancee of lumi-
nous meteors are not necessary. Mr. Forster has noticed
their occurrence not only in clear weather, but ‘* when cirro-
cumulus and thunder clouds abound.” Mr. Morgan de-
scribed them darting from the vertex of a bright conical
stream of the northern lights ; and Beccaria relates minutely
the occurrence of a very remarkable one, an hour after sun-
set.
For ten years my attention has been much occupied by
these phenomena; I have observed many thousands of them
‘in various situations, and under almost every possible diver
sity of circumstances. Of the smaller meteors (the shooting
stars) I have frequently counted 40 and 50 in an hour, in
the brightest moonlight nights of summer. I have seen
them when no cloud has been ‘apparent, aiid when the at-
mosphere has teemed with clouds; and have occasionally
observed them when the rays of the Sun had searcely ceased
to illumine the atmosphere.
Of the larger progressive meteors [ have seen but three ;
one of these occurred in bright light, at 6 o'clock on a sum-
mer’s evening. Its motion was apparently rectilinear, and
in a borizontal direction from east to west. I had an ope
portunity of comparing the accounts of several other observe
ers, they nearly coincided with my own observation. The
meteor left no visible luminous track, but was followed by
a luminous conical tail nearly three tines the length of its
apparent diameter. It left the field of view to which I was
confined, without dispersion. The second meteor I observ
ed at three o’clock in the morning, in the month of April,
1806. it descended in a curve from a considerable height
in the north to. within an apparently short distance from the
Earth, when it dispersed in. luminous -particles; it left no
impression of a luminous track ; 1tsfortiwas spherical, and
its
ON LUMINOUS METEORS. 35
its size apparently equal to the full moon, which it surpas-
sed considerably in brightness. I had two intelligent cb-
servers with me at the time, and an excellent opportunity
was afforded for this comparison, as the moon was shining,
and the atmosphere unobscured by clouds. The last pro- gq,
gressive meteor [| have bad an opportunity of observing oce
curred on a cloudy, but moonlight night in august 1808,
at one o’clock. It was smaller than either of the preceding,
and of a bright red colour; it described a curve of short
radins; its course was nearly from north to south, appear
ing aud disappearing nearly at the extremities of the same
horizontal line; it dispersed 10 luminous particles ; no track
or train of light was observed,
The peculiarities of smaller meteors are very different. Smaller mete-
They move with inconceivable velocity; their hight is less pitied stan
brilliant; their course usually rectilinear; their appearance ently electricak,
frequent, and attendant on states of the atmosphere known
to be most connected with its electrical changes. Like
lightning they more frequently strike trom one part of the
atmosphere to another, than from the atmosphere to the
Earth ; and like it also, when they appear to strike the Earth,
they leave no evidence of a moon, or planetary body, having
done so.
Large meteors have rarely dispersed over any spot within Difference of
reach of observation, but stony bodies have been found ; but large meteors.
this has not to my knowledge been ever the case with falling
stars, or meteors of a similar nature. From this circum-~
stance, and from the different appearance of their light, the
different velocity with which they move, the frequent ap-=
pearance of the one, and the rare occurrence of the other, I
think the two kinds of meteors are distinctly defined, and
decisively separated.
With regard to the streaks of light sometimes seen in the Occasional
track of shooting stars, 1 am rather inclined to think with steaks of light
2 it es ee __ in the track of
Mr. Farey it may be an optical illusion; but I confess this the smaller
conclusion is in the highest degree doubtful ; though its ac- set ue ee
curacy does not appear to me capable of being easily ascer- Ea yes ae
tained, as various equally probable explanations may be
given of the phenomenon. No light was apparent in the
track of either of the progressive meteors I have observed,
De and
/
36
Nature of
these bodies
not yet clear.
The large me-
teors,
Arguments for
the smaller
being electri-
cal.
Objections to’
the planetary
hy pothesis,
ON LUMINOUS METEORS.
and the occurrence of such an appearance as an atterdant on
rapid motion may be consistently accounted for without re=
ference to optical illusion.
In the present state of our knowledge it is certain no poe
sitive conclusion relative to the nature of meteors 1s warrant-
able; but, in the absence of precise and accurate views,
that explanation should be preferred, which is most exten-
sively applicable to the known peculiarities of their appearance.
The larger progressive meteors are, I think, at present
perfectly mysterious, They are certainly not connected
with any of the obvious phenomena of electricity; and the
chemical character of the stones that have fallen when they
have appeared has been adduced as a proof, that they are
“¢ travellers from another planet.” The uniformity of their
composition appears however to render it probable, that they
are always derived from the same source, and their light is
in all probability the hght of combustion.
Falling stars are evidently a more simple phenomenon.
The arguments in favour of their electrical origin are nu-
merous, as will be apparent from the following summary of
the principal facts.
ist. Their light is similar to the light of the electric spark.
2d. Their motion, like that of electricity, is inconceiv-
ably rapid.
3d. They occur as frequently as other electric changes in
the atmosphere.
4th. Their occurrence is most frequent after such changes
of weather, as are known to influence the electrigal state
of the atmosphere.
5th. Their direction is never constant; they move verti-
cally, horizontally, and af various degrees of inclination, in
all parts of the atmosphere; such is also the case with
lightning.
6th. The appearance of falling stars may be accurately
imitated by electricity; and the circumstances on which
the success of such experiments depend are such as are
likely to occur in the preduction of the natural phenomenon.
If more powerful evidence can be adduced in support of
the planetary hypothesis, it may he intitled to consideration:
in its present state it is mere conjecture; and, as opposed to
facts
GEOLOGY OF MADEIRA. 37
facts, and to analogy, must be considered inadmissabl e ac
cording to the strict principle. of experimental inquiry. A
few of the circumstances opposed to it may be thus stated:
Ist. The number of failing stars, and their frequent, but
not constant appearance.
2d. The rapidity of their motion.
$d. Their transient duration.
Ath. Their occurrence in a cloudy state of the atmosphere.
Sth. Their occurrence when the bright light of the moon
renders many small stars and planets invisible.
6th. Their appearance in the iower as well as higher strata
of the atmosphere.
From the extensive observations I have made many other
particulars might be stated, but I trust what has been ad-
vanced will convince your correspondent of the fallacy of his
hypothesis, and [ cannot but lament he should have stated
with such apparent satisfaction the discontinuance of a ree
ference to these phenomena in Mr. Foster’s valuable meteor
ological observations; agreeing, as I imagine every candid
inquirer will, in the propriety of Mr. Foster’s remark, ‘* that
**it is only by repeated and accurate observations of a
‘* multitude of phenomena, the science of meteorology can
“ be brought to its required perfection.”
“ I remain, sir,
With great regard, yours, &c.
Princes street, Cavendish square, G. J. SINGER.
August the 10th. 1812.
VI.
Sketch of the Geology of Madeira: by the Hon. Henry Grey
Benner. In a letter addressed to G. B. GREENOUGH, ©
Esq., F. R. S. Pres. G. S*.
"Tne following notes were taken during a short stay I Geolegy of
‘made last summer in the island of Madeira. As there ape sie ih little
pears to be but little known of the structure, or of the phe- ;
* Trans. of the Geolog. Soc. vol. I, p. 391.
nomena
38
Its vallies,
Size of the
island,
Hills,
Vallies.
Surface clay.
Extiact vol-
canoes.
GEOLOGY OF MADEIRA.
nomena which the strata in that island exhibit, the following
observations may not perhaps be whol y unacceptable. Tay
may be considered as furnishing directions to others, wiere
to look for some of the most interesting objects; and may
afford to future travellers a small portion of the information,
which my guide, Dr. Shuter, so liberally communitated to
me. That gentleman, having !ong resided in the island, had
repeatedly traversed it, and was thereby able to point out to
me some of the circumstances which were most worthy of
examination, particularly the nature of the various strata that
are exposed to view in the deep and abrupt vallies which in-
tersect the island in all directions. These vallies are no less
picturesque to the eye of the common traveller than they are
deserving of the attention of the geologist. They are 10 ge-
neral narrow and deep, the summits of the hills that form
their boundaries are broken into peaks, rugged and bare,
while their sides are covered with the cedar and other trees
peculiar to southern latitudes, and with a prefuse variety of
shrubs and plants, among which the erica arborea is the most
beautiful, and in the greatest quamiy.
The island of Madeira (though i believe it never has been
surveyed) is said tu be about 50 miles in length, and in its
broadest part abcut 20, but the average breadth does not
exceed 15 miles. :
It consists of a succession of lofty hills rising rapidly from
the sea, particularly on the eastern and northern extremities.
The summits of many of these ranges present the appearance
of what has been called a table laud; yet occasionally the
forms are conical, aud surmounted by a peak, which in some —
Instances [ found to be of columnar basalt. Deep ravines
or vallies descend from the hills or serras to the sea, and in
the holiow of most of them flows a sin II river, which in ge-
neral is rapid and shallo . Th soil of t e island is clay on
the surface, and large masses of it as hard as brick are found
underneath, Though there are not at present any existing
volcanoes in the island, yet the remains of two craters are to
be seen, one on the e stern the other on the western side,
the largest being about a Portuguese league, or four English
miles in circumference. Every thi g around wears ma ‘s
of haying suffered the action of fire, yet I was unable to dis-
cove
GEOLOGY OF MADEIRA. 39
cover any deposit of sulphur, and was told that none had
hitherto beep found in the island.
The varieties of strata, which I shall term generally lava, Varieties of
are not numerous. I myself saw but four, and I was in- Java in strata,
formed there are no more to be met with. Three of them ~
were invariably alternating in the same order. The first or
lowest lava is of a compact species, containing few, if any,
extraneous substances, is of a blue colour, and of a remark-
ably fire grain. Upon that, the second, which isa red earthy
friable lava, rests; sometimes separated by beds of clay
mixed with pumice, and layers of black ash and pumice.
This red lava contains minute pieces of olivine; sometimes
it a-sumes a prismatic form, and in one place was of a mo-
derate degree of hardness: the principal springs of water in
the island issue from this stratum. On the top is the third,
a grayish lava, generally compact, though at times near the ©
surface very cellular, and containing much olivine. This
Java takes principally the prismatic form of basalt. I have
seen itin the most perfect prisms from 30 to 40 feet or more
in height, the surface being covered with scoria, ash, and
pumice. These masses of lava contain more or less of what
I consider to be olivine, occasionally carbonate of lime and
zeolite, which last assumes either a crystallized or globular
form, or is diffused in a thin coating between the different
layers.
The fourth species of lava is of a coarse grain, is used for A distinct strae.
the making of walls, and the commonest and poorest houses '¥™-
are built of it, the blue and gray lavas being used for the
copings, &c. It works easier than the two other kinds above-
mentioned, is more friable and soft, and its colour is a mix~
ture of brown and red. I observed it in a stratum by itself,
and it did not seem to have any connection with the other
three kinds.
These are the principal stratified lavas that the island af- yayiaties not
fords, but inthe beds and rivers, particularly in that which in strata.
flows in the valley of the Corral, several varieties occur in iso=
lated masses, containing olivine and zeolite in greater or less
quantity, and exhibing detached portions of strata, similar
to those that are found in the fossa grande on the side of
Vesuvius,
In
40 GEOLOGY OF MADEIRA.
In the deep and singular valley called the Corral, which I
had an opportunity of examining for several miles, the red
and gray lava alternated five or sx times. The tops of some
Columnar ba- of its barrier hills are formed of columnar basalt; here and
neti there rising to a peak, or broken into what might be termed
a crystallised ridge, or tapering to a point like the granite .
needles in the Mer de Glace. The columnar strata are found
here in all directions. They dip usually to the sea, but oc-
Dykes. casionally are dislocated in the most abrupt manner. Dykes
of lava, rising perpendicularly to the horizon, intersect the
strata at right angles. I saw one 200 or 300 feet in height,
which cut through several of the alternations of the red and :
Valley of the gray lava. This valley of the Corral well merits the most at-
Corral. tentive examination; yet the journey there is one of some
labour, and the walk down the river that flows in its bottom ~
so difficult and toilsome, as almest to deter every one from |
the undertaking. We leit the town of Funchal soon after
day break, aud d.d sot return till between eight and nine at
night, having been, during the whole of that period, ina
state of incessunt exertion on horseback or on foot. The
bed of the valiey itself cannot be descended on mules or on
horseback. The wals is eight or nine miles in length, and
you are compelled to clamber over rocks, as there is not even
a track, or wade, in the bed of the river, which is rapid, and
full of large and pointed stones. Some of the highest. hills
of the island border on this valley. Several of them rise from
the bed of the river in a perpendicular height of 1000 or 1500
feet, judging only by the eye, and are what the French term
taillé & pic. Others are broken into a succession of steep
descents, and are covered with forests of wood and a pro-
fusion of plants. Down many there fall small cataracts of.
water, and some are hollowed into deep recesses, whence
issue from the lava numerous little streams that contribute
to swell the principal river in the valley.
As you arrive on the briuk of the Corral, after a ride of
about 10 miles from Fuochal, you find yourself suddenly on
the edge of a precipice, near to which a sort of traversing
stair-case is cut, with a track winding to the bottom. On
Wall of lavas the right is a wail of lava nearly perpendicular from 400 to
500 re in depth, composed of the two species of the red
and
GEOLOGY OF MADEIRA. 4}
and gray, alternating five or six times, and assuming in its
dislocation the form of a how, both the lavas following in a
regular bend the shape of the curve.
On the left of the stairs by which you are to descend, in- Lava in very
numerable small columns of the gray lava project from the sane
side; they dip N. W. and their form in general is quadran-
gular; but I found several of them in prisms of three, five,
and six sides. They are remarkably small, and as they lie
in this bed, appear almost all to break off from each other at
five or six inches in leagth, and I never found them exceed
this size. They seem to forma dyke that cuts through the
horizontal beds of lava.
At the edge of the descent there is a te aioe or range Basaltic co-
of basaltic columns, rising like a wall, tapering to the top, lumns.
and separating into large quadrangular prisms. We found
no black ashes in the valley of the Corral, though toward Volcanic pro-
‘the bottom there are considerable strata of pumice, great ‘ct
masses of scorie, and cellular lava, and lavain a state of semi~
vitrification, the whole presenting evident marks of an erup-
tion, anterior to that which had formed these various strata
of lava, which are visible from the summit of the hill to the
bed of the river.
The dip of the strata is in general toward the sea. Basal- Dip of the
tic columns shoot from the side of the ordinary strata, St
which are intersected. by various dykes; and one of these in
particular swept across both sides of the valley. There are Breccia.
here also rocks of about 100 feet in height, composed of a
species of breccia. We examined one near the church, at
the extremity of the winding staircase, forming the descent
into the valley, which was composed of large and small
pieces of lava, some of them of many yards in length and
depth, the angles being rounded,and the whole agglutinated
together by a hard black earthy substance, that resisted all
the force we could use to break off a piece of it. There are
other rocks where the red lava forins the base, and these are
soft.
On our road from Funchal to the Corra/ we saw a stratum Nodules of
of large nodules or balls of lava, composed of concentric les fe at
layers similar to the coat of an onion, and lying one above ca
another
42
Coast to the
west of
Funchal.
Cascade to the
east.
GEOLOGY OF MADEIRA.
another; the stratum exposed was 30 or 40 feet in depth,
and appeared to godown to the bottom of the hill.
We also examined the coast to the weetward of the town
of Funchal. From the beach before the town to Illhoo
Castle, and beyond it to the Jand’ called the Punta de la
Cruz, the general character of the coast is as follows: the red
stone is the apparent base upon which rests a bed of gray pris-
matic lava, the stratum being sometimes from 40 to 100 feet in
depth. At times this gray lava rests upon adeep bed of ashes
and pumice, agglutinated together like the peperino and puz-=
zolano in the vicinity of Naples. The scoria at the surface
is remarkably thick, and all the upper parts of the lava ap-
pear to be cellular. The general dip of the lava on the coast
near Funchal is to the north, but near the fort of Illhoo, it
forms with a mass of pumice, that 1s intersected with slight
veins of carbonate of lime and zeolite, a rapid angle or curve
of declination to the east. To the westward of nilap fort the
lava is not found for a little distance, and there is nothing
but deep beds of pumice and the agglutinated mass above-
mentioned. These beds of pumice are of various thickness,
the deepest appearing to be about 4 feet, and alternating
with that stratum which I have called peperino. In dif-
ferent cavities of the pumice bed, there are large deposits of
black ashes. Toward the extremity of the strata the red
stone appears on the surface in a more solid state, and lies
in prismatic masses, the prisms being small, and not exceed-
inga few imches in diameter. Their substance is brittle
and crumbles with ease. This stratum of red lava is of a
short continuance. Passing a small brook, it dips rapidly
to the westward, and in its place, the gray lava is found in a
confused though soinetimes prismatic form, and rises from
the beach while the red lava still runs along the surface to
the height of near 100 feet, the top being covered with a
thiek scoria.
There is also in the vicinity of Funchal, to the eastward
of the town, a fall of water, which, independent of the ro-
mantic beauty of the situation, merits being visited on ac-
count of the exposure of the two strata of lava in their relative
position. The hills are composed wholly of lava, some-
times of a prismatic formation, the red and gray lavas being
visible
GEOLOGY OF MADEIRA. £3
visible on both sides of the valley. Near the head of it, a
short distance from the cascade, the red stratum is at the
bottem, and about 60 feet higher it reappears, and again,
about 200 feet higher, alternating with the gray lava. The
upper red lava dips rapidly to the south, and the strata are
disposed in the following aanuner.
Gray lava.
Lower Red.
The rock, down which the cascade falls, is also intersected
with a red stratuin of about 3 feet wide, that traverses it,
aud dips to the westward, and is broken off by a broad dyke
of gray lava. It appears about 30 feet higher, and dips
again to the westward. The substance of the red rock in
this place is hard, and it breaks into a coluainar form,
being by far the most compact of the red strata I met with
in the island. 1 saw this red lava alsoin the island of Tene-
riffe,\to the eastward of Santa Cruz, as well as in the neigh-
bourhood cf Ovotava.
I have thus endeavoured to give you a slight sketch of The island de»
that which appeared to me most deserving of attention in ta eta
the island of Madeira. The short stay 1 was able to make ;
there prevented a more accurate survey of the island; yet I
saw enough to induce ine to recommend a careful examina-
tion of the strata to those who may have more time than J
had to spare, and more knowledge to estimate the value of
that which was to be seen. To my mind the most interest- Most interest-
ing geological jacts are: Ist, The intersection of the lava by Hae ob-
dykes at right angles with the strata. Qdly, The rapid dips
the strata make, particularly the overiaying of that of the
Brazen Head, to the eastward of Funchal, where the blue,
gray, and red lavas are rolled up in one mass, and lie in a
position as if they had ali slipped together from an upper
stratum. 3dly, ise colum ay frm of t e ‘ava it elf res
posing on, and beng co: ered by, beds -f sco iz, ash s, and
pumice, which affords a sirong argument for the volcanic
origin
,
44 DECOMPOSITION OF SULPHATES BY HEAT.
origin of the columns themselves; and 4thly, The veins of
carbonate of lime and zeolite, which are not found here
in solitary pieces as in the vicinity of Etna and Vesu-
vius, but are amid the lavas and in‘the strata of pumice and
tufa, and are diffused on the lava itself, and occasionally
crystallized in its cavities.
VII.
On the Decomposition of Sulphates by Heat: by Mr. Gay-
Lussac, Member of the Institute*.
Effects of heat THe object of Mr. Gay-Lussac, in the paper of which I
gagged am about to give an abstract, was to make known the effects
commonly of heat on sulphates ; and the experiments he made for this
sy sci purpose led him to results very different from those, that
others had hastily promulgated on no better ground than.
probability. Beside extending our chemical knowledge, this
paper has the advantage of presenting immediate applications
to metallurgy, one of the sciences, to the promotion of which
this Journal is devoted. It 1s in this point of view I shall
present the labours of Mr. Gay-Lussac; and, that their ap-
pleation may be more obvious, I shall take the liberty of
making a little change in the order of his experiments.
Roasting of He observed the phenomena that accompany the roasting
sa of several metallic sulphurets, as well as the results of that
operation: and his experiments farther confirm the opinion,
that the formation of sulphates is unavoidable in the roasting
of sulphuretted ores; and that the separation of the sulphur
is not complete, till these sulphates have been decomposed.
I shall first give his experiments on this subject, and then
proceed to the decomposition of the sulphates.
‘¢ | knew,” says Mr. Gay-Lussac, “ that in several manue
Sulphate of : , :
copper made factories sulphate of copper is made by roasting the sulphu-
by roasting the ret in reverberatory furnaces, At Goslar sulphate of zinc is
meres: prepared by a similar process. I attempted to imitate this
* Journal des Mines, vol. shag p- 325. Taken from the Mém. of
the Society of Arcueil, vol. I.
process
DECOMPOSITION OF SULPHATES BY HEAT. 435
<
process in the small way, and succeeded completely. Res
peating it on sulphuret of iron, and on a mixture of sulphur
and black oxide of manganese, it still afforded me sulphates.
The temperature at which these sulphates were roasted was
a red heat scarcely visible.”
+eeeees “ The formation of sulphuric acid in the roast suiphurie acia
ing of metallic sulphurets is not peculiar to them. It takes formed ia
: 9 » : roasting alka-
place also, and much more decidedly, in the roasting of al- tine as well as
kaline sulpburets. I made some sulphuret of potash, which metallic sut-
remained fluid at a low red heat as long as it was kept from ape
the contact of air: but as soon as air was admitted freely, it
began to thicken; and soon after it became solid, because a
great deal of sulphate was already formed. I removed it
from the fire to powder it, and exposed it anew to the action
of heat. In less than an hour it had lost its sulphurous taste,
and threw down only a white precipitate with acetate of lead.
The sulphuric and muriatic acids extricated nothing from
it. The sulphoret of barytes, treated in the same manner,
likewise afforded me sulphate; but after three hours roast-
ing in a red heat it was still sulphuretted. I examined these They pass di-
two alkaline sulphurets, and several metallic sulphurets, at eae
various periods of roasting, without ever being able to extri- phates,
cate sulphurous acid from them. Consequently they must
pass directly to the state of sulphates.
«© Jt is easy to understand why the alkaline sulphurets Reason of this,
pass immediately to the state of sulphates in roasting ; for
Mr. Berthollet has shown, in the Memoirs of the Academy,
that the sulphite of potash is converted into sulphate at a
red heat, exhibiting an excess of sulphur and of alkali. On
treating sulphite of lead in the same way I obtained a great Oxide of lead
deal of sulphurous acid; which proves, that the oxide of ey more fee-
; 4 5 y than pot.
lead has a much weaker action than potash on sulphune acid. ash on sulphu-
It is probable however, that some sulphate is formed with tc acid.
this oxide also; and if I cannot absolutely affirm this, it is
because what I found in the residuum might proceed from
sulphuric acid contained in my sulphuroys acid.
<¢ All the metallic sulphurets however are not equally adapt- All metallic .
ed to produce sulphates by roasting. A necessary condition for ie ita
the formation of sulphuric acid is its having a base to com- formation of
bine with capable of condensing it sufficiently. [have taken autphuriemeid.
sulphuret
46 DECOMPOSITION OF SULPHATES BY HEAT.
Sulphuret of sulphuret of tin, a metal that does not combine with sulphu«
tiny ric acid but very difficultly; and [ have roasted it in a red
heat for an hour, without any thing but sulphurous acid.
antimony, being produced. In lke manner the sulphurets of antie
bismuth, mony and bismuth, after having been roasted, presented mé
only with traces of sulpburic acid. It may be remembered
too, that, if sulphates of these d'fferent metals be distill-d,
almost all the sulphuric acid passes over, as if it had been
alone. The affinity of the metal for oxigen also has some
and silver. influence. When sulphuret of silver is distilled in a stone
retort with a strong fire, it 1s not decomposed: but if it be
roasted, it decomposes with the greatest facility, sulphurous
acid only is evolved, and the acid is not oxided.
Important cire ‘* Thus, then, an important circumstance, the condensa-
cumstance, tion of the acid, modifies the phenomena presented by the
the conaensa- 2 i 5
tion of the metallic sulphurets iu roasting. When the metals have the
acid. property of combining with sulphuric acid, and causing it to
undergo a certain degree of condensation, sulphates are al-
ways formed. When, on the contrary, they combine but
very difficultly with it, sulphurous acid only is formed,
which flies off, as its great elasticity cannot be overcome by
the affinity of the metallic oxides.”
We will now proceed to the decomposition of the sul-
phates, which is the principal subject of the paper.
Common e+e... * It was supposed,” says Mr. Gay-Lussac, “ that,
aoe on distilling a metallic sulphate, sulphuric acid was obtained, —
sulphates if the oxide were not susceptible of a farther degree of oxi-
dation; or sulphurous acid, if its oxidation might be carried
farther. It was thought too, that all the alkaline and
earthy sulphates with excess of acid were brought back to
the neutral state by the action of caloric, or entirely
decomposed, yielding as the result only sulphuric acid.
erroneous. This theory is not the expression of facts accurately
observed.”......
Effects of «eeeee% The first sulphate subjected to the action of heat
efusee | was that of copper. Water first passed over : but as soon as
copper. the retort began to grow red, white vapours of sulphuric
acid arose, accompanied with a nebulous gas; smelling
strongly of sulphurous acid, and in which a match kindled
several times following, when it had been washed. This gas
therefore
DECOMPOSITION OF SULPHATES BY HEAT. | AT
therefore was a mixture of sulphurous acid and oxigen. As
the distillation proceeded, it appeared to me, that the quan-~
tity of sulphuric acid diminished in regard to the oxigen gas
and sulphurous acid; and consequently that less acid es-
_ eaped decomposition than at the commencement of the pro-
cess. When nothing more was given out, 1 removed the re-
tort from the fire. The oxide had not been fused, and it re=
tained some acid ; which proves, that at a higher temperature
it would have been decomposed completely. ‘The sul-
phurous acid and oxigen gas arose necessarily from the
immediate decomposition of the sulphuric acid. The oxide
of copper dissolved in fact in nitric acid without efferves-
cence: and itis known, that it does not acquire a higher
degree of oxidation in the distillation of its sulphate. The
two gasses were to each other in bulk nearly as two to
a
« Though sulphurie acid has long been prepared by dis- Decomposition
tillation from sulphate of iron, and this has been an object of Spat
continual examination, attention has not been paid to seve-
ral circumstances presented by its decomposition. It was
known, it is true, that the sulphuric acid was always accom-
panied with sulphurous acid :. but as the iron takes a higher
degree of oxidation in this process, it was supposed to give
rise to all the sulphurous acid by decomposing the sulphuric.
Mr. Chaptal was, I believe, the first, who remarked, that a
little oxigen also was obtained. In fact, the sulphate of iron
undergoes the same decomposition by heat as the sulphate
of copper: only the results are modified by this cireum-
stance, as the metal is susceptible of a higher degree of oxi-
dation, the proportion of sulphurous acid to oxigen gas
evolved is greater.”
«© The sulphates of manganese and zinc have exhibited to Sulphates of —
me precisely the same phenomena as the sulphate of cop- ance
per; and therefore I shall not stop to describe them, I
shall only observe, that the first of these salts may easily be
prepared by calcining the black oxide of manganese in a red
heat ; for after this it dissolves readily in sulphuric acid,”
_ © When concentrated sulphuric acid is made to act on Two sulphates
tin, antimony, or bismuth, two compounds are formed. ae
One, which is very soluble, retains a great deal of acid, and
very
48
Action of heat
on them,
Products of
sulphates re-
taining the
acid in weaker
degrees.
Those that
retain it very
forcibly exXa-
mined.
Sulphate of
silver.
Sulphate of
mercury.
DECOMPOSITION OF SULPHATES BY HEAT.
very little oxide: the other, on the contrary, is formed of
much more oxide than acid, and has little solubility.”
«¢ If the first of these componnds be distilled, the sulphu-
ric acid is volatilized as if it were alone: but if the second,
in which the sulphuric acid is more strongly retained, be
subjected to distillation, oxigen gas and sulphurous gas are
evolved.”
«¢ The salts that have hitherto been examined have
yielded different products, according to the strength with
which the sulphuric acid is combined in them. When it is
feebly retained, and has undergone no condensation, it is vo=
latilized by heat as if it were alone, without being decomposed.
If it be retained more forcibly, part only escapes decomposi-
tion, and the other part is converted into oxigen and sul-
phurous acid gasses. The insoluble sulphates, in which
there is no sign of acidity, appearing to retain the acid with
great force, it is essential to know what is the action of heat
on them.”
<< T put some sulphate of silver intoan uncoated glass ree
tort, furnished with a tube for collecting the gas. When it
began to grow red, the sale melted, but was not decomposed.
Having taken it out, I exposed it to a more violent fire ina
stone retort ; and then a great deal of oxigen gas was evolved,
mixed with sulphurous acid, as Mr. Fourcroy announced,
IT did not perceive any dense white fumes as in the preceding
experiments, because very little sulphuric acid was given
out. When the process was finished, I found in the retort
a button of silver completely reduced. Thus the sulphate
of silver is decomposed by heat like the other sulphates, but
it gives out more oxigen than they ; on the one hand, in con-
sequence of the reduction of the metal, on the other, because
it yields very little sulphuric acid.”
‘© T afterward prepared some sulphate of mercury, by
precipitating nitrate of mercury little oxided with sulphate
of soda. The precipitate, washed and dried, was exposed
to heat in an uncoated glass retort. Scarcely had this begun
to grow red, when the salt entered into fusion, and it was
soon decomposed. Very little sulphuric acid passed over;
and mercury sublimed, with a little sulphate. The other
products were sulphurous acid and oxigen gasses mixed in
the
DECOMPOSITION OF SULPHATES BY HEAT. 49
the proportion of 51:5 to 48°5. Though oxide of mercury
requires a higher temperature for its reduction than the ox-
ide of silver, the sulphate of silver is not so readily decom-
posed as that of mercury. This difference may arise in part,
no doubt, froin the difference in the affinities of the metals
for sulphuric acid; but it must depend likewise on the great
volatility of the mercury. !n general it appears to me, that
the affinity, the more or less easy reducibleness of the me-
tals, and their volatility, must be considered as so many
causes, capable of modifying the action of caloric on their
sulphates.”
“<< From my first experiment with sulphate of lead, not Sulphate of
having employed a temperature sufficiently high, I con- ae.
cluded, that it was not decomposable by heat. But on
having recourse toa reverberatory furnace surmounted with
a chimney, | obtained its decomposition, and collected a
great deal of oxigen gas and sulphurous acid. I did not
perceive any lead reduced, or any very sensible quantity of
sulphuric acid. It is very possible, that the separation of
_ the acid was determined by the action of the stone retort,
for it was coated internally with vitreous glaze*. Be this as
7t nay, it is evident, that the sulphate of lead, which is inso-
luble and without excess of acid, and the decomposition of
which cannot be promoted either by the easy reduction of
the oxide, or by the volatility of the metal, is much more
difficultly decomposed by fire than the acid and soluble
sulphates. We may conclude therefore, that the insoluble
~~ sulphates resist the action of caloric more than those that are
soluble, and that they give out much less sulphuric acid. But’
to render this conclusion still more general, we must take into
consideration the more or less easy reduction of the metals,
and their volatility.”
- “ Tt may have been observed, that the soluble sulphates Difference be
yielded more sulphuric acid, than those that are insoluble. aaa
When the former have lost a part of their acid, their solu-
- blity is diminished, the acid remaining is held with more
* This suspicion of the author appears to me well founded. The
great affinity of the oxide of lead for earths, and particularly for silex,
must facilitate the decomposition of the sulphate, if it he not its
sole cause.
Vou. XXXIII.—SeEpr. 1912. E force
50
Two portions
DECOMPOSITION OF SULPHATES BY HEAT.
force, aud then they must approach nearer the second. We
of acid in me- can conceive two portions of acid in metallic sulphates: one,
‘allic sulphates,
Alkaline and
earthy sul-
phates.
Roasting of
sulphurets.
Another mode
ef decompos-
ing sulphates
by heat:
which is feebly retained, escapes without undergoing de-
composition; the other, which is retained more strongly,
supports a more elevated temperature, and is decomposed
into sulphurous acid and oxigen gas. ‘These two portions of
acid, which we may conceive to exist in sulphates, are not
the same in all: and it appears, all other circumstances being
equal, that, the more soluble a salt is, and the greater its
excess of acid, the more sulphuric acid is obtained in its
distillation. Hence it is, that sulphuric acid may be pre-
pared, as is done in Germany, by distilling su}phate of iron
or of zinc. The insoluble sulphates would not be any way
adapted to this purpose.”
Mr. Gay-Lussac has extended his researches to the al-
kaline and earthy sulphates; and he has found, that the
salts with excess of acid comport themselves altogether ag
the metallic sulphates; that is to say, they give out sul-
phuric acid, sulphurous acid, and oxigen. ‘Those that do
not admit an excess of acid do not yield, even if sulphuric
acid be added to them, either sulphurous acid or oxigen
gas; and nothing is obtained in distilling them but the acid, .
that exceeded what was requisite for their neutralization,
Such are the sulphates of barytes, lime, &e.
The author, applying. all these facts to the roasting of
sulphates, coneludes...,.* that, when the roasting is per-
formed at a temperature equal to that at which the sul-
phates are decomposed, and still more when at a higher
temperature, no sulphuric acid will be obtained, and all the
sulphur will be given out in the state of sulphurous acid.’’.
‘«« Beside this mode of decomposing sulphates by heat,
there is another, which is more convenient, as it does not
require so high a temperature. It is, that employed by Mr.
the addition of Gueniveau to. decompose the sulphate of lead, distilling it
sulphuret,
with the sulphuret of the same metal*, I satisfied myself,
that by treating the sulphates of iron and copper in like
manner with the sulphurets of the respective metals sul-
phurous acid only was obtained: which proves, Ist, that in
this way we may separate the sulphur from metallic suls
* See Journal, vol. XVIII, p. 203, 204.
a phurets |
DECOMPOSITION OF SULPHATES BY HEAT. 5]
phurets and sulphates; 2d, that to effect this separation does
not require so high a temperature as is necessary to decom-
_ pose the sulphates.”
« Lastly in distilling a metallic oxide and its sulphuret, a Metallic oxide
great deal of dal/burous acid is obtained, and a little sul- distilled with
phate: but, if the temperature be sufficiently high, nothing sea act
remains but sulphuret, or merely oxide, according to the
proportions employed.”
** Now we are acquainted with the various circumstances, Theory of the
that may present themselves in the roasting of a sulphuret, ee of sul-
it is easy to give the theory of it. To roast a sulphuret is, as tea ay
the ultimate result, to separate the sulphur by the the simul-
taneous action of air and heat. The products obtained
vary in general according to the temperature, and to the
sulphuret roasted. At an ordinary red heat these sulphu-
rets, the metal of which combines but difficultly with sul-
phuric acid, yield scarce any thing except sulphurous acid.
Those, on the contrary, that condense it strongly, yield also,
it is true, sulphurous acid ; but at the same time sulphuric
acid is produced, which remains combined with the oxides,
At a very high temperature, superior to what would be ne-
cessary to decompose the sulphates, all sulphurets yield
only sulphurous acid. When once sulphate is formed, it
niay be decomposed by a more powerful action of heat; or
still better by those parts of the sulphuret, that have not yet
undergone any change. In fine, when other portions have
Jost their sulphur, and are oxided, they are capable of
taking the sulphur from those that still retain it, and con-
verting it into sulphurous acid.”
The author has availed himself of the facility, with which, Examination
in the decomposition of sulphates, the sulphuric acid per gs
yields its two component parts, sulphurous acid and oxigen, phutic and.
to ascertain the composition of this acid. He has found, S¥phureus
that 100 parts by measure of sulphurous acid gas take 47°79 “eae
of oxigen gas to form sulphuricacid ; and, admitting the
proportions given by Klaproth for the sulphate of barytes,
he thence deduces the composition of sulphurous acid, which
is 100 sulphur to 91°68 of oxigen.
Mr, Gay-Lussac afterward describes the ingenious experi- Sulphuric
ment, in which he decomposed pure sulphuric acid simply 2*!4 ¢ecomm
E 2 by
fi
52
DECOMPOSITION OF SULPHATES BY HEAT.
posed by heat by heat, by passing it through an incandescent porcelaiw
alone,
Different ef
fects of heat
on sulphates.
Eifects of the
attraction of
the base for
the acid.
<seneral de-
ductions.
Decom posi-
tube, thus obtaining oxigen and sulphurous acid gas.
This experiment explains the decomposition of sulphates.
«© All the neutral or acid sulphates, that lose their acid at
a temperature below that required for decomposing sul-
phuric acid, will decompose without giving out oxigen or
sulphurous acid. Those, on the contrary, that retain all
their acid so strongly as to resist a heat equal or superior to
that which decomposes sulphuric acid, will give out only
oxigen gas and sulphurous acid. Lastly, as a compound
does not equally retain every portion of its elements, there
are sulphates, the decomposition of which will partake of
the two preceding, and which will give out sulphuric acid,
oxigen gas, and sulphurous acid.”
Thus then, setting aside the particular influence of a
given base, we should consider the affinity, that unites the
sulphuric acid to the base with which it forms asulphate, as
a force that enables it to support without being volatilized a
heat sufficient to decompose it ; while, if it had been free,
it would have withdrawn itself from the action of the heat,
long before it experienced the degree necessary for this de-
composition. But this force of affinity is likewise an addi-
tional obstacle to be overcome by the action of heat: and
this obstacle is very considerable, when the base undergoes
no alteration by heat, as the oxide in the sulphate of lead,
and the fixed alkalis in their sulphates,
The paper contains many other very delicate researches of
considerable importance to the chemical theory of several
phenomena, but I shall here finish my abstract with the
following
** Conclusion.
‘ist. All the metallic sulphates are decomposable by
tion of the mce the action of heat, affording results that depend on the afs
tallic sul.
phates,
finity of the metals for sulphuric acid. The sulphates in
which the acid is but little condensed yield only sulphuric
acid by distillation. ‘Those that retain it more strongly, and
-are insoluble, give out sulphurous acid and oxigen gas.
Lastly, those that have properties common to both the
preceding
DECOMPOSITION OF SULPHATES BY HEAT. 53
preceding, and which are acid and insoluble, give out sul-
phuric acid, oxigen gas, and sulphurous acid.
2d. In the roasting of metallic sulpburets, the products metallic sul-
vary according to the temperature, and according to the phurets,
sulphuret. Ata very high temperature, sulphurous acid is
given out in quantities so much the greater in proportion as
the oxide is capable of condensing it more strongly ; and
when it has but a very weak affinity for it, no sulphurous
acid is formed.
<‘ 3d. All the earthy sulphates, which are naturally acid, earthy sul-
are decomposable by fire, giving out sulphuric acid, oxigen Phates,
gas, and sulphurous acid.
_ Ath. The neutral alkaline sulphates are not decomposa- and alkaline
ble by fire, that of ammonia excepted: but when they are eet
capable of forming crystallizable salts with excess of acid,
condensing it, and diminishing its volatility, part of this
excess of acid is changed into oxigen gas and sulphurous
acid.
«© 5th, Sulphates treated in the fire with phosphoric or Action of
boracic acid yield sulphuric acid, oxigen gas, and sulphurous afb
acid. acid.
“6th. Sulphuric acid is composed of 100 parts sulphur- Composition
. ous gas, and 47°79 oxigen gas, by measure. of sulphuric
«7th. 100 parts of sulphur by weight require 50°61 of _ be ye
exigen, to convert them into sulphurous acid, and 85°70 to ;
_ form sulphuric acid.
« 8th. Sulphuric acid is decomposable by heat alone into Sulphuric |
oxigen gas and sulphurous acid gas. acid decom-
in A great ere pA a ae is not favourable atl apo
Manufacture
to the production of sulphuric acid; on the contrary, it is of sulphuric
detrimental to it. The instant of the combustion of sul-
phur, sulphurous gas only is obtained, whether it take place
in the open air or in oxigen gas; and the sulphuric acid
obtained in leadenchambers ‘must be the result of the action
of nitrous gas and of the air on the sulphurous acid, as well
as of the action the last mentioned gas exerts on oxigen
by means of water, :
a4
USE OF METEOROLOGICAL OBSERVATIONS TO NAVIGATORS. .
VIL.
Remarks on some useful Applications of Meteorological Ob-
servations to Nautical Prophylactics: by F. Peron, Natu-
ralist of the Voyage of Discovery to the Austrul Lands,
- Correspondent of the Imperial Institute, &c.*
Meteorological Mlereorotocicat instruments, it is true, are but
observations
on land
and at sea,
Observations
connected with
the health of
seamen.
modern acquisitions to science; yet observations with them
have been pursued so steadily, and in so many different cli-
mates, that we have reason to be equally astonished at the
imperfection of their theory, and of the few useful applica-
tions they furnish, Perhaps the chief reason of this is to be
found in the nature of the theatre on which these experi-
ments have been made almost exclusively to the present
day. In fact, how many joint causes concur, in the midst of
our continents, to complicate results essentially so different
and so delicate! The observer on the ocean, on the contrary,
left to the exclusive influence of the air and water, may give
greater precision and developement to his experiments, and
deduce conclusions more exact, and more general in their
application. It is not my intention here to enter into what
I had myself an opportunity of doing in this way amid so
many seas, repeating my observations daily at six o'clock
morning and evening, at noon, and at midnight; but to con-
fine myself to a few experiments, which appear to me more
immediately connected with the health of mariners.
In this class I conceive may be placed a series of tables of
the variation of the barometer, hygrometer, and thermoe
meter, and of the temperature of the sea at its surface, taken
at every hundred leagues for 95 degrees of latitude; an une.
dertaking that appears to me as new, as it is capable of
becoming at a future period of importance in preserving the
health of seamen. By multiplying tables of this kind, con-
structed with as much care as [ employed in it, we should
soon have a kind of meteorological hydrography, equally
indispensable to the natural philosopher and the physician.
The latitude and longitude of a part of the sea being given,
* Journ. de Phys, voi. LKVIH, p. 29.
we
USE OF METEOROLOGICAL OBSERVATIONS TO NAVIGATORS. 55
we might find by these tables the general state of the at-
mosphere and water pertaining tu it ; and thus ascertain its
influence on the mariners who traverse it, and the animals
that people it.
In ‘my meteorological labours, however, I had in view an
object still more essential, and more immediately useful to
seamen. ‘Theory and experience, in fact, seem to unite to Chief cause of
prove, that the chief, if not the exclusive cause of scurvy is ScUrvy-
moisture, whether combined with heat, or with cold. This
opinion, which Mr. Kerauden has particularly unfolded in
his excellent dissertation on this subject, and which my own
disasters confirmed, led me to consider it asa duty, to direct
.my inquiries to this subject; and to pursue them with the
more care, as I had the advantage of being the first to tra-
verse the seas with an hygrometical instrument capable of
being compared with others, that of de Saussure, executed
by Richer. Besides, Mr. Hallé, to whose instructions and
advice I am so much indebted, recommended observations
of this kind to me at my departure; and the desire of tes-
tifying my gratitude to him, at least by my zeal, was a
powerful motive with me to undertake them.
Independant of my other meteorological researches, there= 7... who's
fore, I imposed on myself the task of making particular observations.
experiments on the comparative state of different parts of
our vessel. Every ten days, at noon and at midnight, I
‘went from the poop beneath the. quarter deck and fore-
castle*, thence to the gunroom, and lastly to the hold, where
I caused myself to be shut up for half an hour, to obtain
results more exact, and more accurately comparable. The
captain, who had requested me to communicate to him the
results, and transcribed them. into his journal, always
afforded me, as I must candidly confess, every possible con-
venience for this purpose; and in this respect, at least, he
was pleased to second my endeavours.
My observations toward the close of october 1800 showed Information
me, that the matter of the vomitings of seyeral persons at- derived from
tacked with seasickness, and too much crowded in the gun- ie
room, had altered the air in a dangerous manner by its
~ * Sous le gail’ards, in the original ; though, from the table, I sup-
pose the author means the between-decks. C. ;
decomposition,
Another in-
stance.
A thid.
USE, OF METEOROLOGICAL OBSERVATIONS TO NAVIGATORS.
decomposition. The tempestuous weather we had experi-’
enced for several days not having allowed us to open the
ports, this occasioned other inconveniencies, not less serious
than those from the cause just mentioned. The therme-
meter, which without was scarcely so high as 8° [46-4° F.],
in the gunroom was at 15° [59° F.]; and the hygrometer
rose from 78° to 96°. Lastly, a considerable portion of sul
phuretted hidrogen gas evinced its presence, not merely by
its peculiar smell, but by the yellow hue almost every article
of silver in the place contracted. On the report I made to
the captaia, the taking down all the hammocks was strictly
euforced, the decks were carefully swept, fumigations were
repeatedly made, the ports were directed to be opened, a
windsail was employed, and in a few days the former salu-
lubrity of the gunroom was restored,
In my report of the 21st of november I again apprised
the captain, that the excessive heat I observed during the
night in the gunroom indicated, that too many persons slept
in it; and as this dampand hot temperature could not fail to
be prejudicial to all, it was indispensably necessary to remove
someof them. The captain reduced the number from twenty=
four to fifteen or sixteen, and the results I obtained the fole
lowing night confirmed the justice of my observations.
On the 11th of december, on going into the hold, I per ©
ceived a sour, nauseous, and extremely disagreeable smell ;
and my candle burned with difficulty. I soon learned, that
a cask of wine had been leaking for some days; so that I had
no difficulty in accounting for the smell, and for the great
proportion of carbonic acid gas, I hastened to acquaint the
captain with this; and recommended pumping the ship dry,
throwing fresh water into the well, and pumping it out ree
Heatediy. Orders were immediately given for this purpose,
and the ship was once more rendered sweet by my advice,
My experiments at the close of december afforded me a
triumph peculiarly flattering, as they served evidently to
prove the importance of meteorological observations on board
ships. The storeroom of the captain and principal officers
was filled with all sorts of provision put on board in Europe ;
fruit dry and preserved, adqubages in large quantity, . fats,
oils, &e. On going into it with my instruments, I. was
equally
USE OF METEOROLOGICAL OBSERVATIONS TO NAVIGATORS. 57
equally surprised and grieved at the results they offered me:
and I eave an account of them to the captain in the follow-
ing words. “pte
«* A noisome smell, and excessive heat and moisture, con- Report to the
spire to render the storeroom unwholesome. On attempting captain. j
to make my usual experiments there, I found myselfso ill _
and faint, that I could not finish them. My thermometer
however had already risen to 27° [80°6° F.], and the hygro-
meter was beyond the point of saturation. The flame of
the candle was feeble and pale, indicating the presence of
a great quantity of gas unfit for respiration. It is true no
one lives in the storeroom: but is there not reason to fear,
that such of the men as are obliged to work there will soon
feel its fatal effects? It appears to me, therefore, indispen-
sably necessary, to empty this place for a few days, and to
endeavour by fumigations, sprinkling with cold water, vent-
ilating, and repeated sweeping, to renew the air, and remove
its humidity. This precaution is as necessary for preserving
the provision, as for the health of the men: for there can be
no doubt, that many articles are already spoiling, and
others will soon be so, from the high temperature and ex-
treme moisture combined, At any rate, if the nature of the
service will not allow these means to be employed, it is to be
wished, 1, that the men were forbidden to go alone into the
storeroom ; not only to prevent suffocation, of which there are
but too many instances in‘similar cases; but to obviate the
more fatal etfects that might follow, should such an accident
take place, from the person’s being left, or from the candle:
2, that the men should have their allowance of wine in-
creased one fourth; for it is to be feared, that, coming out
of the storeroom in a profuse perspiration, some accident
might happen from their drinking a large quantity of water
to quench the thirst produced; an effect I could not avoid
myself, notwithstanding the short time I staid, and my re-
maining almost perfectly still.”
The captain, alarmed at this report, immediately seit for Neglected
the officer, under whose care it was, and communicated it '°™ see
to him. He asserted, that it was altogether erroneous, that othcen, ver
‘the observations were of no consequence, that the stores
were in good condition, &c, Accordingly nothing was done: :
but
/
$8 USE OF METEOROLOGICAL ORSERVATIONS TO NAVIGATORS,
Consequence. but ina few days after one of the strongest of the men, being
employed in this storeroom, fainted away, and was with dif-
ficulty recovered. This accident, which I had so clearly
foreseen, determined the captain. He ordered the store-
room to be cleared, and the stores to be examined. More
than half the adaubages were rotten: all the dried fruits had
fermented; the oils and fats had run from all the vessels, and
some of them were obliged to be thrown into the sea. It was
found necessary to clean the storeroom in the manner I at
first proposed, and I set the greater value on my ebservations.
Putrefsetionof On the Ist of january, 1801, I found in the gunroom a
PRAIIEEs large chest of potatoes, belonging to the gunner, which,
being stowed under the tiller, had rotted there, and diffused
a noisome smell throughout that close place. With this I
acquainted the captain, who ordered them to be thrown into
the sea, and the gunroom to be cleaned and fumigated.
and ef carrots. On the 10th of the saine month I found a cask of carrots,
belonging to the midshipmen’s mess, which had been stowed
tu the gunroom, and, having been forgotten, had rotted there.
OLE cheese. On the 20th I procured a large chest of old cheese, that
had just been opened in the gunroom, to be removed toa
place that was more roomy, and better ventilated.
$ulphuretted The same day the extreme heat and moisture in the hold,
hidrogen gas i2 and the suffocating smell of sulphuretted hidrogen prevail-
the hold,
ing there, rendered it incumbent on me to acquaint the
captain with it; and to request him, to order the water to
be pumped out, and fresh to be thrown in. This was ime
mediately done.
ané the gun. Jt has been seen, that sulphuretted hidrogen. gas was
a neate several times produced in abundance in the gunroom, and
still more in the held: perbaps it may be necessary, to point
out its origin.
Hrs oxigin, Pallas nicely the seams of a shied may be caulked, it is
impossible but more or less water will penetrate them, par-
ticularly in hard gales, when the seams open, as the sailors
say, from the shock of the waves. Hence independent of
accidents, there is a permanent cause of more or less water
accumulating at the bottom ofthe ship. In the same place
are stowed those pigs of iron, that are employed as ballast.
From the simple action of water op this metal, an evolution
of
USE OF METEOROLOGICAL OBSERVATIONS TO NAVIGATOR,
of hidrogen gas must take place in the hold; but this action
is increased in consequence of the salts with which the water
is impregnated, and the high temperature generally prevail-
ing in the hold: and this hidrogen gas receives from various
vegetable or animal substances 1n a state of decomposition,
in the place where it is evolved, those noxious qualities,
and that sulphuretted smell, of which I have several times
spoken.
59
It is easy however, in a ship in good condition, to prevent, Remedy fox
if not the formation of this gas, at least its injurious effects. >
This is to be accomplished chiefly by frequently pumping
the ship out dry, and then throwing in a large quantity of
water, both to wash out and carry off all the substances ina
state of decomposition, and to cool the hold. But in ships
where these little attentions are neglected, the black oxide
of iron, which is formed in abundance by the decomposition
of the ballast, mixing with the remains of vegetable and even
animal substances in a state of fermentation, produces a kind
of stinking black mud, the exhalations of which have free
quently produced fatal diseases on board ships.
Hence it is easy to perceive, how much this part of the Necessity of
ship should be an object of attention to the officers and sure
geons. From it arise most of those noxious gasses, and of-
fensive smells, that render living on shipvoard so unpleasant.
The thermometer and hygrometer constantly afforded me
valuable data respecting the state of this place with regard
to its salubrity ; the evolution of gas, and consequently the
decomposition of water and of the animal or vegetable sube
stances, being pretty generally in the ratio of the tempera-
ture and moisture combined: their use therefore cannot be
too sedulously recommended. The same may be said of the
preventive means I have mentioned, to which must be added
above all the apparatus for oximuriatic gas; as here in pars
ticular it may be employed with the greatest success, and
without any inconvenience.
attention t@
the hold.
The observations I have just mentioned were uearly the The author
last of the kind I could make. Notwithstanding the request obliged to
of the captain himself, I was obliged to sacrifice them to pri-
vate considerations, which it would be useless to mention
here. So true it is, that to have both the means and the de-
sire
cease his obe«
servations,
60 DSE OF METEOROLOGICAL OBSERVATIONS TO NAVIGATORS,
rkouch their Sire of doing good is not always sufficient. I consoled my-
xivantages had self however by reflecting, that I had acquired a certainty of
as pore the advavtages of meteorological observations on board ships;
; and I am still firmly persuaded, that the continuation of si-
milar labours, and the particular inspection to which they
would have led, would have been of great service during the
rest of the voyage; and though ‘they would uot have pre-
vented the dreadful scurvy, that made such ravages among
our crew, they would perhaps have checked its progress.
The little good I was able to aceomplish, while it preves the
utility of such experiments, will no doubt stamp a due value
on the counsels of our naval officers of health, and may thus
contribute to the improvement of nautical medicine, too
little acquainted hitherto with the assistance it may derive
from that application of natural philosophy to the healing
art, which Mr, Hallé has so successfully pointed out.
Advantages of | What for instance can be more easy, and at the same time
eet ne ce more necessary, than to place in the care of the surgeon of
beni She Bs every ship a good marine baremeter, a few thermometers,
buard.all ships. and a couple of hygrometers 2? What series of valuable ob-
servations on the constitution of all the climates on the globe,
and what important materials for nautical medicine and the
science of natural philosophy, would thus be acquired at a
trifling expense ! How advantageous also would these instru-
ments be to marinere themselves! I do not speak merely
with respect toa more accurate judgment of changes in the
atmosphere, which the barometer and hygrometer would fre-
quently furnish, and which. established the reputation of
these instruments with the officers of our expedition; but
with regard to their health, and its preservation. Beside
what I have already said, how often, for instance, at an an
chorage, or when tents were pitched ashore, the changes of
the weather having been shown to be dangerous by our me-
teorological instruments, might the crew have been preserved
from their effects at a trifling expense, and without incon-
Setting up veaience!_ Thus at the bead of the Bay of Seals, where I
teats ashore. observed variations of 20° [36° F.] of temperature and 33° of
humidity within the 24 hours, those of the crew of the Natu<
raliste who slept on shore being almost all attacked with a.
Violent diarrhoea, need we seek any ather cause for it than
the
USE OF METEOROLOGICAL GEBSERVATIONS TO NAVIGATORS. 61
the daily and alarming vicissitudes of the weather? And when
the results of our. meteorological observations had pointed
out the true etiology of this kind of epidemic, would they not
have led a sagacious observer to the means, equally simple
and efficacious, which the natives of this coast, afflicted no
doubt by such fatal changes, have contrived to diffuse around
them, to obviate their dangerous effects ? means which were
probably the fruit of too long experience, and too long mis-
fortunes to these rude people*.
By the assistance of the same instruments how often should Ordering up
we be led to act with more caution in regard to exposing hammocks.
the seamen to the weather, and the daily practice of ordering
up all the hammocks! How often might we not intreduce Regulations of
with equal advantage and facility some salutary variations —<
either in the distribution of the provision, or in the succession
of the various aliments, with which a ship is furnished! On
seing daily the thermometer sink instantaneously several de- Washing
grees, and the hygremeter indicate 8° or 10° of additional Aras
moisture, precisely when, by order of the captain, the deck,
forecastle, quarterdeck, and great cabin, had just been slui-
_ eed with sea water for the purpose of cleaning them, what
commander, less opinionative than ours, but would have been
eager to puta stop to such a fatal practice ? what officer but
would haye preferred simple dry scraping to those monstrous
ablutions with salt water, which daily filled the interior of
the ship with a damp and cold atmosphere, and in my opinion
contributed not a liitle to the rise of that terrible epidemic
scurvy, which destroyed our crew on the coasts of Napoleon
Laud, and Van Diemen’s Land?
| They who are unacquainted with the minutic of long Attention te
voyages may think most of these precautions useless : but if little circum~
: : stances im-~
‘they reflect on the importance attached to them by the most portant.
_eelebrated navigators, and particularly by the most successful,
they will be convinced, that an attention to a multitude of
httle things, apparently indifferent, especially if considered
singly, form the essential basis of that science of preserving
the health of seamen, sanctioned by the valuable success of
* For an explanation of this passage, see chap. XXX of the Nar-
«ative of our Voyage, where I have described the singular habitations
gf the people of Endracht’s Land. :
3 Bougainville,
62 USE OF METEOROLOGICAL OBSERVATIONS TO NAVIGATORS:
Bougainville, Cook, Vancouver, and Marchand. In the
ship of the last of these in particular the aft of preventive
medicine displayed in a striking manner what may be ex-
,pected from these little attentions. Mr. de Fleurieu, in his
account of the voyage { have just mentioned, has given a
just eulogium of the surgeon of the Solide, Mr. Roblet ; and
when Iwas at the Isle of France I had an opportunity of
becoming acquainted with this gentleman, and receiving from
him a confirmation of the useful hints here given for the im-
provement of nautical medicine, which is so greatly indebted
to him. His happy employment of warm sand baths for the
eure of the scurvy at sea, and the striking success with which
it was attended, confirming that of Mr. Bellefin, surgeon of
the Naturaliste, must render his name dear to every lover of |
the art and friend of mankind.
While paying to this gentleman, equally learned and mo=
dest, the tribute of praise due to him, I cannot avoid notic-
ing a remarkable expression of Vancouver's, well adapted
to show the importance of such services, too little known
and too soon forgotten. After having spoken of the improve-
men tof this branch of physic, which he ascribes particularly
to the beneficient genius of Cook, he adds: “it is to this
inestimable improvement, that Britain is in great measure
indebted for the high rank she at present holds among
nations.” mt
If we must learn the principles of preserving the health of
seamen from a nation, to which men are so valuable, because
its population is so greatly disproportionate to its establish-
ments; it belongs to the celebrated Society*, to which I have
the honour of addectsin g myself, to make them 7 and
render them useful to our country.
Table of Experiments made to ascertain the relative propore
tigns of humidity i in different parts of the ship le Geographe.
Meteorological Oct. the 22d, 1800, at noon, lat. 49° 36’ N., long. 6° 44’
observations at yy, [4° 24’ W. from London], after several days of tempes=
sea.
tuous.weather, that did not allow the ports to be opened in
any part of the ship.
* The Medical School of Pari is, in whose memoirs this paper ia In-
ic :
On
SSE OF METEOROLOGICAL OBSERVATIONS TO NAVIGATORS. 63
Thermometer. Hyer.
Cent. Fahr.
On the peop BVeDOC oo dEeeoeHeOvE SE 8°5° 47°3° 78° Meteorological
In the gunroom, the ports shut ...... 14°55 581 96 re
Oct. the 23, at noon, lat. 48° N., long. 8°43’ W. [6°23’] ;
the cessation of the tempestuous weather having allowed the
. ports to! be opened, and the different parts of the vessel to be
cleaned,
Dpthe poap os. cwcsscccccvcrevsere 11°. 52°F. ' 95
De Me SUNTOOM 6 hi. p eee pees oeccesee. 19 55'4 89
Nov, the Ist, at 8 A. M., in sight of the island of Teneriffe,
MBOUHS MEAP 2 dive ce ce vecescccess IGE ‘G17. 78
In the gunroom, the ports open ......°17°5 63°5 8?
Under the between-decks..........-- 18°95 653 85
In the hold... s..secepecessecerss 18:9 66:02 90.
Nov. the 19th, at 8A, ML, lat. 13° N., long. 22° W.
[19° 40.})
QAR OP! L552 5)0i06' ee g62 Sale oe ee 1 69°38 93
In the gunroom, the ports. open ...... 22 71°6. 94
Under the between-decks.......0-+52 22 716 96
DIAMOND 2500S. cecwelscceesccccse 2455. 7O'E 98
Noy. the 22d, at noon, lat 8° N., long. 20° W. [17° 40°].
NS ata Badin 5 wlslod oais odie wieals Us ges SA8 TE. QO
- Betweendecks™.......cccseveeseese 24°54 75°92 94
Gunro0m .eesosveorerrsnsceceecve 249 76°82 92
MARIE ieho's ov od bee U EW esliee d PISO! 'FOGR GF
Noy. the 30th, at midnight, lat. 6° 38’ N., long. 19° W.
[16°40'}.
POR Wi isle eke eee veccnsc- 926 © 7968 99
Between-decks ....0eceeseersese008 23 73°4 98
Gonroomd .esseeecsoveversoevscene 24 ©6752 «6-96
BON Gah vias ceedeleseeresss BEB 90-7. 96
Dec. the 10th, at noon, lat. 2° N., long. 20 W. [17°40'}.
MND Boece cb bbe ebcsresiesoeescs 21S. 71°24 08
— Between-decks .....essesceseceeees 225 72°5 98
MPMMTOOMION, o0'cs tia sccedesadsessssece 223 F7O14 O6
Hold 2... ecscecececverecesescess 23°7 7466 101,
'* Here and throughout the remainder of the table, the expression
is changed by omitting the preposition : but, as it is omitted equally for
the.other parts, I suppose the author means the'same hereby entrepont
‘simply as before by sous Ventrepont. C. The
ae
64
Meteorological
MSE OF METEOROLOGICAL OBSERVATIONS TO NAVIGATORS,
Thermometer. Hygr.
pea Cent. Fahr,
The same day at midnight, lat. and long. the same.
noninbismmameioil eoeoeoeeroeseeaeeeeeereneeneseeue 19°8° 67°74° 97°
sea.
Between-decks ..0..seeessececevese 23°56 74°48 100
Gountoom | 22.0... ad secs cueeldeeaeet@QiDle patGa0g7
BRON | pon 6. Sola be Ss cals aie ale OIGAe oleh wikt UN Sent ee EET AOS
Dec. the 21st, at noon, lat. 11° S., long. 31° W. [28°40’].
POOP Crise ccteccwecsebetesssossee Sh 69°S OI
Between-decks wccsececsccvcvcesvee 214 FOZ Q5
Gunroom Set T Se ee e aass ee SIS, MOAR arog?
ERpTa SU. . Soe cae e eke se bee cme 73°4° 100
Tke same day at midnight, lat. and long. the same.
Poop eddie. 2280. sevceee ees shes aaRoiaberGr D1
Betweenedecks ib. sevccesgcice sock «22+ ~ntgieO: S196
GUDTOOM sgerececcccnececrecsvecee 21 69'S. 90
Fold cc cGaple ciss.cip omelaele s oan devin SRS "Oe Eee Las
Dec. the 30th, at noon, lat. 23° S., long. 26° W. [23°40'].
Poop wid'fi. cc biecc en cscs ddulcleblees HOM mGmeEa gon
Between-decks ....e.eeeccccdenceee 20 68 92
Ganroonts i} isis SSM ia Sain 0s wale eee ow AOD Ghee ot
The same day at midnight, lat. and long. the same.
Poop <b Gisind ibis lec ws cepalblae acts Bd eee
Betweenedecks \..... ..ceceesceceeee 19'S 66:74) 95
GUNTOOM fe 6 cede Sew esene neers roee 196% 1 O7rdGe@4
Jan. the 10th, 1801, at noon, lat. 30° S., long. 21° W.
{18°40'], . .
POOP .cccececeseecccccccesevccoes 18°5 65:3 81
Between-decks ...... o vere eeegele os ude ae
Ganroonnr et vein? S60 8a, oe mia gern le cies ok OD ee 4
The same day at midnight, lat, and long. the same.
Poop .< 468 .ccags sa sena edaiset » MAN “Gisb2: 168
Between-deckS we.eeesceeeecscccess 20°2 68°36. 89
Gmproom ..-deceeeeereccesescesss IVA. 63°32 90
_° Jan. the 20th, at noon, lat. 33° S., long. 3° W. [0°40J.
Poop 22 secede wencesscccencsnces 15D . , SODue80
Between-decks ‘occ. cceeuscecccccces 15'S. 60°44 85
Goa Broomn: |, oc'e <weileindin denies geet nine eu bo 60's 9 83
PA has bi ic ab eis cleidalitemallaisseal Paige
The same day at midnight, lat. and long, the same.
Poop, .ssecrsccvesevcenetes Hovde.) RONGW SEBS 170
Between -deck.
USE OF METEOROLOGICAL OBSERVATIONS TO NAVIGATORS. 65
Thermometer. Hygs,
ii Cent. Fahr.
Between-decks eoeeeeteoeoaeeseeeeeeeeee 16°5° 61°7° hi
ET salts 6s 0.04 + 0 014 60a “eee Loe 5o7S... 78
Janu. the 30th, at noon, lat. 35° S., long. 7° E. [9°20] ~
OM Ragin chopsccccccccessecsesess 10° 61°88 92
Betweem-cecks <....esesseerecceces 10°7 62°06 Q1
BO ccc scecerscceseeusses Log, 0°02 89
The same day at midnight, lat. and long. the saine.
PU ietinidcpa se cess desvensecsae, 1477-5840. 102
RECS ss odin o-oo ns owwinarcrencs A7ia., eld .O8
DMS te Sc gncscccrpereess 190: 02°08. 9D
General results.
- On comparing these different observations we find, with General con-
respect to the temperature, a
1, That the temperature of the air im the interior of the Temperature.
vessel is generally 3° or 4° [5°4° or 7°2° F.], higher than that
of the exterior air.
_ 2, That the difference of temperature between the gun-
room and the between-decks was scarcely 1°[1°8° F.], when,
by opening the parts and employing windsails, care was taken
to keep up a salutary current of air in the gunroom.
_3, That, circumstances being the same, the hold of the
ship is the hottest part. The exceptions to this rule appeared
to me to correspond with its being washed out, which was
done by introducing into it repeatedly large quantities of
water, the happy effects of which were both to clean and to
cool this place.
With respect to moisture we find from the preceding exe Moisture.
periments,
4, That there is habitually more dampness in the vessel,
than in the open air. |The few exceptions to this rule de-
pended on slight variations in the atmosphere, by which the
outer air was naturally affected sooner than that within the
ship.
5, That the difference.of moisture between the air within
and without the ship is generally greater than that of the
temperature, it frequently amounting to 10° or 12°.
6, That, circumstances being the same, the gunroom is less
Vou. XXXIJL—Sepr. 1312, r damp
66
Two young
vicunas
brought to
Spaine
Death of the
female,
_ and soon after
of the male,
ACCOUNT OF THE VICUNA.
damp than the between-decks, and this singular result ap-
peared to me to be owing entirely to those fatal inundations
which were employed daily between decks, while the gun
room was cleaned dry, the vicinity of the ERY SRT preventing
the introduction of water there.
7, Lastly it follows” from the cpeeeuia that, if the hold
be the hottest part of the vessel, it is also the damapest, and
that on both accounts it ought to be considered asthe most
unwholesome.
IX.
Account of the Vicuna: by Mr. Larrey, Physician in Chief
of the Imperial Guard, one of the Inspectors General of
Military Hospitals, &c.*
A. Merchant of Cadiz, a lover of natural history, brought
from Peru two young vicunas, a maleand female. He first
landed them at Cadiz at the beginning of the year 1808;
and toward the end of April in the same year conveyed them
to Madrid. They did not appear to be inconvenienced by
the change of climate, or difference of food, till the weather
began to get very hot. They were very badly lodged ina
small, dark room, not well ventilated. In this hole I had an
opportunity of seeing them, examining their figure and gait,
and studying their manners and habits.
The female, which was larger and older than the male,
being about three feet high, died soon after, during a short
tour I made in the neighbourhood of Madrid to inspect the
hospitals. I could not learn the cause of her death; but, as.
the body quickly putrefied, it was thrown into the fields.
On my return I hastened to visit the two strangers, but
found only the male, sad, dejected, and uttering plaintive
cries at the slightest touch. He ate but little, and remained
constantly squatted on his four legs: but he appeared better
and more lively in the cool of the evening and morning,
which he seemed to seek; while in the heat of the day he
Sonnini’s Bib}, Phys. Econ. Sept. 1809, p, 168,
was”
ACCOUNT OF THE VICUNA. 67
was overcome, and breathed with difficulty. Thus melan-
choly and unwell he passed the first week of June; and
about the 15th symptoms of inflammation appeared, a few
days after whieh he died.
Foreseeing this event, I had obtained permission of the Dissection of
owner, to dissect the animal after his death, and dispose of oe ae
his skin, My first care was to remove this with due cau-
tion, that I might be able to preserve the natural shape of
the animal in stuffing it: after which I proceeded to examine
the viscera, the articulations, and the general disposition of
the muscles.
_ On opening:the abdomen I found the linea alba, or apo- Linea alba,
neurosis uniting the large muscles, was extremely strong,
and much thicker than is usually observed in other quadru-
peds.
Tne viscera of the abdomen exhibited marks of the in= Abdominal
flammation I have mentioned. The stomachs were dis- ‘°°
tended with gus, and the mucous membrane inflamed.
The epidermisof the ruminating stomach had already peeled
- off, and-the intestines were nearly in the same state. There
was no urine in the bladder. The epiploons exhibited no-
thing but very thin membranous skins destitute of fat.
The distribution and figure of the stomachs were the Stom hs.
same asin the camel. The second [le bonnet] was full of
vesicles, from which a serous or aqueous fluid issued
abundantly. The paunch and the other two stomachs did
not differ in the interior form of their cavities from those of
the camel. The cellular stomach [Ja poche d cellules] was
remarkable for the internal arrangement of the cells; they
having apertures of communication furnished with mem-
branous valves, which no doubt may still be discovered in
the dried stomach of the animal. The last stomach is united 7, sestines,
to a portion of intestine, which may be considered as the
~~ duodenum. This was continued in another intestine of
~ equal bulk, which, after forming an arch in the circumfer-. ,
énce of the abdomen, terminated in the left lumbar region:
in a cul-de-sac.; whence issued another intestinal tube, very
“slender and smooth, and forming ten or twelve concentric
circles in the space made by the former. The circumvolu-
mon mesentery. This slender
F 2 intestine
+
tions were attached to a com
68
No worms in
them,
Liver.
No gall blad-
der.
and to the corresponding dorsal vertebra.
ACCOUNT OF THE VICUNA.
intestine afterward made a thousand circumvolutions in the
abdomen, terminating at length in another cecum, without
an appendage like the former; whence issued a portion of
intestine of considerable bulk, which, after forming two or
three curves in the manner of a colon, terminated in the
rectum.
Thus it appears, that the vicuna has three sets of intese
tines, the first and third large, and the middle slender.
I met with no worms in the intestines, the infinite wind-
iugs and intersections of which would appear favourable to
their formation.
The liver, which I did not at first perceive, was found
deeply concealed behind the stomach, and attached by very
close membranous ligaments to the crura of the diaphragm,
It was of very
small bulk, of an oval figure, Hlattenned transversely, and
exhibiting two lobules at its anterioredge. It was destitute
of a gall bladder; and the bile was taken directly from the
* liver by a duct, that conveyed it into a portion of the duo-
Spleen.
| Lungs,
Heart.
denum. This duct and the vena porte crossed each other.
The spleen, which was likewise very small, and of a
rounded form, was situate in the left lumbar region, contigu-
ous to the kidney of the same side. These two organs were
enclosed in one common duplicature of the peritoneum.
‘The lungs exhibited nothing remarkable. They partook
of the general inflammation, and the bronchie were filled
with a frothy sanguineous fluid. The trachea and larynx
had the same figure and organization as those of the camel.
The heart, which was of a size proportional to the ani-
mal, formed almost a perfect cone; only its point, which
was very accute, curved upwards and to the left, and the
cavity of the ventricle on that side reached to the point.
I did not see the brain, as I wished to preserve ale skull
entire.
After having examined the viscera of the animal, I pro-
ceeded with the dissection. The cartilaginous state of the
extremities of the bones did not allow me to make an arti-
ficial skeleton of them. ¥
Among the bony parts of the thorax the sternum merits
some attention. “It is in a horizontal plane, like that of the
camel,
ACCOUNT OF THE VICUNA. 69
camel, thick, rounded on its outward surface, and covered
in the natural state with a fatty substance of a close tex-
ture. The integuments on this part are much thicker than
elsewhere. This bone was intended to serve as a point of
support for the animal when lying down; and the almost
constant use he made of it during his. illness had pressed the
extremities of the sternocostal cartilages inwards. The Humpon the
middle, spinal apophyses of the vertebrze formed a gibbosity, >2ck+
which, if it had been covered externally by a little fat,
would have resembled the bunch of the camel. The re-
mainder of the vertebral column inclined imperceptibly
toward the pelvis, which was of itself inclined and of small
capacity. The edges of the haunch bones were cartilagi-
nous, The sacrum was lengthened by a series of caudal
vertebrae, so as to form a tail in every respect similar to that Tail.
of the camel,
The scapulz, very thin and without clavicles, were con- Shoulder
nected with the trunk only by means of scapular muscles, >!4¢s-
as inthe camel. The cervical vertebree formed a very long Neck,
column, curving from below upward, soas to give the neck
the same figure and length in proportion to the size of the
animal as those of the camel. Asin the latter these vertebre
had no spinal apophyses ; but a very strong cervical liga-
ment, extending from the occiput to the spine of the first
dorsal vertebra, supplied their place for the attachment of the
muscles, and kept the head and vertebre in their proper
position, The anterior face of these vertebre had a longi-
tudinal hollow, adapted for the reception of the trachea and
cesophagus.
The head of the vicuna has the same shape and external Head,
characters as that of the camel. The jaws have the same
number of grinding teeth. The lower has only four cutting
teeth, the middlemost of which are the most prominent.
The upper has none, as in other ruminating animals,
The fore and hind limbs in every respect resemble those Limbs.
of the camel.
The joints of the limbs form a perfect ginglymus, ad- Joints.
mitting a.direct and complete flexure of one part against
the next, so that this animal, like the camel, bends all
his four legs underneath his breast when he lies down:
and
Feet.
Ears.
Wool,
Manners.
A little camel.
Mode of
hunting it.
ACCOUNT OF THE VICUNA,
and this double flexure is the effect of the natural structure
of the limbs, as in the camel, which I had an opportunity
of studying in Egypt, and of examining from its birth to
its adult age. It is not therefore the result of training.
The feet of the vicuna are terminated by two, long, narrow,
soft soles; and have much resemblance to the feet of young ©
camels, i
The outward figure of the head perfectly resembles that
of a young camel, except in the ears, which are erect and
smooth like those of a kanguroo. The neck, body, and
limbs are similarly disposed; and the body, like it, is covered
with a fawncoloured, silky wool, but of extreme fineness.
From it may be made stuffs as soft and fine as the shawls of
Casimire. This tufted fleece keeps the animal so warm,
that it seeks and prefers for its habitation the summits of
mountains covered with snow. If the ears of this animal
were uniformly cut, it would exactly resemble a camel two
or three months old.
The vicuna has the same cries as the camel, the same gait,
and nearly the same disposition. It is extremely shy and
timid. It utters plaintive cries at the least unpleasant sen-
sations; and when too much alarmed its eyes are filled with.
tears, ‘Fhe very active movement of its tail and ears indi-
cate its different sensations. It is very gentle and caressing
when tamed, |
The resemblance the vicuna bears to the camel in its ex-
terval figure, internal stucture, and qualities, would lead
me to call +4 camelus parvus auribus rectus, the little camel
with erect ears.
The owner of the animal gave me the following account
of the Peruvian mode of hunting it.
The vicunas commonly inhabit the frozen summits of the
high mountains of the Cordilleras. Several of the inha-
bitants assemble together to hunt them. They first sur-
round the mountain where they are most numerous; and by
means of mournful cries, or the discordant sound of large
wind instruments, as hunting horns, they terrify the animals,
who take flight to the summit of the mountain, where no
doubt they suppose themselves inaccessible. Here the hunt-
ers form a line of circumyallation with stakes, on which are
snall
IMPURITY AND MANUFACTURE OF SODA. 71
small red flags. These stakes are connected with each other
- by cords placed pretty close. Two or three hunters then
attack the herd, which disperses. Frequently some of the
vicunas are surprised, and the rest rush down the moun-
tain, but as soon as they reach the fence, instead of leaping
over it, which they might easily do, terrified at the colour
of the flags, they crouch down in the snow, or in holes, where
hunters posted for the purpose easily take them. After
tying their legs, they carry them to a convenient place, to
sheer their fleeces. If the animals be old, they let them
loose: if young, they take them to their huts, keep them, pomegticateds
and train them to carry burdens, loading them in the same
/ manner as camels. They cannot live in the burning plains
of America, and accordingly the inhabitants of the mountains
alone can keep them. This no doubt is the reason why the
animal has been hitherto so little known.
When the animal is young, its fiesh is good eating; but Flesh and
the wool is justly in high estimation. The merchant as- sa
sured me, that it was seldom sent to Europe pure, being coos
almost always mixed with other wool of less value. adulterated,
I think with him, that it might be naturalized and breed The Pyrenees
in the Pyrenees, on the summit of which the snow scarcely adapted to it,
ever thaws; particularly as the pasture there is excellent.
X.
Observations se the Hydrosulphate of Soda, and improving
the Preparation of the Soda of the Shops: by Mr. Figuirr,
Prof. of Chemistry at Montpellier*,
| HE ist vol. of the Ann, de Chim. contains a note by pidrosulpuret
Mr. Vauquelin on hidrosulphuret of soda accidentally found of soda found
by him in the mother water of a solution, from which he as lay
had obtained crystals of carbonate of sodat. The soda he
lixiviated was from the manufactory of Messrs. Payen and
Bourlier ; and he supposed, that they had not employed car- Apparent
bonate of lime enough to saturate all the sulphur arising from source of it,
* Ann. de Chim, vol. LXIV, p. 59.
+ See Journal, vol. I, p. 303.
_ the
IMPURITY AND MANUFACTURE OF SOD4«
the decomposition of the sulphate of soda by charcoal ; and
. that this was the cause of the formation of the hidrosulphuret.
But it exists in
thecrudesoda.
Sulphuretted
hidrogeu
evolved in
preparing
Rochelle salt,
!
A lixivium of
soda set to
crystillize.
Two sorts of
crystals from
the mother
Water.
This was prebably the case, and no doubt. those manufac-
turers availed themselves of the discovery of Mr. Vanquelin.
The following’ observations however show, that the hidro-~
sulphuret exists also in the soda obtained in the combustion
of the plants, that furnish this alkali.
On saturating a lixiyium of Alicant soda with the tartar-
ous oxidule, in order ‘to prepare thé tartrite of soda and
potash, during the effervescence I perceived a very evident
smell of sulphuretted hidrogen gas. Reflecting on this, I
imagined the evolution of this gas must be owing to the de-
composition of some hidrosuiphuret, contained in the al-
kaline lixivium; and I determined to make some experiments.
for the purpose of satisfying myself on this head.
' Taking a certain quantity of the lixivium, I evaporated
it so as to separate the greater part of the carbonate of soda —
by crystallization. After it had stood at rest a few days, 1
decanted the liquor, and put about two quarts into a glass
vessel, which I placed on a shelf in my laboratory. After a
month I examined it, and found the bottom of the vessel
strewed with crystals of a colourless transparent salt, in
‘ yectangular tetraedral prisms, terminated by quadrilateral
One hidrosul
phuret of soda.
pyramids. I likewise observed octaedral crystals with.
rhombic bases. The supernatant liquor, being decanted |
and evaporated, furnished afresh quantity of the same salt, i
differing only in being coloured, and in the octaedral crystals
being less abundant. The geometrical figures of these crys-
tals led me to presume, that they were a mixture of hidro-
sulphuret and carbonate of soda, the latter being the smaller
quantity. The prismatic crystals, being separated from the
others, exhibited the chemical characters of hidrosulphuret
of soda. They had an acid and caustic taste; followed by
considerable bitterness. They diffused a slight smell of
sulphuretted hidrogen gas; and acids poured into a solution
of them expelled this gas in some quantity. Not fused,
they gave a green colour to blotting paper. With the solue
tions of sulphate of iron and of copper they threw down, a
black precipitate, as well as with those of acetate of lead and
nitrate of silver. On pouring an acid on the saline crystals
in
IMPURITY AND MANUFACTURE OF SODA. Vo
in the state in which they had been taken out of the evapo-
ratiug vessel, a brisk effervescence took place, arising from
the extrication of carbonic acid and sulphuretted hidrogen
mixed. Willing to satisfy myself whether the formation of This not form-~
‘ ; ., ed during the
hidrosulphuret of soda had not taken place during the boil gojjing,
ing of this alkali'to extract the carbonate, I took 3gr. [46grs]
of powdered soda, put them into a phial, and poured on them
muriatic acid. This produced a brisk effervescence, and a
very strong smell of sulphuretted hidrogen gas. On passing
this gas; by means of a tube, through several solutions of
metallic salts; the oxides were precipitated of the same co-
Jour as they would have been by sulphuretted hidrogen gas
obtained: from the decomposition of sulphuret of iron by
sulphuric acid.
From a mixture of érpadiinea tartarous acid in powder sutphuretted
and soda sulphuretted hidrogen gas was equally evolved, > ener
. These experiments were made with the various sorts sold in Ae speci:
the shops under the names of Carthagena soda, kelp, and mens.
barilla. They all presented the same results,
It cannot be doubted therefore, that the hidrosulphuret Crude soda al
of sada is contained in all the kinds of soda ; and that it may ore ae
be obtained from the mother waters of the lixiviums, that hidrosulphu-
have furnished carbonate of soda. The formation of this salt "
is easily understood. When the plant is burned for procu- Source of it.
ring the alkali, the fire is urged so far as to causé the ashes
to undergo a semivitrification: the sulphates contained in
them are decomposed by the action of the charcoal: the sul-
phur is liberated and forms sulphurets. At the same time
there is an extrication of hidrogen gas, which may be furns
ished by the charcoal itself, or by the decomposition of the
plant or of water ; and no doubt by the three together. This
hidrogen gas, uniting with the sulphur, constitutes the sul-
phuretted hidrogen gas, which in its turn combines with a
part of the alkali, and forms hidrosulphuret of soda.
The formation of the sulphurets and hidrosulphurets that The prepar-
barilla contains being occasioned by the strong calcination ria
sof the ashes furnishing this alkali, we may infer, that the
-method of preparing it is defective. It is evident, that part Inconyeniene
of the alkaline salt enters into the const:tution of the sul- °& of it
phurets and hidrosulphurets contained in it, These remain
ip
Farther incon-
weniences.
Biethod of .
gwodin g these.
,
Serious acci=
dent in. a soap
mamufactory.
IMPURITY AND MANUFACTURE OP SODA.
in solution in the mother waters, that have furnished carbone
ate of soda. When the barillais employed for making soap,
the same loss is experienced. ‘The soapboiler’s lie contains
sulphuretsand hidrosul phurets, which diminish its causticity,
as they have a weaker affinity for lime than for soda. The
consumption of this alkaline substance in pharmacy, and
more especially in soap-making, is sufficiently extensive, to
turn the attention of chemists and manufacturers to an im-
provement in preparing this alkali; whieh is also much
employed in dyeing cotton, and in the washhouse. In the
latter, the sulphurets and hidrosulphurets in barilla not only
render it so much the dearer, but are injurious to the white-
ness. of the linen and cotton*.
These are not the only incouveniences arising from the
high degree of heat, to which the soda is exposed in manu-
facturing it. A still greater is, that a part of the alkali enters»
into combination with the earthy substance contained in the
ashes, and forms a kind of frit, indecomposable by the action
either of water or of acids ; and the quantity of alkali wasted
wm forming this semivitrified substance is greater than that
taken up in the formation of the sulphurets and hidrosule—
phurets. Here no doubt is a great loss of alkali, occasioned
by the semivitrification of the ashes of the plants that furn-
ish soda; and which would be avoided by adopting the mode
used in preparing potash ; lixiviating the ashes, evaporating
the lixivium to dryness, and selling the alkaline salt in this
state of preparation. The consumer would find so much
* The sulphurets contained in unprepared soda frequently occasion
serious accidents in soap manufactories. In these, where it is custom-
ary to keep caustic he in large covered stone vats, the sulphurets de-
compose the water. The hidrogen not absorbed by the hidroguretted
sulphurets thus formed occupies the empty part of the vat. When
the workman takes off the cover, to dip out the lie, and holds in his:
hand a lamp to light the inside of the vat, the hidrogen takes fire, and
endangers the building. In a visit I just paid to Marseilles I saw one
of these manufactories, that had been destroyed by a violent explosign
of this kind. The hidrugen being mixed with atmospheric air such
anexplosion took place, that the house was near being thrown dowm
he owner, supposing the manufacturer had maliciously attempted to
destroy hishouse, summoned him befure the magistrate; and the eause
is still pendjng before the first tribunal of the de partment,
\ the
RED BEET RECOMMENDED FOR CATTLE. “5
_ the more advantage in this, as it would be easy for him to
‘satisfy himself of the purity of the alkali; a knowledge so
“necessary to the success of various processes both in phar
macy and in the arts.
But what are the reasons, that have induced the manu- Refections oe
facturers of barilla to give it this solid consistency ? Is it the manufac.
‘because in this state it is more convenient for carriage ? or ee
because it was originally less used in the making of soap than
of glass? It is true, that in the glasshouse there are fewer
inconveniences from its use, than in the processes of chemis
try and the other arts. When the crude alkali is employed
in making glass, not only are the hydrosulphurets, sulphu-
rets, and other salts it contains, decomposed by the high
‘heat required in this process, and their alkali serves as a
flux; but the frit itself enters into the state of vitrification,
and thus adds to the bulk of the glass. This, however, can-
not be considered as an advantage; for it is certain, that ba-
rilla contains nearly four fifths of its weight of heterogeneous
substances, which of course increase the expense of carriage
in this proportion. This is a consideration, that claims the
attention of the consumer. The first source of, profit in a Hint to mane-
manufactory is economy in the raw materials, Roctinresa
~
4
XI.
An Eesay on the Cultivation of the Red Beet, by Mr. Gor-
RING, @ Saxon Agriculiurist®.
Nexr to the potato, the utility of which is well known, Red beet very
the red beet is one of the most beneficial plants, the culti- see at
vation of which is particularly to be recommended. Everyone Yields much
knows, that sugar has been obtained from it not inferior to good sugar,
that of India ; and the manufacture of which would probably
have been established in Germany, had not the consumption but this con-
of wood necessary for it checked its most zealous partisans ; 5U™66 too
much wood.
for the resources of Germany in this respect are daily di-
yainishing. :
¥ Sounini’s Bib. Phys. Econ. May, 1810, p. 289.
Beside
76 RED BEET RECOMMENDED FOR CATILE.
Other propere Beside this essential point, which cannot be attained from
ties of it, Jocal difficulties, and which may not exist in many other
countries, the principal properties of the beet are those of
being nourishing, emollient, cooling, laxative, &e.
Advantageous Supposing it to be cultivated only for feeding stock, par-
ae feeding cat- ticularly cows, in winter and in summer, it deserves in every
respect to be preferred to most plants both for the root and
White beet in- leaf. Though the white beet is of pretty extensive use, and
jures themilk: much cultivated, it cannot in any respect be compared with
the red. It is neither so firm nor so sweet; and we find by
experience, that the milk of cows fed some time with it loses
its sweetness, and becomes bitter. Besides, it can scarcely
be kept through the winter, as it soon grows rotten.
the red beet The red beet on the contrary is firm, sweet, and but in a
improves it. moderate degree watery, It is at least as nutritious as the
turnip cabbage, and imparts to the milk a pleasingsweetness,
which continues as long as the cow is fed on it. It keeps
very well through the winter, either in cellars or in pits, pro=-
vided it be not put in wet; and is as fresh when taken out
in the spring as it was when laid up. They who cultivate
both sorts, therefore, should use the white in the fall, and
keep the red for the spring.
The leaves The leaves of the red beet, which may be gathered in the
good fodder. niddle of july, the time of sowing the white beet only, is ex-
cellent fodder, particularly for horned cattle and pigs. It is
true however, that the leaves cannot be thus gathered but at
the expense of the roots.
& crop to be It is also indisputable, that the red beet is one of the roots
depended one that succeed almost always. It has few enemies, and a good
crop may always be depended on, provided the ground has
been well tilled and prepared, and the seed properly sown.
May be sown ‘There is no season amiss for sowing the red beet, It may
abany mes be sown as early as you please in spring, or even in autumn;
for the first leaves which in most other plants are very ten-
and no insect ef are able to stand the cold winds of spring. No insect
tajurcs it, can hurt them ; and while the turnip, the turnip cabbage,
the cabbage, &e., are destroyed by the leaflice, the red beet
grows astonishingly: and when in autumn the leaves of those
plants are devoured by caterpillars, none are seen’on the retl
beet,
The
RED BEET RECOMMENDED FOR CATTLE. eA
The only enemies it has, that I know of, are fowls; for Fowlsex-
3 ; . le tremely fond
these are so fond of its leaves, as entirely to lay waste the oe: ag
fields of it, to which they can have access. Their appetite
for this plant, when they once have discovered it in a field
or garden, is such, that it is almost impossible to keep them
‘out. They should not be sown therefore in gardens or fields
too near houses, asin this case the crop may be looked upon
as lost.
The following is the method I have adopted of cultivating it.
I first select, if possible, a good black mould, rather rich. Method of
If itbemixed with a little sand, and provided it has not too Cting &~
much clay, it is good for the beet, which always requires a
little moisture. it may be cultivated indeed on light ground,
_ but not with equal success,
_1n autumn I lay on manure, in the proportion of six two
horse cart loads of dung of horned cattle to a hundred and
forty square perches.. This dung I afterward bury at least
six inches deep with the plough: and then [ give the ground
another ploughing in narrow furrows.
As soon in the spring as the land can be worked, | sow
the eed where the plants are to remain; for experienee has
taught me, that transplanting them is injurious. They
a
should not be sown too thick: there should be at least six
inches distance between the plants; and it is often necessary
to pull up some in the thickest places, for three or four
plants frequently spring from a single seed.
It is usual to cover the seed by raking or harrowing: but
as from their lightness they frequently lie on the surface
and rot, it is better to use the hoe, or the plough, taking :
care notto bury them toodeep. In this way we may be cer-
tain of their germinating quickly, if the soil be good.
As soon as the plants have their sixth leaf, they should
be weeded, and thinned out where too close. A few weeks
after they should be hoed, but so as rather to draw the earth
from them than to heap it round them.
- When the leaves begin to bend down tothe ground, the Gathering thie
largest, at the bottom of the plant, may be guithered for leaves.
the cattle: but they must not be stripped too much, as this ©
would injure the root. Nor should the leaves be plucked off
before. they separate as it were of themselves, inclining
toward the ground. if
\
78 TURKISH ROSE PEARLS«
Taking upand If weeds appear again, or the ground get hard and dry’s
Sat the they should be hoed a second time. Lastly, in the month
of Octeber the roots should be taken up, and Jaid in the
places intended for keeping them, first cutting off the stalk
close to the root, that they may not vegetate during the
winter.
IT.
Account of a Composition commonly called Turkish Rosé
Pearls; by Mr. Mancexi De Serres, Inspector of Arts;
at Vienna*.
Elegant and "Turkey has a considerable trade in a composition
fragrant black ; heen
beads made of Known by the name of rose pearls; and as this composition
rose leaves. is very simple, I imagine it may not be uninteresting to make
it known, that it may be imitated in other countries. Nothing
more is necessary than to take the petals of fresh gathered «
roses, and pound them carefully in a cast iron mortar well
polished. They are to be pounded till they are thoroughly
bruised and form a smooth paste. This paste is to be spread
on a sheet of iron, and dried in the air. When it is nearly
dry, it isto be pounded again with some rose water, and
dried afresh. This is to be repeated, till the mass is’ re-'
duced to a very fine paste, when it is fashioned into the
proper shape with the fingers, or with an instrument similar
to that used for cutting pills. The sort of beads thus formed
are then perforated for stringing, and the paste is dried afresh,
till it becomes very hard. When they are smooth and well
polished, they are rubbed with oil of roses, to increase their
fragrance and lustre. - By this simple process the paste of
rese leaves takes a very decided black colour, owing to a
combination of the gallic acid in them with iron.
Similar beads With a similar paste beads of various colours are formed.
efotherco- The most common, next to the black, are red and blue.
“ The colouring matter 1s added to the paste. It is possible
however, that these red or blue beads, which are said to be
* Sonninis’s Biblioth. Phys.—Econ. Feb. 1920, p. 105. '
nothing
ON TRE TALL OATGRASS. 79
nothing but the paste of rose leaves so coloured, may be
made of a particular paste; and if I must give my opinions
I should think this is the case, from the difficulty of giving
a red or blue colour to a paste so black as that of roses*,
The red necklaces in question must not be confeunded with
those made of pimento, or those of the fruit of the red bead
vine, abrus precatorius.
Frequently to render the Turkish rose pearls more fra» Additions te
grant, oil of roses, storax, and musk, are mixed with the their perfume,
paste; but this addition makes no alteration in the mode of
preparing it.
~ The black beads are most vied, either because they set The black ge
off the colour of the skin to more advantage, or because their Aan ad
perfume is more agreeable. These beads find their way
over Europe through Austria, and are of some consequence
as an article of trade.
. XIII.
On the tall Oatgrass: by Mr. Touuarn, sen}.
"Tue tall oatgrass, avena elatior, grows and produces an Utllity of the
abundance of fodder, both in good and bad soils. It is of ‘ll oat-grass.
very early growth, and rises to the height of two or three
feet. Its stalk is fine, slender, and makes very good hay.
_ It is mowed twice a year. If it beeaten green, it may be
cut oftener; but it is principally cut for hay.
It may be sowed in autumn, or in spring, after two plough-
ings; at the rate of 70 kil. [154 lbs] to the are [2-5 acres].
Frequently saintfoin is sown with it, in the proportion of a
hectplitre [2 bush. 3 pecks] of saintfoin, and 60 kil. [132
ibs] of oatgrass seed, to the above quantity of ground.
'# It is obvious, that this difficulty would be removed by wholly
avoiding the use of iron in making them. At the same time the petals
of other fragrant flowers of different colours might probably be used
_with advantage. Thus the violet appears to be well adapted for the
blue. The manufacturer tuo might avail himself of the well known
: property acids possess of heightening the red of roses, and of charging
~ vegetable biues to red; as well as perhaps that of alkalis, in convert-
ing the blues into green. C.
___. + Abridged from Sonnini's Journal, Dec. 1810, p. 375,
teow | os
8&0
Utility of the
tall oatgrass.
Medical and
surgical lec-
Bures:
MEDICAL AND SURGICAL LECTURES,
It is particularly adapted to horses; but all animals, that
are commonly fed with hay, eat it with pleasure.
Opinions have been so divided respecting tnis plant, that
several writers have been eager to boast its advantages, while
others have endeavoured to depreciate it. This difference
of opinion respecting a plant of real utility has arisen from
the authors who have mentioned it omitting its botanic name:
hence some have confounded with it the ray grass, lolium
perenne; others with the way bennet, hordewm muruie, which
has no relation to it, and is one of the very numerous plants
injurious to. meadows, :
I repeat, that the avena elatior is the best basis of a nae
tural meadow ; and that, when cultivated alone, it makes
an excellent pasture. It is one of the best of the family
of grasses, as any one may readily be convinced by obser-
vation. It may be known any where by its slender stalk,
rising above the other grasses, and terminating in panicles a.
little drooping.
SCIENTIFIC NEWS.
=
, St. Thomas’s and Guys’ Hospitals.
The Winter Course of Lectures, at these adjoming Hose.
pitals will commence as usual on the 1st of October, viz,
At St. Thomas's.
Anatomy and the operations of surgery, by Mr. A.
Cooper, and Mr. Henry Cline. Principles and practice of
surgery, by Mr. A. Cooper.
At Guy’s.
Practice of medicine, by Dr. Babington and Dr. Curry,
Chemistry, by Dr. Babington, Dr. Marcet, and Mr. Allen.
Experimental philosophy, by Mr. Allen. Theory of medi-
cine, and materia medica, by Dr. Carry and Dr. Cholmeley.
Midwifery and diseases of women and children, by Dr.
Haighton. Physiology, or laws of the animal ceconomy,
by Dr, Haighton. ‘Structure and ae of the teeth,
by Mr. Fox.
N. B. These several leetures are so arranged, that no
two of them interfere in the hours of aitendance; and, with
the lectures on anatomy, and those on the principles. and
practice of surgery, given at the Theatre of St. Thomas’s
Hospital adjoining, the whole is calculated to form a com-
plete course of medical and chirurgical instructions,
4
JOURNAL
' OF
NATURAL PHILOSOPHY, CHEMISTRY,
AND
THE ARTS.
OCTOBER, 1812.
ARTICLE I.
On the Electric Column, and Aerial Electroscope. ByJ. A.
De Luc, Esq. F. R. S.
To William Nicholson, Esq.
Siz,
N my last paper, published in your No. 149, after hav-
ing shown, that Dr. Maycocx had very ably refated
the natural philosophers, who thought that the galvanic effects
depended on the electrical energies of the particles of matter ;
and proved, that it was produced bythe action, on each other,
of two proper metals; I was obliged to dissent from bim on pwo points on
two points: 1. that the electrical excitation produced by the two which the au-
metals did not exist during their contact, but only at the instant fromDr-May-
they were separated—2. that the galvanic apparatus can only cock.
be excited by a decomposable fad, which is always decomposed
when the apparatus acts. But I opposed to these two proposi- His reasons
tions my experiments related in your Journal for June and Au- for this.
gust, 1810, which demonstrate, that, in the galvanic pile the
chemical effects are. independent of the cause of the electric
effects ; the former being only produced when the electric fiuid
pervades a pile, in which a liquid acts on the metals to corrode
them. Ihayeexplained, also, in the same paper, how these
Vor. XXXII, No, 152.—Ocroper, 1812. G)- ex
es)
Liss)
Spontaneons
electric ma-
chine
of unlimited
power and
duration.
Column of
20000 pieces,
by Mr. Allen.
Jav charged
by it.
Did not de-
conpose wa-
ter.
Effect of size
and number of
plates,
+
AERIAL COLUMN AND AERIAL ELECTROSCOPE.*
experiments led me to the discovery of an electric apparatus,
which, without any liquid, and’ composed only of alternate
xine plates, and equal pieces of Duich gilt paper, produces
strong electric, but no chemical effects.
2. My paper, Sir, in your Journal for October, 1810*, con-
tains the description of a small apparatus of this kind, which,
in order to distinguish it from the galvanic pile, I have named
electric column. It is really a spontaneous electric machine, the
power of which can be increased without limits, by increasing
the number of the groups: it is lasting ; for I have stili the first
column, (that represented in the figure+) which I constructed
five years ago, preserving still its power: and indeed there is no
reason why it should lose it, as there is no liquid to affect the
metals; for it requires only that the papers should possess the
small degree of mozsture of the surrounding air.
3. As to the increase of power of this, natural electric mas
chine by increasing the number of the groups, a very ingenious
and well-known experimental philosopher, Mr. W. Allen,
has carried it to such a degree as to produce very remarkable
effects. His apparatus consists of ten columns, each containing
1000 groups of zinc and Dutch-gilt paper, forming together a
series of 10,000 groups : but they are of a small size, so as to
be enclosed in glass tubes ; a circumstance, the effect of which
shall be seen. The following are the phenomena observed
by Mr. Allen, which confirm some points which I have stated.
1, Having tried to charge a coated jar, the charge arrived
sometimes to such a degree, as to give a shock up to the elbows ;
but at other times it could never arriveat that point. ‘This cir-
cumstance is owing to what I had observed of the influence of
the electrical state of the air.
2. Notwithstanding such electric power, Mr. Allen did not
perceive any production of gasses in glass tubes with water,
made to connect the extremities of these columns.
3. That apparatus shows also what I had found with respect
to the size of the plates ; that the size was indifferent to the in-
tensity of the ultimate effect; but that the larger they were,
the sooner that effect was produced. The plates cf Mr. Allen
being small, many minutes were required to charge his jar.
* Vol; xxvii, p. 81. t Ib. pl. iii,
4. 1
a , fe
AERIAL COLUMN AND AFRIAL ELECTROSCOPE.
4. I come now, Sif, to ty experiments contained in your
Journal for October, 1810, with a figure, half the size of the
original, of the apparatus to which I shall refer them, but only
in their parts concerning Dr. Maycock’s system. For these ex-
periments, beside the e/ectroscopes at the ends of the column,
there is one in the middle. 1 shall call A, that connected with
the positive end; B, that at the negative; and C, an electroscope
placed at the middle point : but by taking off the wire 4, it may
be made to communicate with any part of the column, the
electric state of which is wanted to be known; and this by
means of an insulated wire, so soft as to be easily bent, and
tlus made to connect, by one end, with the electroscope C, and
by the other, with the part of the column the electrical state of
which is wanted to be known.
5. These experiments, which begin at p.S8 of the same 7
number of your Journal, referring to some TaBLEs given in the
conclusion of my preceding paper*, I think better, for an im-
mediate reference, to copy them here, with this previous expla-
nation, that in all of them, A indicates the posz/ive end, and B,
the negative.
Taste I. Taste IT. Taste III.
Insulated Column. PBincommunication Aincommunication
with the ground. with the ground.
A A A
+ 10 + 20 0
ale + 16 — 2
+ 6 dre ent ith
+ 4 + 14 — 6
+ @ -- 12 — 8
0 -- 10 40
ro ee ob 1G — 12
calpee: sale — 14
Swe ae — 16
ara Wee + 2 — 18
B B B
6. I come now to the experiments. Experiment 7 is thus
related in p. 88 of your Journal above quoted. ** At the time
** when (on account of the electrical state of the air) there are
* simple and equal divergences in the electroscopes at the extre-
* Vol. xxvi, p. 265.
G2 ‘© mities
83
Mr. De Luc’s
apparatus.
\
Differeat
states of the
pile.
Experiments
showing the
motion of the
electric Auid
in the column,
34 AERIAL COLUMN AND AERIAL ELECTROSCOPE,
“mities of the column, then positive at A, and negative at B ;
“* there is no divergence i the electroscope C ; it is a neutral
“¢ point, and is expressed by Oin ranrn J. If, at the same
* time, any point of the column, at a distance from the point
“°C, on the negative or positive side, proportional to one of
‘‘ the terms of raBxe I, be tried by the insulated wire, the di-
** vergence produced is, as exactly as can be expected in such
“‘ experiments, correspondent to that expressed in the talle,
with its sign either — or +,”
7. In Exp. 8 are seen the two different cases expressed in
TABLES II and III, observed also by means of the insulated wire.
The case of tase II is produced by placing the end B, or ne-
gative, in communication with the ground. In this case, the
electrometer at the middle point C, which, in the preceding
case, was neutral, has a positive divergence, equal to that before
‘é observed at the extremity A, where it is now double. . There
is no neutral point perceptible, but clese to the end B, whence
the posttive state is increasing towards A, at the rate expressed
by raBLe II. If the communication with the ground be in-
versely placed at A, or the positive extremity, which is the case
of TABLE III; then the only point found neutral in the column
is close to that end A; and thence the negative state is increasing
up to B, where it is become nearly double; and at the middle
point C, the divergence, now become negative, is equal to what
itisatthe extremity B, when the column is tnsulated.
"The efecks 8. If Dr. Maycock had known these experiments, in which
produced the electroscopes indicate, to the eye, the motions of the
while the me- a Hebe Palen : ¢ F
tals arein con. electric fluid in the column, he could not have persisted in his
tact. opinion, that the metals do not produce their electrical effects
while 72 contact, and only at the instant they are separated ; for
they were not separated an instant during the course of these
experiments. Besides, Iam induced to think, that Dr. May-
cock did not-even know yet the existence of that new instru-
ment, the electric column ; or at least had not had the oppor
tunity of seeing any ; for each column, of whatever numler of
groups it is composed, which constantly remain in contact, pro«
duces electrical effects at its extremities, in proportion to the
number of groups.
This eqtally g. Dr. Maycock, not having read my papers, might say, that,
mad ahi) 1 applied his system only to the galvanic pile ; but had he
kuowa
AERIAL COLUMN AND AERIAL ELECTROSCOPE. 85
Known the same paper of which I ara speaking, he would have in the galvanie
seen, in p, 91, that I have made the very same experiments di- P°:
rectly on the galvanic pile; and that I found the same grada-
tion of plus and of minus, from the middle point, as in the
column. Only these operations cannot be so long continued on
the pile, because its electrical signs are diminishing in propor-
tion to the erosion of the surface of the metals. But Dr. May-
cock could not be informed of these electrical phenomena of
the galvanic pile ; because, as it appears, he has not used it;
and his galvanic observations have been only on the galvanic Trowaeact
apparatus of éroughs, which, as I shall show ina fittire’ paper, diferently.
has deceived him.
10, I now come to another class of experiments, which, it O¢ner proofs
seems, are also unknown to Dr. Maycock ; for, had he read of the circula-
them, he would have found evident proofs of a zrculation of the eet ee d
electric fluid, when the extremities of the column, or of the inthe pile.
pile, are connected together. These experiments consist in pro-
ducing the connexion of the extremities by different Lodies, and
observing their effectson the gold leaf electroscopes, It has
been seen, in the above experiments, that, when the extremities
-of the column are unconnected, there is an accumulation of the
electric fluid at the extremity A, where the gold leaves diverge
as positive, and a deficiency at the extremity B, where they di-
verge negatively. If a good conductor be applied to produce
the communication between thé extremities, the gold leaves
fali on both sides: if it be a perfect nonconductor, their diver-
gence is not altered : but if an imperfect conductor be applied,
they fall, in proportion to the conducting faculty of the body.
11, These experiments begin at p.Q1 of the same number Gjass ie quires
of your Journal. I made them for the purpose of ascertaining varnish for a
a very essential point in electricity, that of the best znsudation ae aes
of all our electrical apparatuses ; having found, that the want’
of a complete insulation may lead toerrour. Glass is the only
body used, on account of its solidity, for pillars in all these
apparatuses; andit has, inthis respect, the essential property
not to be permeable to the electricuid : but.it is not a perfect
nonconductor ; the-electric fluid moves, though slowly, along
its surface, and to prevent it, it is necessary to cover it with
some insulating varnish. These experiments, therefore, I
made first, in order to find out which were the best conductors ;
next,
86 AERIAL COLUMN AND AERIAL ELECTROSCOPE.
next, what was the best insulating varnish to cover glass ; and
in their course I ascertained the different conducting faculty of
various bodies. ;
poe ayae on! 12. The general results of these experiments were, that with
pa ike on respect to the Lest conductors, the glass tubes with water and
proper wires, when no chemical effect is produced in them, are
sensibly as good conductors as metals. As to the insulating
faculty, I found, that sealing war, in which no spirit of wine
is added to make it softer, being laid on glass rods sufficiently
heated to melt it, is equal to the best other varnish ; for when
placed on the extremitiesof the column, with tag precautions
T have indicated (the want of which produce very remarkable
‘ phenome: a) these rods do not affect the divergence of the gold
leaves. Lastly, | have given many details of my experiments
on intermediate bodies, showing that, in proportion to their con-
ducting facully, each praduces a determined degree of diminution
_ in the divergence of the gold leaves.
ee , 38. The whole of these experiments affords such proofs of a
circulation of circulation of the electric fluid in the column when its extremi-
the fluid, ties are connected together, and consequently of its motion, that,
if Dr. Maycock had known them, he could not have had any
doubt of these effects. The circulation is in consequence of an
accumufatzon constantly tending to be produced on the positive
extremity, at the expense of the other. This tendency con-
tinues, though the extremities ‘are connected together ; but the
electric fluid cannot accumulate on the positive, while a good
conductor can transmit ‘it’ instantly to the zegative ; whence it
also instantly returns to the positive, by the property of the
column. But if the intermediate body be an imperfect conductor,
the circulation is oe and some seibdhie signs remain at
the extremities. ' ~
Phe electrical +. 14, There is another set of my experiments, whieh might
sctionnot Bade have made Dr. Maycock doubt of the very ground of his sys-
tem. ' He has imagined a certain property producing the elec-
trical effects; such, I suppose, as that of the magnet ; which,
in consequence, ought to act suddenly. If this were the case,
when a Communication with the ground has changed the diver-
gences ‘of the gold leaves, that communication being removed,
the same divergences ought to be suddenly restored; but it is
ou ies uta as py be seen in Exp. 4, 5, 6, of the same paper.
. ? peer
AERIAL, COLUMN AND AERIAL ELECTROSCOPE. 87
There is some sort of impediment to the motion of the electric But progres
fluid along the column, probably caused by a reluctance in the Ve.
xine plates to part with the superior quantity of electric fluid
they must possess when united with copper, to produce.
their. electrical equilitrium. The consequence -is: that,
after having observed the divergence of the gold leaves in both
electrometers, if one of the extremities of the column be made
to communicate with the ground ; by which the gold leaves fall
on this side, and they diverge more on the other side; it requires
along time, in some cases many hours, for the same divergences
to be restored. .
15. There is an entertaining experiment, which may lead _ to Similarity be-
tween the ac-
some discovery respecting the physiology of wegetatles.. Each 4:05 of the co-
of the electrometers of the column may be made to imitate the Jumn, and that
sensitive plant (mimosa sensitiva:) for, as the contact of one of the sensitive
of the extremities of the column produces the fal! of the gold
leaves on this side, which rise slowly; the contact of the sen-
sitive plant makes its leaves fal/, and they also rise slowly. ‘Vhis
analogy of slow effects, pointing out some general analogy
between their causes, must render us cautious not to assign
hastily to some vague property the effects that we may follow
distinctly in their process, suchas those of the electric column ;
for they may lead us, in time, to the discovery of causes, it
those phenomena which now appear the most obscure.
16. The Ild part, Sir, of the same paper in your journal, See null
concerns the electric column in its phenomena as an-aertal elec- enlation influ-
troscope, and contains the observations.which I had already ere
made with that instrument. This class of experiments relates (
to the opinion of Dr. Maycock, forasmuch as they prove, not
only a constant motion of the electric fluid in the column, but
that some external cause iafluences much the rapidily of its
motions ; an object the explanation of which I had postponed.
17. These changes are seen, when the extremities of the 4s shown by
tolumn are not made to communicate immediately wiih each ay eee
other ; but only by the alternate strikings of a body suspended
between them, taking some electric fluid from the posztive
side, and bringing it back to the negative. Now, the more
rapidis the motion of the electric fluid in the column, the more
numerous are the sirikings ina given time; and the difference
is
$s. AERIAL COLUMN AND AERIAL ELECTROSCOPE.
is very considerable, in different days, and different parts of the
same day.
This instru- 18. When I first observed that phenomenon, it pointed out ta
ie made me a new and very interesting object of study: but, according
own imper- : i er
fectly, to a plan of observations, which I then formed, I was obliged to
make many additions to my column, which required much
time: but the first description which I had given of that appa-
ratus in a paper to the Royal Society, and of its purpose, made
it partly known.
andimitatedby 19. This accidental communication to the public was a
Mr. Forster. lucky circumstance; for before 1 could have time to do it my-
self through your Journal, a very ingenious experimental philo-
sopher, Mr. B, M. Forster, not knowing it precisely, imitated
it in acurious manner: he formed two columns, containing to-
gether 1500 groups of ximc and silvered paper, of the small size
of my first column, and having placed them horizontally, he
connected with each extremity a small Lell, and suspended be-
tween them, and very near them, asmall brass ball, held by a
silk thread. When the apparatus was ready, he heard it chime,
with a sort of buzzing noise on account of the rapidity of the
motion of the ball.
Defect of his 20. This apparatus had been mentioned in Mr. Filloch’s
apparatus, Phil. Magazine, and having seen there its description, I spoke
of it in the same paper of your Journal, p. 103. But since
that time, having had the pleasure of making personal acquaint-
ance with Mr. Forster, and.corresponding with him, he has
communicated to me, from time to time, his observations of
this kind of aeroscope,. which, though in a different manner,
indicates also changes in the electrical state of the air; for,
after having chimed for some time, it stops totally, then begins
again, and’stops ; sometimes it chimes fora moment, between
long intervals of silence.. This is a very curious phenomenon,
but there isa want of intermediary terms between the cessation
and return of motion. These inequalities are occasioned by
the insulation of the little Lad/, it being suspended by a. silk
thread. Having tried what would be the effect of a greater
distance between the bells, I found that it stopped the mation
of the little ball, and I soon judged what was the cause of that
cessation, When there is more distance, the liitle bali tending
sensibly as much to the positive as to the negative bell, the dif+
ference
AERIAL COLUMN AND AERIAL ELECF2OSCOPE.
ference between these tendencies is not sufficient to surmount
its weight, and it remains without motion; but when it is very
near each bell, a very small difference of ‘attraction on one
side can make it move towards it, whesce it is repulsed. The
difference, however, between these attractions may be so small,
that the little ball remains undetermined, even at that small
distance, though the colwmn'has a sensible action.
21, My plan had been different from the beginning, and This did not
exist
thus free from that impediment: it was to obtain a separate ). Lic:
electrometer, formed of a long brass rod with a large ball at the
bottom, and to suspend at the top, by a conducting thread, a
smail metallic ball. This small apparatus bcing connected by
its‘upper part with one side of the column, the little ball was to
diverge; and I intended to have another large ball in commu-
nication ‘either with the other side of the ccelumn, or
with the ground, against which the little pendulum should
strike, fall, and rise again. This apparatus is represented in
the figure annexed to my paper in your Journal for October,
1810. In the same paper, I explained all the difficulties which
I encountered, before I could prevent the little bail of the
pendulym from sticking to the Jarge ball. At last, however,
I succeeded by the means expressed in ‘the figure ; and having
determined the distance of the second large lail, at which the
pendulum should never cease to strike it by the smallest power
of the column, the purpose of the apparatus became to count
the number of the sirikings in a given time; which. was the
precise indication that I had desired to obtain of the smallest
changes happening in the power of the column.
Mr.
22. This apparatus was ready for observation in the begin= Observations
ning of April, 1810, and in the remaining part of the same with this ap-
paper I related the phenomena, which it exhibited during this -
month and the following month of May. The tables of these
observations are composed of five columns: the first indicates
the days and parts of the days in which the observations were
made. The second, the points at which the Larometer stood.
The third, the points of the thermometer in the room.” The
fourth that. of my hygrometer*,. The fifth, the numler of
strikings of the pendulum in determined times. 23. By
* This instrament has been taken up bya very ingenious Hanoverian
gentleman
~~
aratus
90 AERIAL COLUMN AND AERIAL’ ELECTROSCOPE.
The pheno- 23. By comparing the Jast column with all the others, in the
pie Pret paper above-mentioned, it may be seen, that there is no con
tric state of Hexion of the number of séirikings with either the Larometer,
Ser the thermometer, or the hygrometer, and only with the different
y days and parts of the day. Which circumstance confirmed
me in the idea, that it was only the different electrical states of
the surrounding air, that produced these changes in the power
of the column; however obscure was still this connexion, for
the reasons which I explained.
The inquiry 24. This isa new and very interesting subject of experimen-
lg ee a tal and even natural philosophy, and in publishing it in this its
"infancy, I hac ‘> hope that it might lead some attentive ob-
server to follow it up. This hope has been realized, when I
have seen in your Journal, that Mr. T. Forster has under«
taken that investigation ; particularly as I know his talents,
being, since that time, personally acquainted with him,
nigel 25. I shall only mention farther, that I have made a new
tus, tii’ step in this pursuit. Knowing by my former experiments,
that, though the size of the plates is indifferent to the final
simple divergence of the gold leaf electrometers at the extremi-
ties of the column, it is not the same when, one of them sétrik-
ing the side, they are reduced to the electrical state of the
ground; for they rise faster and strike again, when the plates
are larger. Applying, therefore, this result of my former
experiments to the motion of a pendulum, I have constructed
a column, which, in two connected parts, contains 1300
groups, formed of zinc plates 1§ inch square, and equal pieces
of Dutch gilt paper. This column moves a pendulum consist-
ing of a gilt pith Lall the size of a pea, suspended like the
other by a conducting thread, and placed in the same apparatus,
which prevents its sticking when it strikes the large ball. This
pendulum, guarded against the agitation of the air by a glass
case, moves between the two same large lal/s, being near one
‘inch distant from each other, and it has not ceased to strike
gentleman, residing at present at Cumberland Lodge, near Windsor;
Mr. Hausemann, he has succeeded in every point, and is resolved, from
its utility, to construct it for the experimental philosophers who shall
desire it.
during
AERIAL COLUMN AND AERIAL ELECTROSCOPE.
during alfeady two years that ithas been constructed : but the
sera of its sfrikings is also very various ; for I have ob-
served at times forty-five in a minute; but puted at other
times by all the intermediate numbers down to hardly one.
“i In this state I must leave this pursuit, on account of my
age; but I have learnt, with great pleasure, that Mr. B. M.
Bateter is employed in constructing also a column with large
plates and a pendulum; and that bis nephew, Mr. T.
Forster takes great notice of the connexions of this phanomena
with various circumstances in the appearances of the air, and
with diseases. This, in time, may lead to some useful dis-
covery, both for science and for society.
27. This new electrical phenomenon, so connected with the
state of the air which surrounds us, cannot but interest many
natural philosophers, were it only with respect to meteorology :
itis anew ¢hread leading in the maze of atmospheric pheno-
mena, provided it is not associated with gratuitous hypotheses.
This, Sir, has been the object of the IIId part of my paper on
the electric column, contained in your No. 124, for December,
1810; in which part I have given: an abstract-of some other
threads obtained in the atmospheric phenomena, considered
both in themselves, and in their relation with those exhibited
by the spontaneous appearances and disappearances of the
electric fluid; especially in the great phaenomenon of lightning
and thunder. Mr. Hausemann, of whom I have spoken above
in anote, having had the opportunity of observing the different
91
Mr.B M. For-
ster construct-
ing a similar
apparatus,
Mr. Hause.
mann also ob-
motions of my pendulum, and persuaded -that they must have serving with
some connection with the atmospheric phenomena, has con-
structed the same i aaa with large plates, and begun regular
observations. p
' 28. I stop here on this interesting subject, having, I think,
recalled it sufficiently to show, that Dr. Maycock had not
embraced, or considered with attention, all the branches of ex-
perimental philosophy connected with the determination of the
nature and functions of a fluid influencing almost all the atmo-
spheric phenomena. But in a future paper I shall treat of
another part of the same subject, by coming to the idea Dr.
Mayceck bas conceived of the effect of friction, to produce
electrical
one.
The going of
atime-piece af- |
fected by at-
traction.
A six-weeks
astronomical
slock,
EFFECT OF ATTRACTION ON THE GOING OF CLOCKS.
electrical effects ; which will give me an opportunity of examin-
ing his system under a different point of yiew.
T have the honour to be,
Sir,
Your obedient, humble Servant,
J. A. DE LUG.
Windsor, August the 27th, 1812.
Il. _
Effect of the Attraction between the Weights and the Pendulum
on the geing of Clocks. In a Letter from Mr, Tromas
REID.
Yo W. Nicholson, Esq.
Edinlurgh, 18th Aug. 1812.
SIR,
F Jate, having been much engaged with astronomical
clocks, which require a great deal of attention, to see that
they are fit to perform, and to keep as near to time as it is possi-
ble from the nature of things to bring them; it will perhaps be
thought strange to say, that attraction comes in for a share in
those obstacles, which stand in the way of good timekeeping.
This is what has never been even hinted at before; if it has, E
confess it is new tome. We have heard of clock pendulums
disturbing one another, where clocks were set agoing on the
same board, and where the pendulums were not sufficiently
fixed, but this arose from a very different cause. ;
Having fitted up a clock in every respect particularly good,
and unexceptionable both in the plan and the execution of it;
which, by express order, was made to go about one month or
six weeks, the scapement of it made after the principle sug
gested by Mudge as far back as the year 1763, and which he
afterwards introduced or used in his timekeepers. This clock,
from the nature of the scapement, and from that of its pivots
being so independent of oil, at almost all of the holes, was,
from these circumstances, expected to keep the arc of the vibra-
tion of the pendulum as nearly constant as possible ; but after
keeping
EFFECT OF ATTRACTION ON THE GOING OF CLOCKS. 03
keeping this arc perfectly for above two weeks, it surprised me,
and even mortified me not a little, to find no constancy in the Began to dimi-
: : k nish its arc of
are even here, notwithstanding very sanguine hopes had been Jip-ation in
entertained of it. One morning it was observed to have come three weeks,
‘in a little, which afterward it did gradually more and more for
some time, from a maximum toa minimum, and vice versa, and after a
until it had regained its original extent of arc, which it kept on, pe oat
till the same circumstances came again in the way to disturb it. ri
Although I saw this, and was in some degree convinced, that
this must be owing to the attraction of the weight for the pen- ‘This presumed
dulum ; yet I would not rest altogether satisfied without again to atise from
eds 2 i . , the weight at-
examining the clock, lest something might be there, which tracting the
tended to give rise to this inequality of the are of the pendu- pendulum,
lum’s vibration. But on examination, there was evidently no
cause, that could in the smallest degree be suspected, for this.
In constructing the clock, attraction was suggested by avery
: : : : i ‘ This had beew
ingenious friend, on an idea taken from the experiments that foteaean ands
had been made by Mr, Cavendish: and accordingly the barrel guarded |
was so contrived, as to throw the weight, when it came as low scape m
down. as the pendulum ball, the farthest then possible from it. ;
The weight is about 27!b. ; and the pendulum, which is a mer-
curial one, has about 10lb. of mercury in a glass jar or hollow
eylinder. In order to be more convinced in this matter, the
clock was again wound up, and during the time of the first ten
days or a fortnight it kept the arc of vibration constantly the
game, and its rate of time was somewhat less than +0°1”
per diem; when the weight had got down, and partly opposite
to the cylinder of mercury, the are of vibration began to come
in, and the clock gained in the mean time from less to more,
even to five seconds in one of those days ; when the weight had
got below the pendulum or cylinder of mercury, the former
arc of vibration was regained, and its rate of time also. The
full extent of the arc of vibration is about one degree eleven
minutes on each side the point of ‘rest, of this it lost about six
‘minutes when at its least extent.
_ There was another clock observed, which goes a month, has Another clock
somewhat of the common scapement to it, and a compensation usa Doe iy
pendulum of Ward's form, which I think is a very excellent‘ner.
one. The are of vibration is about three degrees six minutes
on each side the point of rest, the weight of the pendulum ball
about
\
O4
Month clocks
frequently
troublesome,
even stopping,
fram this
cause.
f
REFECT OF ATTRACTION ON THE GOING OF CLOCKS.
about 12Ib., and that of the going weight 281b. From the forci«
ble swing or motion of this pendulum, it was thotight, that
attraction would scarcely have any influence here; however,
the weight, when opposite to the pefdulum ball, brought the
arc of vibration gradually in to three degrees ; but on the weight
leaving or getting below the pendulum ball, the former are of
three degrees six minutes was regained.
There are few clock-makers,' who may not in the course of
their experience have had a great deal of trouble with old
month clocks, much vexation and running after them, on
account of their stopping ; and this apparently from causes inex-
plicable and undiscoverable ; and with the greatest difficulty,’
after taking them into their hands, could they sometimes be
made to go. Clock-makers, who may know the principles of
their business tolerably well, and who would find no difficulty
in making a common eight-day clock to go and perform its
office easily, have often been much put to it by month clocks.
They in general have very heavy weights, perhaps thjrty pounds
to the going part, and more than that to the striking part; the
pendulum balls are very light, litthe more than one pound
weight, if even this, and withal have very short arcs of vibra-
tion. These circumstances lead me to suspect, that attraction
had had a great hand in the stopping of these clocks ; and had
this been known then, we should have found the stopping
generally to have taken place about the time when the weights
had got down, and nearly opposite to the pendulum ball; which
is fully confirmed by my examining some old and welleexpe-
rienced clock-makers on this part of. the subject, who said, that
this actually was the case, that they always suspected among
other causes of stopping, that the weights might have touched
the pendulum, and this they very frequently examined, to see if
theie was sufficient freedom for the weights to pass the pendu-
lum ball without touching it, never dreaming of such a thing
as attraction being there ; but this of the weights being oppo-
site to the pendulum would not be much noticed,’ from no sus:
‘picion being attached to them, but that of merely touching the
Thirty hour
clocks have
advantages
over others.
pendulum ball. If the influence of attraction (which now
must be admitted) takes place in those clocks which have heavy
weights, it must take place, though in a less degree, in those
clocks which go eight days; and, were it not for the trouble of
daily
ON THE APPARENT FIGURE OF STARS.
ten)
Or
daily winding up, a thirty-hour clock would, on this account of
attraction, as well as for many other good reasons, be the most
preferable of any.
Iam, Sir,
Your most obedient Servant,
T. REID.
Til.
‘An Essay on the apparent Figure of Stars and luminous Ol-
Jjevts, seen at a very great Distance, and under a very small
Diameter. By Mr. J. H. Hassenrratz*.
lf N the year 1806, I laid before the physical and mathematical ee of
4 " vision t
class of the Institute several observations on the phenomena .nan jaar ;
of vision through small apertures ; and from them I have ex- tures.
tracted the following, on the apparent figure of stars, which
are here brought together in one paper.
If we look with the naked eye at a very remote Iumi- Luminous
nalaciuimet:: } 1 dl opis objects seen at
object; a star, aplanet, atorch, a candle, or even 4 4 distance,
house on fire ; we perceive, that these bodies are surrounded
with rays of light, having particular directions ; and that these
rays prevent our distinguishing and ascertaining the figure of
the object.
The number of these rays differs to different eyes: but two omg ee from
« : . them difier to
rays; AB, AC, pl. II, fig. 1, in the direction of the eyes, are gigerent eyes.
pretty generally observed ; as also a third, AD, perpendicular to
them. Some distinguish a fourth ray, AE, which is a prolon-
gation ef AD: others see a fifth, AF, fig.2: and in certain
circumstances the spectator observes six or eight, fig. 3.
When the luminous body is sonear the spectator, that he can The com-
approach it, he may see this phenomenon commence and in- ™<ncement |
and progress
crease, of this phzno-
On receding from a candle to the distance of distinct vision, 5 ae de-
scribed.
its figure is commonly that of a spear head, fig. 4. On receding
* Ann, de Chim, vol. xxii, p.,§.
; | farther,.
96
Luminous ob-
jects seen
througha
transparent
substance.
Star seen
through a te-
lescope.
ON THE APPARENT FIGURE OF STARS.
farther, its dimensions are changed, and the flame appears
broader, as at fig. 5. Lastly, on retiring still farther, it assumes
the figure of a lozenge, as at fig. 6; and at a greater distance it
begins to exhibit cross rays.
The distance at which these cross rays begin to appear, is
different with different people. Ihave always observed them,
when I was twenty-five or thirty yards from a candle, and when
consequently its flame was seen under an angle of one or two
minutes, Some distinguish these rays at ashorter distance ;
others do not begia tu perceive them till they are much farther
off*,
The length of the rays issuing from the stars is so much the
greater, in proportion to their brightness, and to the darkness
of the night. The luminous rays of candles, torches, and
bodies on fire, diminish in length in proportion to the intensity
of their light ; but we see those of thestars increase from the
time of twilight, when they begin to be perceptible, to the
time when the night is very dark.
If we iook through a body of clear water, or any transparent
substance, at a star or bright light, that would appear to give
out long luminous rays to the naked eye; we shall perceive,
that the length of their rays diminishes, in proportion as the
thickness of the body of water, or transparent substance,
through which they are seen, is increased.
A star seen through a telescope, the object glass of which,
being of large diameter, increases considerably the intensity of
the light at its focus, appears to be accompanied with four or
more luminous rays. But if the intensity of the light be di-
minished, eitber by lessening the diameter of the object glass,
intercepting a part of its light, enlarging the surface of the
image, or any other method, we find the length of the rays
gradually diminish, till, the intensity of the light not being suf-
ficiently great, the rays cease to be perceptible ; and then the
* Is notthis appearance of luminous objects seen at a distance, the
origin of the figure under which stars are generally represented,
though we have every reason to believe, that their form is spheroidal ?
Is it not their different appearance to different eyes, that has given rise
to their being represented with a different number of rays? And is it
not because most people perceive five rays, that they are usually deli-
neated with this number ?
star
ON THE APPARENT FIGURE OF STARS. 97
star has the appearance of a circular disk, surrounded by a coe
loured aureola.
The coloured aureola, that accompanies the circular image of Coloured au-
the stars, when their light is too weak for the rays to be per- oo ake
ceived, is independent of the cause that produces this latter
phenomenon. It appears to be occasioned by the object glass
being more or less imperfectly achromatic ; by the faintness of
the image, which permits the aureola to be distinguished ; by
the inflection of the ray of light at the edges ofthe diaphragm,
that lessens the object glass; and by several other causes, on
which I shall not attempt to enlarge in this paper.
As the rays that accompany luminous bodies are not per- Disc of a pla-
ceived, unless the object producing them be seen under a very ®¢t Magnified.
small angle, it follows, that when the diameter of a planet is
increased by the assistance of a telescope, so as to be seen under
an angle of some minutes, the rays disappear, and the planet is
clear and well defined.
In these rays there is this particularity, that their direction ps ection
always depends on that of the eyes looking at the object. the rays de-
Thus, if, when looking at a distant light, we incline the head, shape Gn tie
as at fig. 7, we shall immediatély perceive the direction of the
rays change. One of these directions is constantly parallel with
the two eyes, moving with them; and the others preserve their
relative situation with respect to this.
The rays distinguished round luminous objects may be pro- The rays pro-
duced, either by the luminous body itself, or by the organ that duced by the
is aa Visual organ,
discerns them. In the first case, the number and position of
the rays should be the same to every spectator : but, as the
number of these rays varies to different eyes, and follows thé
direction of the eyes when these are inclined in looking at the
object, it follows, that the rays are produced by the organ per-
ceiving them. Y
This truth is farther confirmed by looking at stellate lights They are de-
stroyed by
through a small aperture ; as this immediately destroys the rays, ;° jane
and the luminous bodies appear of smaller dimensions. In this through a
case their figure is altered only by the inflection of the light 8m! hole.
at the edges of the small aperture ; an inflection which gene-
rates aureola round the images of luminous objects.
Since the rays, that appear to emanate from luminous objects How does the
seen at a great distance, are produced by the eye that perceives eye produce
Vou. XXXIII, No. 152.—Ocrozer, 1812. H them;
98 ON THE APPARENT FIGURE OF STARS.
this appear- them ; it remains to ascertain, for the explanation of the phz-
sere nomenon, how this appearance may be produced, and what
part or parts of the organ produce it.
Rays caused The lachrymal fluid, by which the cornea is constantly co-
Oe Y- vered, gives rise to the perception of several rays, when, in
of a different winking the eyes, the two lids approach the iris: but these rays
— are essentially different from those here considered, to which
the namie of irradiation has been given. ‘The rays produced by
the lachrymal fluid are all perpendicular to the direction of the
eye-lids, and are produced only when these are brought very
near together. They are seen sometimes at top only, some-
times at bottom, sometimes both at once, ; and this according
to the position of the eye-lids with respect to the iris: and
they are perceived at all distances from the luminous object.
Irradiation, onthe contrary, is discerned only when the light is
at a very great distance, and seen under a very small angle.
The separation of the eye-lids has no influence on this phzeno-
mienon : it is always perceived, however wide they are asunder :
and lastly the rays are seen in four, five, six, or eight direc-
tions, one of which is always parallel to the eye-lids,
A aici? eave As the production of this phenomenon cannot be ascribed
or aqueous or to the retina that covers the bottom of the eye, and receives the
pale hu- image ; or to the aqueous and vitreous humours, through which
; the pencil of light passes ; we have every reason to believe, that
it is owing to the action of the cornea, or of the crystalline, or
to the action of both conjointly.
Effect of the The cornea and crystalline, by the nature of the curvature of -
eornea and their surface, refract the divergent rays that arrive at the eye,
crystalline. and cause them to converge to a particular focus. Now it is
; demonstrable by analysis, and may be verified by experiment,
as I have ascertained, that if the surfaces separating mediums
be segments of a sphere, the image produced by the rays ema-
natiag from a luminous object, and received on a plane perpen-
dicular tothe axisof the pencil is always a circle: but if the
Effect of a curved surface, convex toward the least refracting medium, be
comet kt , Senerated by two different osculatory radii, the image is formed
refracting sur- of two ellipses, which intersect each other at an angle depend-
face. ing on the position of these two radii. If, therefore, the sur-
faces of the cornea, or of the crystalline, be not segments of a
sphere, this is sufficient to cause the image, formed at the bot-
tom
ON THE APPARENT FIGURE OF STARS. 99
tom of the eye by the light traversing this organ, to approach so
much the more the form of a cross, in proportion as the lumi-
nous object is more remote from the eye, and as the two radii,
generating those surfaces, differ more from each other.
The two ellipsoidal images decussating each other, fig. 8, are Ellipsoidal
constantly seen, if a ray of solar light, the light of a candle at /°™*
a distance, &c. be made to pass through an ellipsoidal Jens.
The same image, too, is observable, if they pass through irregu-
lar surfaces ; such, for instance, as phials or decanters filled with
water, &c.
It is extremely difficult to ascertain with precision the figure Figure of the
of the surface of the cornea in the living subject. After death aig at
the cornea becornes flaccid, and undergoes alterations that pre- to ascertain.
vent us from distinguishing accurately the natare of the sur-
face it had. Attempts were made to ascertain the figure of the
eye by freezing it: but the increase of bulk of the fluid by
congelation so altered it, that it was impossible to form a precise
idea of the nature of its curved surface.
On looking at a fresh human cornea, it appears to be of an Apparent irre-
irregular figure, but this irregularity is occasioned, in great Ce rmabgient
measure, by the projection of the tunica conjunctiva over the
upper part of the cornea. Dr. Petit, who paid great attention Petit’s opi-
to the figure and dimensions of the eye, says, in a paper pub- ™°™
lished among those of the Academy of Sciences, in 1726, that,
when the portion of the conjunctive coat advancing upon the
cornea is dissected off, the latter is commonly round: yet he
met with the cornea of a negro, that measured 5 ‘5 lines French
from right to left, and only four from top te bottom. I have
found it hitherto impossible, to obtain accurate data; all my Probably, iat
observations, however, lead me to believe, that it is not sphe- spherical.
rical,
As the crystalline may easily be separated from the eye, The rystal-
physiologists could not fail to make observations on it. Accord- line.
ingly, all who have treated on the organ of sight have been
ready to describe the figure and composition of the crystalline.
Galen considers the crystalline as not being a perfect sphere, Different ac-
uniform throughout its whole extent ; but approaching toa com- panna: of its
pressed globe, fig. 9.
Rufus of Ephesus thinks, that from its figure it should be
ealled lenticular.
H2 | The-
100 ON THE APPARENT FIGURE OF STARS.
Theophilus asserts, that the interior surface of the crystal.
line is less convex than the exterior: fig.10, Fallopius, Zinn,
and many other anatomists, are of the same opinion.
Vassalli says, he has observed the convexity equal on both
surfaces : fig. 11. :
Brisseau asserts, that the surface of the crystalline next the
cornea is more convex, than that which is in contact with the
vitreous humour.
Petit, who had seen and observed a great number of crystal-
lines, says he observed some to have the anterior curvature
greater than the posterior, fig. 12; but that most commonly
the side toward the cornea had a radius of curvature greater
than that in contact with the vitreous humour, fig. 10. He
says even, that he found in several subjects the crystallines to
have their greatest curvature, one at the anterior surface, the
other at the posterior ; and that he has met with crystallines
both surfaces of which were equal, fig. 11.
Those anatomists agree in considering the two surfaces of
the crystalline as two segments of a sphere applied to each
other, fig. 13.
Dr. Thomas Young concludes from observations made on
his own eyes, that the anterior surface of the crystalline must
be a portion of an hyperboloid, and the posterior surface a por-
tion of a paraboloid: but he admits, that his experiments
would not succeed equally with every eye.
Dr. Petit says, he has met with crystallines, the posterior
convexity of which was not spherical, but approached the para-
boloid form.
Itsfigurevaries All persons, who have made observations on crystallines,
with age. know that their figure varies with age. Those of infants are
small and thick. Insome fcetuses the thickness is but little
less than the breadth. Those of adults are about twice as
broad as they are thick. Those of old men grow flatter and
yellow.
Its dimensions. Petit bas observed, that the dimensions of the crystalline are
not always proportional to the age ; and though in general the
breadth is 9 mil. [3 54 lines],and the thickness 4°5 [1°77 lines],
he has found it from 5 to 8-thick [1°97 to 3'151.], and even 9
[3°54l). |
Thug,
ON THE APPARENT FIGURE OF STARS. 101
Thus, there is not only a want of agreement between anato- It differs great-
mists respecting the figure of thecrystalline ; but they who have ly,
observed it with the greatest care, as Petit, find very great
differences in it ; differences that must necessarily affect vision,
and produce in great measure those variations, which have been
noticed in the sight of different persons by physiologists and
natural philosphers.
Whatever care has been taken to ascertain the figure of the Its anteriorand
crystalline, observers hitherto appear to have attempted only Ea uae
to determine the proportions that exist between the versed sines to unite in a
of the curvature of the segments, AB, AC, fig. 14, and the circular line,
length of their chord, DE. No one that I know has endea-
voured to ascertain, whether the plane of the posterior and
anterior segments were circular; and whether there existed
any difference between its diameter from right to left DE, and
its height GF. This difference appeared tothem not suffi-
ciently perceptible to be measured.
However, as there are some crystallines, the horizontal and This not al-
vertical diameters of which exhibit a pretty considerable "”°¥* jee re
difference, these could not escape an accurate observer. ‘Thus Petit.
Petit, in a paper read to the Royal Academy of Sciences in
173Q, says: ‘* the circumference of the crystalline is commonly
round ; yet I have found some in the human subject, that were
not so, and the diameter of which was a quarter of a line
longer one way than the other.”
In this paper Petit describes a great number of observations He examined
made on the crystallines of various animals; those of man being !¢ 19 various
introduced only as forming one of the links of the great chain. aa
As Petit is the only person, who has measured crystallines The examina-
with sufficient care to perceive, that those of man are not tion repeated.
round ; and to observe, that one of the diameters exceeded the
other by a quarter of a line; I thought it might not be amiss
to repeat these experiments, in order to satisfy myself whether
this particular observation of Petit was sufficiently general, to
contribute to the production of the irradiation; and at the
same time ascertain the directions in which the longer and
shorter diameter are placed.
I immediately procured two sheep’s eyes, which I opened Sheep’s eyes.
cautiously. On taking out the crystallines, and laying them
flat, I perceived, that the curve uniting the two segments was
longer in one direction than in the other.
102 ON THE APPARENT FIGURE OF STARS,
The author as- Having no human eyes at my disposal, I requested Dr. Chaus-
tae Dr. sier, professor at the School of Physic, to assist me with the
> means of ascertaining, whether the curve of the human crys-
talline, seen in front, was constantly a circle, as is commonly
supposed. This gentleman complied with my wishes; and
had the goodness, not only to procure me the eyes necessary
for my researches, but to assist me with his skill and advice.
and Mr Ribes. Mr. Ribes, at that time assistant dissector to the school,
brought us eyes of foetuses, adults, and old men. To these
we added eyes of sheep and oxen*, in order to compare their
dimensions.
Widde we per- Mr. Ribes opened some of the eyes, cutting them trans-
forming the versely ; and took out the crystallines with sufficient caution,
experiments, to ascertain the place that each part occupied in the eye. Dr.
Chaussier likewise opened some eyes by the operation for the
cataract. He took out the crystallines, retaining precise marks
of their situation. These crystallines laid flat had all an oval
form. I measured with a pair of compasses the vertical dia-
meter CD, and the horizontal AB, fig. 15, and constantly found
the former greater than the latter.
‘Thecrystalline The crystalline is a kind of oblate spheroid. I call the hori-
described. zontal diameter, fig. 15, the length AB, which is in the direc-
tion of the eye-lids ; the vertical diameter, the height CD,
which is perpendicular to it; and the less diameter, the thick-
ness EF of the two segments.
After each operation, Dr. Chaussier dipped the ctystallines
in sulphuric acid, diluted with water, in order to harden them,
and free them from the membrane that envelopes them. After
Méasured a- this we measured them anew ; and constantly found, that the
cae a curve of intersection between the two segments was elongated
removed. in the direction of its height.
Dimensions of Inthe two crystallines of a foetus the vertical diameter CD
peach was 8 mil. [3°147/.], and the horizontal AB 7°75m. [3°049/.].
The vertical! diameter of one of the ae of an adult was
11 m, [4°328/.], and the horizontal 10°25 m. [4°033/.]. The
second was not measured, because in taking it out the position
of each part in the eye was forgotten to be marked. The two
* It appears from what follows, that they were the eyes of one fetus,
two adults, one old man, one sheep, and one of only.
crystalline
ON THE APPARENT FIGURE OF STARS. 103
crystallines of a man of forty had their vertical diameter 10m.
(3°934/.], and their horizontal diameter 9°6m. [3°777/.]. The
yellow crystalline of an old man had a vertical diameter of
9°25m [3°630/.], and a horizontal diameter of 8°75m.
[3:442/]. The second crystalline was not measured, because
it appeared to have had its shape altered.
The two crystallines of an ox had a vertical diameter of Those of the
19'15m. [7°534].], and a horizontal diameter of 18°75m., ° 4nd sheep.
[7°3771.]. That of a sheep had a vertical diameter of 17°35 m.
[6°826].], and a horizontal diameter of 17 m. [6 688].].
These observations, made by Dr. Chaussier, Mr. Ribes, and
myself, prove, that in the human crystalline the vertical axis
is longer than the horizontal ; and, consequently, that the two The surfaces
Surfaces, the anterior and posterior, are generated by different a oe
curves, among which those that are vertical have a greater
radius of curvature than those that are horizontal.
The curve of several of these crystallines appeared to us a and apparent-
little irregular. The diameter measured in various directions beret ine
seemed to be different from those an ellipsis should have had ; we”
but the differences were not considerable enough to be deter-
mined accurately with the compasses which we used for measur-
ing the diameters:
Since the curve formed by the planes of the anterior and The crystal-
posterior segments of the crystalline is not a circle, it follows, Pe
that their surfaces are not spherical; and hence, that the rays ence eae
of light passing through them must have as many different
foci, as we can conceive osculatory radii to have been em-
ployed in generating their surfaces. Thus the crystalline alone,
from the irregularity of its surfaces, is capable of producing ‘
wholly, or in part, those irradiations, which are perceived on
looking at very remote lights.
The surface of the cornea too, appearing not to be an exact but the cornea
segment of asphere, must contribute to the production of new Sosa pi
foci, whence arise new irradiations. Thus every thing appa- non,
rently concurs to refer the production of the irradiations per-
ceived from remote luminous objects seen under a very small
angle to the combined actions of the crystalline and cornea, that
is, to the nature of their curved surfaces.
From the facts here recited it follows :
1. That the figure of luminous objects within the sphere of General con-
distinct vision is perfectly distinguishable. 2. That ¢lusions.
104 DOUBLE REFRACTION OF CRYSTALS.
2. That these figures are altered, in proportion as we recede
from this ; and that at a great distance, when these objects are
seen under an angle of one or two minutes, they appear sur-
rounded with several irradiations, two of which are in the
direction of the eye-lids.
3. That these irradiations are independent of the figure of
the luminous object, and are produced by the organ perceiving
them.
4, That these irradiations are occasioned chiefly by the
irregular figure of the surfaces of the crystalline and cornea.
5. Lastly, that this irradiation is not well distinguished,
except in the dark; because, the iris having then a greater
opening, the irradiation occasioned by the irregularity of the
surfaces of the crystalline and cornea becomes more percep-
tible.
IV.
On the double Refraction of Light in transparent Crystals: by
Mr. Lariace.*
Refraction of IGHT, when it passes from the air iato a transparent me~
lake. dium not crystallized, is refracted so that the lines of inci-
dence and refraction are constantly in the same ratio: but in pass-
ing through most diaphanous crystals it exhibits a singular phze-
nomenon, which was first observed in Iceland crystal, where it
ig very perceptible.
Double refrace 4 Yay of light, falling perpendicularly on one of the natural
tion, faces of this crystal, divides into two parts; one traversing the
crystal without altering its direction; the other deviating from
it in a plane perpendicular to that face, and passing through the
axis of the crystal, that is, through the line that unites the sum-
mits of its two obtuse solid angles. This division of the ray
generally takes place with regard to any face, natural or artifi-
cial, and whatever be the angle of incidence; one portion fol
lowing the law of common refraction, the other a law of extra-
Law of the ex- ordinary refraction first discovered by Huygens; and which,
traordinary re- considered as the result of experiment, may be classed among
fraction disco-
vered by Huye ,
gens, 3 * Journal des Mines, vol, XXIV, p. 401.
the
DOUBLE REFRACTION OF CRYSTALS. 105
the finest discoveries of that eminent genius. He was led to it
by the idea he had formed of the propagation of light, which His rape
he supposed to be produced by the undalations of an ethereal oe of light.
fluid. According to him, the velocity of these undulations was
less in common transparent mediums, than in a'vacuum, and
the same in all directions. But he supposed there were two
kinds of undulations in Iceland crystal: and that the velocity of
one was the same in all directions, as in ordinary mediums ;
but that the velocity of the other was variable, and repre-
sented by the radii of an oblate ellipsoid of revolution, the
centre of which was at the point of incidence of the lumi-
nous ray on the face of the crystal, and the axis parallel to the
axis of the crystal. Huygens had also found, that, to render
the hypothesis answerable to experiment, the velocity of the
undulations respecting the ‘ordinary refraction must be repre-
sented by half the conjugate axis of the ellipsoid; which con-
nects in a very remarkable manner the two refractions, the or-
dinary and extraordinary. This great geometrician did not
assign the cause of this variety of the undulatioiis; and the
singular phenomenon exhibited by the light in passing from
one crystal to another, which will be noticed at the end of this
paper, is inexplicable on his hypothesis. This, added to the His law re-
great difficulties offered by the theory of waves of light, occa- Jected :
-sioned Newton, and most of the philosophers who have fol-
lowed him, to reject the law of refraction, that Huygeris had
attached to it. But Mr. Malus having proved the precision of but Malus has
this law by a number of very accurate experiments, we should alt ie
separate it altogether from the hypothesis that led to its disco-
very*. It would be very interesting to connect it, as Newton. .
has done ordinary refraction, with the attractive or repulsive
forces, the action of which is sensible only at imperceptible
distances. It is, in fact, very probable, that it depends on them; The result of
and I have satisfied myself of it by the following ponsidernbenes ptbrectian:
The principle of a minimum of action generally takes place Principle of
in the motion of a point subjected to forces of this kind. On least action ap
applying this principle to light, we may set aside the imper- piodte Gah.
* Dr. Wollaston had before shown the hypothesis of Huygens to be
agreeable to experience: See Phil. Trans, for 1802, or Journal, vol.
IV, p. 148. C.
ceptible
106
DOUBLE REFRACTION OF CRYSTALS.
ceptible curve it describes in its passage from a vacuum into a
transparent medium, and consider its velocity as constant,
when it has entered into it by a perceptible quantity. The
principle of a minimum of action then is reduced to this, that
the light arrives from a point without the crystal toa point
within it, in such a manner, that, if we add the product of the
right line it deseribes without multiplied by its primitive velo~
city, to the product of the right line it describes within
multiplied by its corresponding velocity, the sum will
be a minimum. This principle always gives the velocity
of light in a transparent medium, when the law of refrac-
tion is known: and reciprocally it gives this law, when the
Case of extra. Velocity is known. But a condition to be fulfilled in the case
Ordinary re-
fracticn,
\
Law of Huy-
gens,
Expression of
the velocity.
of extraordinary refraction is, that the velocity of the luminous
ray in the crystal shall be independent of the manner in which
it entered, and depend only on its position with respect to the
axis of the crystal, that is, on the angle which it forms with a
line parallel to the axis. In fact, if we imagine an artificial
face perpendicular to the axis, all the interior extraordinary
rays, that are equally inclined to this axis, will be so likewise
to the face, and will evidently be subjected to the same laws at -
issuing from the crystal: all will resume their primitive velo-
city in the vacuum; the velocity in the interior therefore is the
same for all. I have found, that the law of extraordinary re-
fraction given by Huygens fulfils this condition, as well as it
does that of the principle of a minimum of action; which
leaves no room to doubt, that it is owing to attractive and
repulsive forces, the action of which is sensible only at imper-
ceptible distances. Hitherto it could only be considered as
approaching it within limits less than the inevitable errours of
experiment: now it may be taken as a precise law. .
A valuable datum for the discovery of the nature. of the
forces that produce it is the expression of the velocity, to which
analysis has conducted me; and which I find equal toa frac-
tion, the numerator of which is unity, and the denominator of
which is the radius of the preceding ellipsoid, according to
which the light is directed, the velocity in vacuo being taken as
unity. Ishow, that the velocity of the ordinary ray is unity
divided by the semiaxis of revolution of the ellipsoid; and by
these
DOUBLE REFRACTION OF CRYSTALS. 107
these means the very remarkable connexion, that Huygens
found by experiment, between the ordinary and extraor-
dinary refractions of the crystal, is demonstrated a@ priori,
as a necessaty result of the law of extraordinary refraction,
The velocity of the ordinary ray in the crystal therefore is Difference of
always greater than that of the extraordinary ray, the difference Ve oe
of the squares of the two velocities being proportional to the rays,
square of the sine of the angle that the axis forms with the
latter ray.“ According to Huygens, the velocity of the extra-
ordinary ray in the crystal is expressed by the radius of the
ellipsoid itself; his hypothesis therefore is conformable to the
principle of least action: but it is remarkable, that it is also con-
formable to the principle of Fermat, which consists in this, Principle of
that the light arrives from a given point without the crystal (o Fermat.
a point within in the shortest time possible; for it is easy to
see, that this principle is reduced to that of the least action, by
reversing the expression of the velecity. Thus the law of
refraction given by Huygens is deducible equally from both of
these principles. For the rest, this identity of the laws of
refraction, deduced from the mode in which Huygens viewed
the refraction of light, with those given by the principle of
least action, takes place generally, whatever be the spheroid,
the radii of which, according to him, express the velocity of the
light in the interior of the crystal. This I demonstrate very
simply in the following manner.
Huygens considers a ray RC, pl. II, fig. 16, falling on the ANE Poryes
natural or artificial face A F E K of an Iceland crystal. Draw- of Huygens.
ing a plane, CO, perpendicular to this ray, and taking OK,
parallel to C R, to represent the velocity of light in vacuo, he
supposes, that all the points Coo0'O of the luminous wave ar-
rive in the same time, and in parallel directions, at the plane
Kii1l; which he finds thus. A FED isan ellipsoid of revo-
lution, of which C is the centre, C D the semiaxis of revolu-
tion ; and the radii of which represent, according to Huygens,
the respective velocities of the light that follows their direc-
tions. Through the ray RC he draws a plane perpendicular
to the face, and cutting it in the right line BC K; and through
the point K he draws, in the plane of the face, K T, perpen-
dicular to K C. Lastly, through K T hé draws a plane K I,
touching the ellipsoid in I. According to him C I is the direc-
tion
108 DOUBLE REFRACTION OF GRYSTALS.
tion of the refracted ray. In fact it is easy to show, that in
this construction any given point o of the luminous wave
arrives at 7, through the broken line ocz, in the same time as O
arrives at K. CI representing the velocity of the refiacted
ray, the right line CI is traversed in the same time as the
right line OK. Let us take this for the unit of time, and O K
for the unit of space. The point o arrives at cin a time pro-
! Ce
portionate to oc, and consequently equal to ae It passes from
c toZ in the interior of the crystal, in a time equal to that
which the light employs in passing from C to I multiplied by
Ba aiid consequently equal to Bees being parallel to CI.
CK KC
By adding this time to = we shall have unity for the time
that the point o employs in arriving atz.
Let us take o c’ infinitely near too c, and parallel to it, the —
point o will arrive at 2 in the unit of time. Draw the right
lines co and c i, and suppose, that the pout 0 proceeds to z
through the broken line oc’ i. Nowc o being perpendicular
to C O, the right line co may be supposed equal to co, and
the times required to pass through them may be supposed equal.
Moreover, the time required to pass through cz may be sup-
posed equal to the time required to pass through c’ 7’, because,
the plane K I touching inz the spheroid similar to the spheroid
A FED, the centre of which is inc, and the dimensions of
which are diminished in the ratio of K c’ toK C, the two
points z and 7’ may be supposed in the surface of the spheroid.
According to Huygens the velocities according toc 2and cz
are proportional to these lines; the times employed in passing
through them therefore are equal. Thus the time cf the
transmission of the light in the broken line o c’i is equal to
unity, as in the broken line o cz: the differential of these two
times therefore is null, which is the principle of Fermat.
a ee it is clear, that this reasoning is generally applicable, what
any spheroid, ©Vet be the nature of the spheroid, and the position of the
points c and c’ on the face of the crystal; even if they be not
in the right line CK, provided they be infinitely, near it.
The hypo- Reversing the expression of the velocity, thé principle
theses of Huy-
gens, chonaé, “of Fermat gives that of the least action. The laws of refrac+
false, repre- tion arising from the hypotheses of Huygens, therefore, are
sent the fact,
generally
DOUBLE REFRACTION OF CRYSTALS. 109
generally conformable to this latter principle ; and for this rea-
son these hypotheses, though erroneous, represent the fact.
If we put =the semiaxis of revolution of the ellipsoid of
Huygens, a= its semitransverse axis, o= the velocity of a
ray of light in the interior of the crystal, and = the angle its
direction makes with the axis, the radius of the elipsoid will be
ab
, “a*—(a®—b?). sin*. V. Thus the velocity v, from the
principle of least action, being equal to unity divided by this ra-
dius, we shall have v°=5;— (i): Ca il
This velocity is least when the ray of light is perpendicular
to the axis of the crystal, and then it becomes +: it is least,
when it is parallel to this axis, and then it is equal to >.
Huygens found by experiment, that 0 is the ratio of the sine Connexion be-
of refraction to the sine of incidence in the common refraction si A ke
of the Iceland crystal. This very remarkable result, which ;
connects the ordinary and extraordinary refractions, is ‘a neces-
sary consequence of the modifications that distinguish the ordi-
nary from the extraordinary ray not being absolute, but solely
relative to the position of the ray with respect to the axis of the
crystal. To show this, let us refer to the singular phenome-
non, that light exhibits after its passage through a crystal.
In passing through a crystal) the light is divided into two pen- area -
cils, one ordinary, the other extraordinary, and each of them Rascsine Gs
issues out of the crystal undivided, If we conceive a second througha
crystal placed beneath the first, in a situation perfectly similar, ae
the ordinary ray will be refracted ordinarily on passing into the
second crystal, and the extraordinary ray will be refracted extra-
ordinarily. This will take place generally, if the principal
sections of the two opposite faces be parallel. By theprincipal
section of a face is meant a section of the crystal by a plane
perpendicular to that face, and passing through the axis of the
crystal. But, if the principal sections be perpendicular to each
other, the ordinary ray will be refracted extraordinarily on pas-
sing into the second crystal, and the extraordinary ray will be
refracted ordinarily. Inthe intermediate positions, each ray
will be divided into two others at its entrance into the second
crystal.
Now suppose a ray refracted ordinarily by one crystal to fall
per-
110 DOUBLE REFRACTION OF CRYSTALS.
perpendicularly on a second crystal cut by a plane perpendicu-
lar toits axis: it is clear, that an infinitely small inclination of
the axis to the face of incidence will be sufficient to change this
ray into an extraordinary ray. Bat this inclination can pro-
duce but an infinitely small change in the action of the crystal,
and consequently in the velocity of the ray within it: this velo-
city, then, is that of the extraordinary ray, and consequently it
is equal to +: which comes to the same as the result of Huy-
gens : for itis Known, that the velocity of light, in common
transparent mediums, expresses the ratio of the sines of inci-
dence and refraetion, its velocity in vacuo being taken as unity.
Reflection of The principle of least action may serve also to determine the
light. laws of the reflection of light; for, though the nature of the
force, that causes light to rebound from the surfaces of bodies,
is unknown, it may be considered as a repulsive force, which
restores, ina direction contrary to that of the light, the velocity
it causes it to lose; as elasticity restores to bodies in a contrary
direction, the velocity which it destroys. Now we know, that,
in this case, the principle of least action always subsists. With
respect to a luminous ray, whether ordinary or extraordinary,
reflected by the exterior surface of a body, the principle is re
duced to this, that the light passes from one point to another by ~
the shortest path of all those that fall in with the surface. In
fact, the velocity of reflected light is the same as that of direct
light : and it may be laid down as a general principle, that,
when a ray of light, after having experienced the action of as
many forces as you please, returns into a vacuum, it resumes its
original velocity. The condition of the shortest path gives the
equality of the angles of reflection and incidence in a plane
perpendicular to the surface, as Ptolemy had already remarked.
It is the general law of reflection at the external surfaces of
bodies.
Reflection in But when light, on entering intoa crystal, is divided into
pea gaeaeh ordinary and extraordinary rays, one portion of these rays is re-
tion. flected by the interior surface at their exit from the crystal. In
being reflected, each ray, whether ordinary, or extraordinary,
divides into two others; so that a solar ray, penetrating the
crystal, forms. by its partial reflection at the surface of emission
four distinct pencils, the direction of which I shall proceed. to
determine.
Let
DOUBLE REFRACTION OF CRYSTALS. . 111
Let us suppose the surfaces of entrance and emission, which Case of paral-
we will call the first and second faces, to be parallel to each lel surfaces,
other. Let the thickness of the crystal be imperceptible, yet
greater than the sum of the radii of the spheres of activity of
the two faces. In this case it will be demonstrated, by the
preceding reasoning, that the four reflected pencils will form
but one perceptibly, being in the plane of incidence of the ge-
nerating ray, and forming with the first face an angle of reflec-
tion equal to the angle of incidence. Now let us restore the
crystal to its proper thickness : it is clear, that, in this case, the
reflected pencils, after issuing from the first face, will assume
directions parallel to those they had taken in the former case :
these pencils, therefore, will be parallel to each other, and to
the plane of incidence of the generating ray; only, instead of
being confounded to the senses, as in the former case, they will
be separated by distances so much the greater, as the crystal is
thicker.
_ Now, if we consider any given interior ray issuing out in
part by the second face, and in part refiected by it into two pen-
cils, the issuing ray will be parallel to. the generating ray ; for
the light, as it issues out of the crystal, must take a direction
parallel to that it had on entering into it; since, the faces of
entrance and exit being supposed parallel, itis acted on at its
exit by the same forces as it, was at its entrance, but in the op-
posite direction. In the direction of the issuing ray, let us
conceive a plane perpendicular to the second face ; and in this
plane Jet us imaginea right line, exterior tothe crystal, passing
through the point of exit, and forming with the perpendicular
to the face, but on the side opposite to the direction of the is-
suing ray, the same angle as that direction ; lastly, let us con-
ceive a ray of light entering the crystal according to this right
line. This ray, at its entrance, will be divided into two others,
which, at issuing out of the crystal by the first face, will take
directions parallel to that of the ray before its entrance by the
second face ; they will be visibly parallel to the directions of the
two reflected pencils ; which cannot take place but as far as the
two rays, into which the ray of light is divided on entering by
the second face, confound themselves respectively in the interior
of the crystal with the directions of the two reflected pencils.
But the law of Huygens gives the directions of the rays into The law of
which
112 | IMPROVED. REVLECTING CIRCLE.
Bot bate which the ray of light is divided; therefore it will give those
’ likewise of the two pencils reflected in the interiot of the erys-
tal.
and in the If the two faces of the crystal be not parallel, we shall have
ae mee by the same law the directions of the two rays, into which the
rallel. generating ray is divided in entering by the first face: we shall
have also, by this law, the direction of each of these rays at its
exit by the second face: next, the preceding construction will
give the directions, in the interior of the crystal, of the four
pencils reflected by this face : and, lastly, by the law of Huygens
we may deduce their directions at issuing out of the crystal by
the first face. Thus we shall have all the phenomena of the re-
flection of light by the surfaces of transparent crystals, Mr.
Malus first discovered these laws of the reflection of light, and
he has confirmed them by a great number of experiments. Their
agreement with the results of the principle of least action come-
pletes the demonstration of the position, that all these phzeno-
Mena are owing to the action of attractive and repulsive forces*,
V.
Description of a Reflecting Circle, in which the Screens can be
readily shifted wm taking altitudes: by Mr. J. Awan,
Blewitt’s Buildings, Fetier Lane.t
SIR,
Improved re- BEG leave to inform you, that‘on Thursday last I left at the
flecting circle, Society’s house a mathematical instrament, adapted for the
_ use of mariners, which I wish to submit to the Society’s atten-
tion. It is a reflecting circle, commonly called, La Borda’s
circle, for the purpose of taking altitudes and distances at sea ;
and which J have greatly improved lately, by fixing the shade
glasses difierent to what had heretofore been done, with some
other improvements as a reflecting circle. Thelate Dr. Mackay,
# For the two papers of Mr. Malus om this subject, see Journal,
vol. XXX, pp. 95 and 161
+ Trans. of the Soc. of Arts, Sc. vol. XXIM p. 106. The'silverme-
dal dnd twenty guincas were voted to Mr, Allan for this improvement. |
ina
IMPROVED REFLECTING CIRCLE. L138
in a publication of his, called Mackay’s Longitude, has a plate
of La Borda’s original instrument, but the shade glasses are 50 nefect in La
fixed, as to render the instrument useless, and which he was Borda's.
convinced of, on my pointing out to him the fault. He said he
would alter his plate to my method, and that he would state it
as my improvement ; but his death soon afterwards prevented
it. Iam aware the Society do not confer their rewards with-
out advantageous qualities to merit their sanction. I respect-
fully say, that I consider my instrument to have merit, both in
economy, and in the great improvement made on the plan of
the reflecting circle first invented. I shall be happy to point
out this to the Society, and have the honour to be,
Sir, your humble servant,
JAMES ALLAN,
Blewiti’s Buildings, Fetter Lane,
Dec. 24th, 1810.
SIR,
Agreeably to the intimations of the committee on Thursday Useful both to
evening last, I beg leave to explain to the Society the proper- mariners and
ties of my improved reflecting circle ; and which, witha theo- es
dolite attached to it, would be useful both to the mariner and
surveyor. '
The committee inquired what sort of centre or axis the Nitiie er eae
instrument had, I beg leave to state, it is an improved one tring.
of mine. The former way of centring this instrument. was
only by a single pin, which both indexes acted upon; but the
pin had so little bearing inthe index, that it was not sufficient
to keep the index-glass upright to the plane of the instrument
in all its positions; I have therefore contrived to put what is
called in our business a male and female centre or axis, upon
a simple but accurate method.
Permit me to make a few observations on circular instru- Horizontal
ments in general. I believe it will be universally allowed, Pret vs)
that it is easier to make a circle nearer to truth, with respect to
its horizontal plane, than it is to make a separate part of a .
circle so. |
, Asextant is only the sixth part of a circle, and is got flat jade truer
by means of a plane, as near as the maker can get it, but is than of a part.
not turned on its own axis asa circle is: therefore I have no
doubt, but that the best sextant usually made is very short of
Vou. XXXII, No, 152, Ocropgr, 1912. 5 Shae the
114 IMPROVED REFLECTING CIRCLE.
the horizontal truth of a sixth part of a circle; and if we were
to suppose a circle made of six of the usual sextants, it would
be a very untrue circle with respect to its horizontal plane.
Reflecting cir- It has, therefore, been a general desideratum, that a
eles made in circular instrament of reflection should be introduced, of simple
various ways. nS : :
construction, easy to adjust, and convenient for use. I have
been induced to-make several circular instruments of reflection
in various ways, but none upon so simple a construction, or so
cheap as the present, nor so well calculated to prove any untruth,
as my improvement upon Borda’s ; and I believe it will now
be generally adopted for use.
Borda’s unsa- There have been great numbers of Borda’s circles made ;
tisfactory. ‘TT myself assisted about twenty-five years ago to make many,
also since I have been in business for the last twelve years on
my own account, but I never found any of them to give satis-
faction till I invented the present improvement.
Captain M‘Lennan, who traded to South America, had one
of Borda’s circles made, similar to that described in Dr.
Mackay’s Longitude, but could not use it till altered by me
last April.
The improved The glasses in my instrument are movable to any quarter
ae Nia * that a person may wish to use it in; and by taking the same
proving its angle with each quarter, it affords an opportunity of proving
correctness. the correctness of the instrument, which circumstance I hope
justifies me in saying, that it is the only instrument of reflec-
tion that I know, so wellcalculated to prove itself. I beg
pardon for being so tedious; I assure you that I can make the
instrument better than I can write or talk about it.
I have the honour to be, Sir,
Your humble servant,
; JAMES ALLAN.
Blewitt’s Buildings, Jan. 16, 1811.
Testimonials A certificate was produced from Captain H. C. Coxen, R.N.
inits favour. dated February 5th, 1811, stating his opinion, that the dark
screens which are fixedto Mr. Allan's reflecting circle, so as to
act in the manner they do in a sextant, are improvements on
the reflecting circle of Mr. Borda, which are not so fixed.
That it must be evident, even to the least experienced
mariner, that there are frequent occasions, in taking the altitude
of the sun, to change the screens alternately, in the shortest
possible
IMPROVED REFLECTING CIRCLE: 115
possible time, which cannot be effected in near so short a time
by screens which take off and on, as in Borda's reflecting
circle.
Captain Mackay, who has commanded the Lord Forbes, in the
Jamaica trade, for twenty years, stated, that the manner in
which Mr. Allan’s screens are fixed in his reflecting circle isa
great improvement. That from not being obliged to take out
thé shades when the sun is clouded, the object is not lost; and
that when an instrument is obliged to be taken from the eye,
to fix the screen in the old mode, the object is Jé8t.
That by this instrument being a reflecting circle, it makes
sure of a horizontal plane well divided, which can hardly be
the case in a portion only of a circle.
That Mr. Allan’s is the most complete instrament he has
ever seen, and that he shall always take one with him to
sea.
Description of the Drawing of Mr. James Allan's Improve-
ment on the Reflecting Circle of Borda. P). II.
The reflecting circle, first invented by Tobias Mayer, of Got- Description of
tingen, and afterwards improved by the chevalier La Borda, Mr.Allan’sim-
of Paris, is an instrument, which in its principle admits of Ree
such a degree of accuracy, as to be’ of the most important
service to navigators; but it has hitherto been constructed
in such a manner, that the inconveniences attending the use
of it have prevented its general adoption among seamen: any
contrivances, therefore, tending to diminish these inconve-
niences, were deserving of the Society's notice. The con-
struction of Borda’s circle, as it has hitherto been made,
is minutely detailed in Dr.Rees’s New Cyclopzdia, article, Cir-
cle; and the mode of using it is there explained; it will be
therefore unnecessary to describe any thing more of the circle
delineated in pl. III, than is essential to the elucidation of the
improvements made by Mr. Allan.
The first of these is in the mode of applying the dark glasses, Application of
which are fixed on joints, so as to turn back out of the way, the dark glass-
in the same manner as in the sextant. In the old instrument
these glasses were fitted into sockets provided with tenons on
the indexes, and fastened by a milled head screw, which took
much time to change them. The second is the addition of
[2 double
116 IMPROVED REFLECTING CIRCLE. |
Double ver- double verniers to the index, carrying the telescope and horizon
niers. glass; these read upon opposite sides of the circle, and if a
difference is observed between these readings, by taking the
mean of them the errour arising from any eccentricity the index
Centringofthe may haye, will be corrected. And the third consists in fixing the
index glass. index glass upon an axis, accurately fitted into the centre of the —
circle, By this means it is assured, that the index glass, in turning
round, shall always be exactly perpendicular to the plane of
the circle. In the old method, when the index-bar was merely
fitted on a pin &xed in the centre of the circle, it was impossible
to make the circle so perfectly flat, or keep the index so
Explanation of accurately in contact with it, as by having an axis. To explain
the plate. these improvements more perfectly, the reader is referred to
plate III, which contains a perspective view of the instrument ;
A, is the circle with six arms; B, is the index carrying the
telescope C, and the horizon-glass D, with the two clusters of
dark glasses Eand F. At the opposite ends of this index are the
two verniers a and J; the former has the clamp screw and slow
movement attached to it ; consisting of a screw c, which fixes
the index to the circle; and dthe tangent screw, which will
move the index a small quantity when turned, to adjust it
accurately. Gis the index mirror screwed upon the index H,
which has alsoa vernier, and a clamp and tangent screw e e,
similar tothe other. Iis the handle by which the instrument is
held when in use ; it is fitted to a socket K, which is screwed te
the centre of the circle, and is unscrewed from the circle when
packed away. The handle is fitted to a springing socket, so as
to turn round upon the socket K, that it may be turned to any
side of the circle for the convenience of holding it; it may be
fastened by a small milled nut, seen in the figure, which binds
the ends of the spring socket together.‘ L is a magnifying
glass for the purpose of reading the divisions of the verniers ;
itis fitted upon a pin screwed into the indexes, and may be
applied to either. The figure 2 in the corner of the plate is a
section, showing the construction of the central part of the
- circle, where Mis a section of the thickness of the circle, with
a hole through the centre, and a recess turned out in the lower
side to receive a centre piece N, which is fixed in with three
smal] screws ; a hole is turned in the centre of this piece, and
an axis O is fitted into it with the utmost accuracy; this axis
has
IMPROVED REFLECTING CIRCLE.
has a flanch on the upper end, by which it is screwed to the
index H, and upon this, the under glass G, fig. 1, is fastened,
by other screws passing through a piece projecting from the
back of it. The axis is held in its place bya collet 7, fitted
on a square part of it, and held fast bya-screw s; beneath this a
piece is fixed on in the centre of the circle, the edge of its fanch
being shown by ¢ in fig. 1; it is part of the screw which holds
on the spring socket K, for the handleI. The upper end of
the centre piece N, which comes up above the circle, is turned
extremely true, and upon this the index B is fitted, or rather a
brass ring v screwed to it, soas to turn round upon it as a
centre.
The telescope C is fixed to the index by two cocks and
by two screws XX, in these it can be raised up or lowered,
to adjust the different brightness of the two objects seen in the
horizon glass D, the one reflected from the central mirror G,
and the other seen directly through it. The dark glasses at E
are intended to moderate the light of the sun, in passing from
the index to the horizon glasses ; the frames containing these
glasses have holes E through them, to see through the telescope
and horizon glass; the other dark glasses, F, are situate behind
the horizon glass D, and may be turned up ordown, as occasion
requires.
The instrument is used in the same manner as the common
reflecting circle ; the angle being first taken on one side of
the parallelism of the glasses, and then on the other; so that
the angle is doubled ; then it is repeated on a fresh part of the
circle, as many times as the observer thinks proper, and the
‘product divided by the number of observations taken. The
‘mode of taking these observations is explained at full in Dr.
Rees’s Cyclopedia, and in Dr. Mackay’s publication on the
means of finding the longitude.
VI.
118
VEIL
METEOROLOGICAL JOURNAL,
1812. | Wind.| Max. ; Min. |
7th Mo.
ee
JuLy 30|N W| 29°96) 29°80
31S ‘Wj 29°96) 29°80;
sth Mo.
Ave. 1| Var. | 29°86) 29°80
2\N EF 29°86, 29°80
3| Var. | 29°85} 29°80
4iIN_ -E} 29°90) 20°85
5S. W} 29°95, 29°90
6| Var. 30°00 29'05
7iIN W 30°00 20°95
SIN W| 29°96, 29:04
QIN W| 29°97, 29°96,
10\N W{| 29°97) 29°96,
11] Var. | 30°07| 29°96
12iN- E| 3014 30 07]
13) N | 30°15 30°14
14iIN E 30°15, 30°12
15) oh 30°12) 30'07
16, E 30:06 30°05
17/8, E 30°05, 29°98
18\S E} 29° 98 29°70
19|S W)| 20°96 29°76
20; W | 30°00 29°98)
21|S: W| 2997, 29°94
22! W { 3005 29:97
*23\S W| 30°04 29°86
24'S Wy 30:10 29°86
25/5 Wy 30°10 30°04
26;'N W} 30:04 29°96
Se ee TT
al
Meda.
29°830, 61 | 53
29'830) 64 | 54
29'825, 63 | 52
29'°875| 65 | 50
29'925| 57 | 50
29°075| 63 | 47
29°975| G1 | 49
29°950) 57 | 51
29'965, 57 | 45
29'965) 58 | 53
30'015| 63 | 49
30°105| 57 | 44
30'145| 64 | 43
30°135| 67 | 49
30 095) 65 | 50
30.055| 68.| 54
30:015) 73 | 55
29'870, 78 | 58
29°860| 72 | 55
29°990; 71 | 55
29°955| 69 | 57
30°010, 68 | 53
29.950) 70 | 60
29.980! 66 | 47
30°070| 69 | 52
30°000} 67 | 53
BaroMETER. | THERMOMETER. |
Max. | Min.
———_
pees | es | ees
Med.
605
60°0
See | meee | enn ee | sence omer
30°15 29° 76 sl O68] 78 | 43 |57°91
Evap. Rain
j;—|—
|
y
‘20 ‘os
— | ‘O2
— ‘| °10
ee ‘02
— "32
— ‘Al
5) all il 23
om ‘02
— ‘05
18 C
‘SA
‘50 | “OL
An ‘S)
‘606 *
— "05
35
2°75 | 1°34
The observations in each line of the table apply to a period of twenty-four hours
beginning at9 A. M, onthe day indicated in the first column,
the result is included in the next following observation.
A dash denotes that
NOTES,
METEOROLOGICAL JOURNAL. 1 19
REMARKS.
Eighth Month. 4. Wet afternoon. 5. Wet morning.
6. ‘© The day was gloomy : about 4. p. m. avery heavy shower
commenced, which continued for about 20 minutes, then
abated for a short time, but increased again, and continued all
the evening, with thunder and lightning: the barometer was
nearly stationary.” Such were the phenomena at the labora-
tory, where there fell 1°39 inches of rain. At Plaistow, two
miles distant, there appears to have fallen only 0°41 inches of
rain, and [ find only this note, ‘‘ Thunder in the afternoon.”
13. Foggy morning: a stratus at night. 14. The same.
17. Thesame: Lunar halo. 18. Some lightning during the
night. 21. Thunder between one andtwop.m. 24. Bright
moonlight. 28, The wind this night very high. 30. Very
showery.”
RESULTS.
Prevailing winds westerly.
Barometer : highest observation 30°15 inches ; lowest 29°76 inches ;
Mean of the period 29°968 inches.
Thermometer : highest observation 78° ; lowest 43.
Mean of the period 57°91°.
Evaporation 2°75 inches. Rain 1°34 inches.
PLAIsTow. L. HOWARD.
Ninth Month, 15, 1812.
P. S. The observations on the barometer, wind, and evaporation,
with the remarks, for the last two months, are chiefly due to my friend,
John Gibson. The account of temperature and rain was carefully
kept (during my absence) at Plaistow.
120 COMBINATIONS OF OXIMURIATIC ACID AND METALS,
VII.
An Account of some Experiments on the Combinations of diffe-
rent Metals and Chlorine, &c, By Joun Davy, Esq. Com-
munivated by Sir Humpury Davy, Kt. LL. D., Sec. BR. S.
(Concluded from p. 21.)
4. On the Combinations of Chlorine with Manganese, Lead,
Zinc, Arsenic, Antimony, and Bismuth.
Only 1 com- HAVE attempted, by several methods, to obtain more
pound with il than one combination of these different metals and oe
some metals.
tine, but without success.
Compound of I have procured a compound of manganese and chlorine, by
seid and man. Vaporating to dryness the white muriate of this metal, and heat-
ganese. . ing to redness the residue ina glass tube, having only a very
small orifice. Mluriatic acid vapour was produced, and a fixed
compound remained, which required a red heat for its fusion,
aud was not altered by the strongest heat that could be given to
it in the glass tube ; but was rapidly decomposed when heated
in an open vessel, muriatic.acid fumes being evolved, and oxide
of manganese formed, which was black or red, according to
the intensity of the heat applied. The compound of manga-
nese and chlorine is a very beautiful substance, it is of great
brilliancy, generally of a pure delicate light pink colour, and of
a lameliar texture, consisting of broad thin plates.
Mode of frees There is not much difficulty in obtaining this compound
ing it from . : : se
Seca: pure. Iron, with which manganese is commonly contami-
nated, may be separated by two or three repetitions of the solu-
tion of the compound in water, the evaporation to dryness of
the clear filtered muriat, and fusion of the residue procured by
evaporation. Indeed, J think this a good general method for
purifying manganese from iron. One of the combinations of
ihe Jatter metal and chlorine being volatile, heat must sepa-
rate it from the compound of manganese. And I have thus
obtained it so free from iron, that triple prussiate of potash,
added to its solution in water, gave merely a white precipitate,
without the slightest tint of blue.
Its properties. This compound deliquesces when exposed to the atmo-
sphere, and is converted into the white muriate. Like ferrane,
it affords a trifling residue when heated with water. The re-
sidue
COMBINATIONS OF OXIMURIATIC ACID AND METALS. TQ
sidue is oxide of manganese, white at first, but soon becoming
red, and even black; it varies in quantity, according to the
exclusion of air in the formation of the combination.
50 grains of the compound dissolved in water, with the ex- Analysis.
ception of 1 grain; this residue was separated by decantation
of the fluid, washed, dried, and heated to redness, it was in
the state of black oxide. The colourless solution was preci-
pitated by nitrate of silver. The horn silver formed, when
dried, was equal to 108 grains. Hence, omitting the 1 grain
of mixed oxide, 100 of this compound appear to consist of
54 chlorine
46 manganese
100
The horn lead, that I have analysed, was made by the de- Horn lead.
composition of the nitrate of lead by muriatic acid, and it was
well washed, dried, and fused in a glass tube with a small
orifice. The strongest red heat that I could apply to it, under
these circumstances, did not occasion its sublimation.
50 grains of it, that had been fused, were dissolved in water. Analysis.
This solution, heated with nitrate of silver, afforded 52°65 grains
of dry horn silver. Hence 100 of horn lead appear to be com-
posed of
25°78 chlorine
74°22 lead
100°00
As this compound, when decomposed by an alkali, affords
the protoxide of lead, it may be called plumbane.
The butter of zinc I have examined was obtained by eva- Butter of zinc.
porating to dryness the muriate of this metal, and by heating
to redness the residue ina glass tube. This compound is not
volatile at a strong red heat in a close vessel, it fuses before
it acquires a dull red heat, and on cooling it goes through
several degrees of consistence, being viscid before it.becomes
solid.
This compound, when heated with water, affords a small
residue of oxide of zinc, which, as in the preceding instances,
may be considered as in the state of mechanical mixture.
Tn consequence of its powerful attraction for water, it is a
very
122 COMBINATIONS OF OXIMURIATIC ACID AND METALS.
very deliquescent substance ;.on this account it is necessary
to weigh it in water to avoid errour. 49°5 grains of it, thus
weighed, dissolved entirely in water, with the exception of 1
grain of oxide of zine, which was separated -by decantation,
and dried and ignited, and its quantity ascertained to be as
stated. The solution precipitated by nitrate of silver afforded
09 grains of dried horn silver. Hence, excluding the 1 grain
of oxide, 100 of butter of zinc seem to consist of
50 chlorine
50 zinc
100
This compound may be called zincane.
Fuming liquor A compound of chlorine and arsenic has been long known,
of arsenic. —_ hearing the name of the fuming liquor of arsenic. It may be
formed in several ways: by the combustion of arsenic in chlo-
rine gas; by heating in a retort a mixture of arsenic and cor-
rosive sublimate, or of arsenic and calomel ; and by the distil-
lation of muriate of arsenic with concentrated sulphuric acid.
The old method by means of corrosive sublimate appears best
adapted for procuring itin a pure state. About 6 parts of
corrosive sublimate to 1 of arsenic are, I find, proper propor-
tions. The mixture of the two substances should be intimate,
and the heat applied to the retort for the distillation of the
fuming liquor, gentle. When the liquor was not colourless at
first, I have purified it by a second distillation.
The fuming liquor of arsenic, it is well known, is decem-
posed by water. The precipitate produced appears ta be
merely white oxide of arsenic, for, independent of other cir-
cumstances, it does not afford the fuming liquor’ when heated
with strong sulphuric acid.
The fuming liquer, when gently heated, dissolves phospho-
rus, but it retains on cooling only a very small portion of this
substance. The warm solution is not luminous in the dark.
The fuming liquor also, when warm, readily dissolves sul-
phur; indeed sulphur fused in the liquor seems capable of
combining or of mixing with it in all proportions ; but on cool-
ing the greatest part of the sulphur is deposited, and assumes
a fine crystalline appearance; the form of the crystals was
apparently the octahedron. This deposition seems to be merely
sulphur
Its properties.
COMBINATIONS: OF OXIMURIATIC ACID AND METALS. 123
sulphur with a little of the faming liquor between the inter-
stices of the crystals, for the crystals bear washing, and be-
come tasteless superficially, but remain still acid internally,
where the water has not penetrated.
It likewise dissolves resin. That which was called rosin
was the subject of experiment. The solution was of a blueish
green colour; but when gently heated it became brown, and
remained so on cooling. The portion of resin the fuming
liquor is capable of taking up is very considerable; when the
resin was added in excess, a viscid mixture was formed. The
resinous solution was decomposed by water, and the resin was
separated, apparently unaltered, mixed with white arsenic.
The fuming liquor is capable of combining with oil of tur-
pentine and with olive oil. When the mixture was made with
either of these oils, there was a considerable elevation of tem-
perature, and a homogeneous colourless fluid was in each
instance obtained.
In these and some other properties, the fuming liquor of Analogous to
arsenic is analogous to the fuming compounds of chlorine and pee a
sulphur, and chlorine and phosphorus; these two, having the sulphur and
power of dissolving sulphur, and phosphorus, and resin, and Phosphorus.
of entering into union with the fixed and volatile oils.
It is difficult to ascertain the proportion of the constituent Its component
- parts of this compound by the ordinary modes of analysis; I P3tt-
have chosen therefore a synthetical method in preference;
and from repeated experiments I find, that 2 grains of arsenic
require for complete conversion into the faming liquor 4 cubic
inches exactly of chlorine gas.
The experiments were thus. conducted: the arsenic in one
piece-was put into a small glass retort having a stop-cock'; the
retort was exhausted, and a known volume of. chlorine gas. was
admitted from a graduated receiver by means of other stop-
cocks and the absorption of chlorine, after the entire conver-
siom of the metal into the fuming liquer, was considered as the
proportion condensed by the arsenic. :
Now, since 100 cubic inches of chlorine gas weigh just 76°5
grains, 2 grains of arsenic combine with 3°06 grains of chio-
rine, the weight. of 4 cubic inches of the gas.- Hence 100 of
the fuming liquor appear to consist-of
6048
1O4, COMBINATIONS OF OXIMURIATIC ACID AND METALS.
60°48 chlorine
39°52 arsenic
100'00
As the fuming liquor gives the white oxide when decom-
posed by water, arsenicane may be substituted for its old name.
Butter of anti- The butter of antimony isa well known substance. That
rae which I have examined was obtained by heating together cor-
rosive sublimate and antimony, or antimony and calomel ; and
was always purified by a second distillation at a low tempe-
rature. The best’ proportion of corrosive sublimate and the
metal for making the compound, I have found to be about 23
parts of the former to 1 part of the latter.
its properties, ‘The butter of antimony, like arsenicane, is capable, when
rendered fluid by heat, of dissolving resin and sulphur, and
of combining with the fixed and volatile oils. It affects the
oil of turpentine very like the liquor of Libavius; the action
* is considerable, much heat is produced, and the oil is rendered
brown. |
When the butter of antimony is decomposed by a suffici-
ently large quantity of the hydrosulphuret of potash, that
compound is formed, which is commonly called the golden
sulphur of antimony ; and which, when decomposed by heat,
.I have found to afford merely water and sulphuret of anti-
mony*.
Its component To ascertain the proportion of antimony in the butter of
ota antimony, 60°5 grains of this substance, colourless and crystal-
lized, weighed in water, were heated in a solution of hydro- »
sulphuret of potash. The whole of the antimony was dissolved,
and the hydrosulphuret of potash being in excess, there was
no precipitation on cooling. The solution was decomposed by
Golden sul- * These results appear to me to demonstrate the truth of Mr,
phur of anti- Proust’s opinion, that the golden sulphur is a hydrosulphuretted oxide
5 Pf of antimony. From my experiments the only difference of composition
between kermes mineral and the preceding compound seems to consist
inthe former containing a smaller proportion of sulphuretted hidro-
drogen than the latter; for I have obtained by the decomposition of
kermes mineral, by heat, a compound of sulphuret of antimony and
protoxide ; and I have converted kermes into the golden sulphur, by
means of water impregnated with sulphuretted hidrogen.
muriatie
~ COMBINATIONS OF OXIMURIATIC ACID AND METALS,
muriatic acid, and the golden sulphur thus thrown down was
collected on a filter, well washed, and dried; heated slowly to
redness in a-glass tube, steam in plenty was disengaged with
very slight traces of sulphur, and sulphuret of antimony re-
mained, which, fused into one mass, weighed 45 grains. Ac-
cording to the experiments of Proust, which I have repeated
with the same result, sulphuret of antimony contains 74°1 per
cent of metal.- Hence 45 grains of sulphuret, or the 60°5 of
butter of antimony, from which the sulphuret was procured,
must contain 33°35 of metal ; and considering the remainder
27°15 of the 60°5 as the proportion of chlorine, 100 of the
‘butter of antimony seem to consist of
39°58 chlorine
60°42 antimony
: - 100°00 . |
This compound, as it yields, when decomposed by water, the
_ submuriated protoxide, may be called antimoniane or stibiane.
125.
A compound of bismuth and chlorine has been long known, Butter of bis-
bearing the name of the butter of bismuth., It is obtained both muth.
when bismuth is heated with corrosive sublimate and calomel.
2 parts of corrosive sublimate to one part of metal I have found
good proportions for its preparation. There is some difficulty
in procuring it pure, and entirely free from the mercury re-
vived ; this is most readily effected by keeping the butter of*
bismuth in fasion, ata temperature just below that at which
mercury boils; the mercury slowly subsides and collects in
the bottom of the vessel, and this operation, continued for an
hour or two, affords a pure, or nearly pure, butter of bismuth.
Thus prepared, it is of a grayish white colour, opaque, un-
crystallized, ana of a granular texture. In a glass tube, with
a very small orifice, it bearsa red heat without subliming.
As a hydrosulphuret of bismuth is produced when the butter
of bismuth is heated with the hydrosulphuret of potash; and.
as this hydrosulphuret, like that of antimony, affords, when
decomposed by heat, a sulphuret and water; I have applied the
same mode of analysis to this compound as to the last.
55. grains of butter of bismuth were decomposed in a warm Analysis of it,
solution of hydrosulphuret of potash. The dark brown. hy-
drosulphuret of bismuth thus formed, and not dissolyed, was
Mb ancty collected
196 COMBINATIONS OF OXIMURIATIC ACID AND METALS.
collected on a filter; the hydrosulphuretted soiution was
decomposed by muriatic acid, the slight precipitate of hydro-
sulphuret produced was added to the first portion, and the
whole was well washed, dried, and heated to redness in a
glass tube ; the sulphuret of bismuth thus obtained, fused into
one mass, weighed 44°7 grains. I had previously ascertained
the proportion of metal in this sulphuret, and found it to be
81'8 per cent. 44°7 grains of sulphuret, or 55 grains of the
butter, must therefore contain 36°5 grains of bismuth ; and
hence, 100 of bismuth appear to‘consist of
33°6 chlorine
66°4 bismuth
100'0
The butter of bismuth may be called bismuthane.
Singularities Among the preceding combinations of the metals and chlo-
an oe rine, there is a surprising difference in respect to volatility
regard to yo-and fusibility. Iron and manganese, two difficultly fusible
peas and fu- metals, form with chlorine readily fusible compounds, and a
combination of the former metal and chlorine is even volatile ;
the compounds of tin and chlorine, and of chlerine and anti-
mony, are very volatile substances, though the metals them- —
selves are fixed at very high temperatures; on the contrary,
the combinations of chlorine with bismuth, zinc, and lead, do
“not exceed in fusibility ; indeed are not quite so fusible as the
metals themselves. I can offer no explanation of these pheno-
mena.
Singularity of | Another singularity attending the liquid fuming compounds
the fuming —_ of chlorine, such as the liquor of Libavius, the fuming liquor
compounds. : 4 . i s
of arsenic, and the oxymuriates of sulphur and phosphorus, is,
that they do not become solid at low temperatures. I have
reduced, by means of a mixture of snow and muriate of lime,
the temperature of all these substances 20 degrees below the
zero of Fahrenheit’s thermometer, but without affecting their
liquidity.
Influenceofat- The influence of atmospheric air on the compounds of the
mospheric ait metals and chlorine at high temperatures is curious, and wor-
at high tempe- ; : ae ee ee
ritdres: thy of particular attention. The combinations of chlorine with
lead, zinc, copper, and bismuth, appearto be volatile in open
vessels, and fixed in closed ones, How moist air operates in
these
COMBINATIONS OF OXIMURIATIC ACID AND METALS. 127
these instances, it is difficult tosay. In other cases, where it
evidently acts chemically, the changes explain themselves ;
thus, when the compounds of iron and chlorine, and of man-
ganese and chlorine, are heated in the open air, hygrometrical
water of the atmosphere seems to be decomposed, as muriatic
acid fumes are produced, and oxides of the metals formed.
Probably the. volatility of the other compounds is connected
with similar circumstances. This action of moist air has Action of —
hitherto been much neglected ; it is certainly worthy of being ae Et
more fully inquired into, bothin a theoretical and practical
point of view. Its importance in practice is exemplified in the
reduction of horn silyer, and in the formation of several of
the compounds of chlorine and the metals; if moist air be
admitted in these operations, the silver will be lost, and the
compounds not formed.
Guided by analogy, I have been led to try whether the Action of heat
muriate of magnesia, which is readily decomposed by heat in pera arha
the open air, would not, when the air was excluded, by intro- magnesia.
ducing it into a glass tube with avery small orifice, afford a
permanent compound. The result was agreeable to my ex-
pectations ; I obtained, by strongly heating the muriate for a
quarter of an hour, a substauce like enamel in appearance,
being semifused, and which appeared to bea mixture of mag-
nesia and the true compound of magnesium and chlorine, for
heated with water magnesia was separated, and a muriate of
magnesia formed.
5. On the Relation between the Proportion of Oxigen and Chlo-
_ rine in Combination with several Metals.
Errours being very common in chemical analyses, even in ane of
those conducted most skilfully and carefully, all possible means Sopa
should be taken to discover them; and no means, I think, pro- of the accu-
mise to be more effectual for this purpose, than the general oo pi aaa:
analogy of definite proportions. From a great variety of facts,
it appears that oxigen and chlorine combine with bodies in
the ratio of 7°5 to 33°6. With 1 part by weight of hidro-
gen, for example, 7°5 of oxigen unite to form water ; and
33°06 of chlorine unite with the same proportion to produce
Muriatic acid gas. To judge therefore of the accuracy of the
analyses of the preceding combinations of the metals and
chlorine,
128
Applied to the
compounds of
copper ;
eftins
(Experiments
on the oxides
ef tin.)
COMBINATIONS OF OXIMURIATIC A€ID AND METALS.
chlorine, it is only necessary to compare them with the ana-
lyses of the oxides of the same metals. If the two agree,
there will be reason to consider them both correct, but should
they disagree, there is equal reason for supposing one or both of
them to be wrong, .
Thus as the orange oxide*of copper is analogous to cuprane,
and the brown oxide to cupranea, the oxigen and chlorine
should be to each other in these compounds as 7'5 to 33°6.
And from comparison of my analysis with those of Mr. Cue-
nevix and Mr. Proust, it appears, that in the two first;
copper being as 60, the oxigen is to the chlorine as 7°79,
instead of 7°5 to 33°77, instead of 3°36; and in the two last
as 7°5 to 33'6, or as 15 to 67'2. Coincidences as near as might
be reasonably expected,
There is not the same agreement between Mr. Proust’s
analyses of the oxides of tin andthe preceding ones of the
combinations of this metal and chlorine. This discordance
induced me to repeat my analyses ; and, obtaining the same
result as at first, I directed my attention to the oxides of tin,
and made the following experiments to ascertain the propor-
tion of their constituent parts.
42°5 grains of tin, which had been precipitated from the
muriate of this metal by zinc, were heated with nitric acid in a
platina crucible, and slowly converted into peroxide; the acid
and water were driven off by gentle evaporation at first, and
afterward by a streng red heat, continued for a quarter of an
hour. The peroxide thus produced was of a light yellow
colour, and being very gradually dried, it was semitranspa-
rent, and hard enough to scratch glass; it weighed 54°25 grains.
Hence, as.42°5 grains of tin acquire, on conversion into per-
oxide, 11°75 grains of oxigen, this oxide appears to contain
21°66 per. cent of oxigen, just the quantity found in the
native oxide by Klaproth, instead of 28, the proportion stated
by Proust.
Mr. Berthollet, jun., has shown, that Mr. Proust’s estimate
of 20 per cent of oxigen in the protoxide is incorrect. To
ascertain the true proportion, 20 grains of tin were dissolved
in strong muriatic acid in a retort ccnnected with a pneumatic
apparatus, and without the assistance of heat ; 16 cubic inches
of hidrogen gas were produced. (Barom. 30, thermom. 60.)
As
COMBINATIONS OF OXIMURIATIC ACID AND METALS.
As the production of this quantity of hidrogen indicates an
absorption of oxigen by the tin equivalent to 8 cubic inches,
or (as 100 cubic inches weigh 34:2 grains) to 2°736 grains, the
protoxide of tin appears to contain 11°99 per cent of oxigen.
These analyses of the oxides, compared with those of the
combinations of tin and chlorine, are found very nearly to
agree. The ratio of oxigen to chlorine in the first two simi-
lar compounds, the tin being as 55, is as 7'5 to33'4; and in
the last two, viz. the peroxide and the liquor of Libavius, as
7'6 to 33°5, or as 15°2 to 67.
As the black oxide of iron is formed by the decomposition of iron;
of ferrane by a solution of potash, and the red oxide by that
of ferranea, it is evident, that these oxides and combinations
of iron and chlorine should coincide in the proportions of their
constituent parts. This appears from the analyses* of Dr.
Thompson to be nearly the case ; for, iron being as 29°5, the
oxigen isto the chlorine in the black oxide and ferrane as 8
instead of 7°5 to 33°6; and in the two others as 8 to 33°6, or
as13°2 to'55°5. Here the agreement is less than in other
instances ; but this is not surprising, eonsidering the different
estimates of the proportions of oxigen in the oxides of iron,
and the difficulty of ascertaining them correctly.
The yellow oxide of lead, and the white oxides of antimony, of other me-
; ; ‘ sas ens et
bismuth, zinc, and arsenic, are formed, when the combinations
of these metals and chlorine are decomposed by a solution of
potash. But on comparison with the best analyses of the
oxides, there is not, excepting in the case of zinc and arsenic,
that coincidence of proportions which might be expected.
Zinc being as 34:5, the oxigen in the oxide, from the analysis of zine;
>
of Proust, isto the chlorine as 7°5 to 34°4; and the arsenic of arsenic;
being as 21°9, the oxigen, from the analysis of the same che-
mist, is to the chlorine as 7'3 to 33°6. The analyses of the
oxides of the other metals being at variance with those of the
chlorine combinations, I was induced to make the following
experiments, with the hope of discovering the cause of the
difference.
100 grains of lead, which had been precipitated from the of lead;
nitrate of lead by zinc, were dissolved in nitric acid, and thrown
down by carbonate of potash. This precipitate of carbonate of
® Nichelson’s Journal, vol. XXXVII, p. 375,
Vou. XXXIII, No. 152.—Ocrogper, 1812. K silead
COMBINATIONS OF OXIMURIATIC ACID AND METALS.
lead was well washed and dried, and heated to dull redness
for a quarter of an hour ina platina crucible: by this treat-
(Oxideof lead) Ment all the carbonic acid was expelled ; the remaining yellow
of antimony;
(Oxides of an-
timony.)
oxide weighed 107°7 grains, and it dissolved in muriatic acid
without effervescing, and without affording any residue of
brown oxide. Hence, the yellow oxide of lead appdars to con-
tain 7°15 per cent of oxigen. And this proportion, of oxi=
gen in the oxide compared with that of chlorine in plumbane,
lead being as 97°2, appears to be in the ratio of 7°5 to 33°8,
instead of that of 15°6 the estimate of Klaproth, or of 11:2
the estimate of Dr. Thompson to 33’8. Klaproth might have
been misled by considering the hydrated oxide as a true white
oxide free from water.
According to Mr. Proust, the peroxide of antimony contains
23 per cent of oxigen, and the protoxide 18*. I have
repeated this chemist’s experiments ; my results, in which the
peroxide is concerned, agree with his; but there is not the
same concordance in those relating to the protoxide. The
protoxide I used was either prepared by the decomposition of
the butter of antimony, or of the suiphate, by a boiling solution
of carbonate of potash. This oxide, in its purest state, I have
always found, as Mr. Proust describes it, of a light fawn colour
before fusion, and afterward in mass of a gray colour, and of
a radiated crystalline texture. 100 grains of it that had been
fused were heated in the state of powder with strong test
nitric acid in a platina crucible : when nitrous gas ceased to be
produced, the excess of nitric acid was expelled by a gentle
heat, and the oxide was heated to dull redness ; the increase
of weight after this was equal to 10°4 grains: nitric acid was
again added, and the process repeated, but without any alte-
ration of weight being produced. Hence, as the peroxide con-
tains 23 per cent, the protoxide seems to contain 15 per cent;
which proportion of oxigen very nearly agrees with that of
chlorine in the butter of antimony; for, antimony being as
42°5, the former is to the latter as 7'5 to 34’6, instead of 33°6,
I put some confidence in this estimate of the proportion of oxi-
gen io the protoxide, not only on account of its agreement
with the analysis of the butter of antimony, but because it
was confirmed on the repetition of the experiment.
* Journal de Physique, Tom. LV,
Klaproth
be
COMBINATIONS OF OXIMURIATIG ACID AND METALS. 131
Klaproth concludes from his experiments, that the oxide sean bis-
of bismuth, prepared by means of nitric acid, contains 17°7 C Oxide of bis-
per cent of oxigen ; and in consequence this oxide has been muth.)
considered distinct from that which is formed by direct calci-
nation of the metal, and which contains a much smaller pro-
portion. But there is reason to believe, that this difference
"does not really exist, and that there is only one known oxide
of bismuth, and that Klaproth’s oxide was a hydrated oxide;
for 1 have found that 100 grains of bismuth, converted by
nitric acid into oxide, precisely in the same manner as the
protoxide of antimony was more highly oxidated, gained only
111 grains. Klaproth did not heat his oxide to redness, and
hence apparently the discordance. From the above result,
which I have confirmed by repetition of the experiment, oxide
of bismuth seems to contain 10 per cent of oxigen; and bis-
muth being as 67°65, the oxigen in the oxide is to the chlorine
in the butter of bismuth, as 7°5 to 34'2.
6. On the Relation between the Proportion of Sulphur in the
Sulphurets, and the Proportions of Chlorine in some of the
Combinations of Chlorine and the Metals.
’ The last section afforded proofs of the useful application of Proportions
the general analogy of definite proportions in correcting the skim
results of chemical analyses. In the present section, it is my those of the
intention to pursue a little farther the plan that I have adopted ad eb =
in the preceding, and to apply another test to the analyses of acid.
the combinations of the metals and chlorine, by comparing
some of them with the combinations of the same metals and
sulphur.
I was first led to examine the sulphurets of tin on a different Feel
account. Aurum musivum, it has been observed, is formed sf dient
when stannane is heated with sulphur. According to Mr. sivum.
Proust, this substance is a sulphuretted oxide of tin. Were
this opinion correct, an argument might evidently be deduced
from it in favour of the existence of oxigen in chlorine.
To satisfy myself respecting this, I endeavoured to ascertain
whether any sulphureous acid gas is produced by the decom-
position of aurum musivum by heat, as it is commonly asserted.
I heated to redness in a bent luted green glass tube, connected
with a pneumatic mercurial apparatus, about 20 grains of
2urium musivum, prepared by the decomposition of stannane
K 2 with
1382 COMBINATIONS OF OXIMURIATIC ACID AND METALS.
with sulphur, no more gas was produced than the expansion
by heat occasioned, sulphur sublimed, and a gray sulphuret
of tin remained. ‘These results I have several times obtained,
and not only with aurum musivum prepared as the preceding,
but with some also made according to WoutrFe’s process. As
no sulphureous acid gas was produced, and as sulphur sub- |
Jimed, it may be concluded, that auruam musivum differs merely
from the gray sulphuret in containing a larger quantity of
sulphur. My next object was to ascertain the exact propor-
tion of sulphur in both these sulphurets, for the sake of com-
parison with the combinations of tin and chlorine.
Poraponces 100 grains of tin in a finely-divided state, as precipitated
pe saipbuc from the muriate of this metal by zinc, were heated in a glass
ef tin, tube intimately mixed with sulphur, the combination of the
two was accompanied with vivid ignition, the sulphuret formed
weighed 127°3 grains, and, broken, it appeared perfectly ho-
mogeneous ; it was pounded, and again heated with sulphur ;
but the excess of sulphur being expelled, the fused sulphuret
had not increased in weight. The second time I made this
experiment, I obtained the same result.
and of aurum SO grains of aurum musivum, purified from mixed sulphur
musivum, by exposure in a close vessel to a dull red heat, were decom-
posed by a bright red heat in a small green glass tube nicely
weighed, and having only a very small orifice; the loss of:
sulphur, by conversion into the gray sulphuret, was equal to
93 grains. Hence, as 40°7 grains of gray sulphuret contain
8°72 grains of sulphur, 50 grains of aurum musivum appear
to contain 18°02 grains,
Ratioinwhich Lhe ratio in which sulphur combines with bodies is to that
sulphur com- in which oxigen and in which chlorine combine, as 15 to
P00 pie 7°5 and 33°6. This appears from the proportions of the con-
with oxigen, stituent parts of sulphuretted hidrogen and sulphureous aeid
Pair A tae gas; for I have found 100 cubic inches of the former to weigh
36°64 grains, and 100 of the latter 68°44 grains. In the com-
parison, therefore, between the sulphurets of tin and the com-
binations of this metal and chlorine, 15 by weight of sulphur
are equivalent to 33’6 of chlorine.’ And the tin being as 55, it
appears from the analysis of the gray sulphuret and stannane,
that the sulphur is to the chlorine as 15 exactly to 33°4; and
from
COMBINATIONS OF OXIMURIATIC ACID AND METALS, 133
from the analysis of the other two compounds, aurum musivuni, °
and the liquor of Libavius, as 15°5 to 33°5, or as 31 to 67.
The proportions of sulphur in the two sulphurets of iron Sulphurets of
do not accord with the proportions of oxigen in the oxides, “°"
or of chlorine in the chlorine combinations ; but I am yet ig-
norant of the cause of this difference.
100 grains of lead, heated with sulphur in a glass tube, of lead,
afforded, in two trials, 115°5 grains of fused sulphuret. Hence,
lead being as 97°2, the sulphur is to the chlorine in the re-
spective combinations as 15'09 to 33°8.
Sulphuret of antimony contains 25°9 per cent of sulphur, % 2ntimony,
Hence, antimony being as 42°5, the sulphur in the sulphuret is
to the chlorine in the butter of antimony, as 14°86 to 34°6.
100 grains of bismuth heated with sulphur afforded 122°3 and of bis-
grains of sulphuret. Hence, bismuth being as 67°5, the sulphur apt
is to the chlorine as 15°08 to 34:2.
In the following table, the proportions are collected in which
chlorine, sulphur, and oxigen combine with several metals ;
the numbers representing the metals are kept constantly the
same, for the greater facility of comparison.
Copper 60 + 32°77 chlorine = cuprane. Compapeps of
+ 67°20 ditto = cupranea. oniatee ite
+ 7°79 oxigen = orange oxide. gas, oxigen,
+ 15°00 ditto = brown oxide. aad EY
Tin 55 + 33°40 chlorine = stannane.
+ 67°00 ditto = stannanea.
+ 15°00 sulphur "= gray sulphuret.
+ 31:00 ditto == aurum musivum.
+ 7°50 oxigen = protoxide.
: + 15°20 ditto = peroxide.
Tron 20'5 + 33°60 chlorine = ferrane.
+ 55°50 ditto = ferranea,
+ 8°00 oxigen = black oxide.
+ 13°20 ditto = red oxide,
Manganese 28°4 + 33°60 chlorine.
Lead 97°2 + 33°80 chlorine = plumbane,
+ 15°09 sulphur = sulphuret.
+ 7'50oxigen = yellow oxide,
Zinc 34°5 + 34°40 chlorine = zincane,
+ 7°50 oxigen = oxide,
Arsenic
1 3gh: COMBINATIONS OF OXIMURIATIC ACID AND METALS.
Arsenic 21°9 + 33°60 chlorine = argenicane.
+ 7°30 oxigen = white oxide.
Antimony 42'5 + 34°60 chlorine = antimonane.
+ 14°86 sulphur = sulphuret.
+ 750 oxigen = protoxide.
Bismuth 67°5 + 34:20 chlorine = bismuthane,
+ 15°08 sulphur = sulphuret.
+ 7°50 oxigen = oxide.
7. Onthe Action of muriatic Acid on some Comlinations of
Chlorine and Metals.
Action of mu- Sir Humpary Davy has pointed out ina great variety of
riatic acid ON instances the existence of an analogy between chlorine and
some Com- r : u i
pounds of oxi- oxigen. He has shown, that the former, united with certain
ae bea ae inflammables, constitutes, like the latter, acid compounds; and
ane me combined with metals, as it has already been observed, sub-
stances similar in many respects to metallic oxides.
I have kept this analogy in view in my inquiries; and, di-
rected by it in my experiments, I have obtained some results
which appear to me to coincide with it.
Thus having been led to try the action of muriatic acid on
different combinations of the metals and chlorine, I have found
many of them capable of uniting with this acid, and of form-
ing compounds not dissimilar to some of those consisting of
acids and metallic oxides. F
Corrosive sublimate, stannane, cuprane, and the combina-
tions of chlorine with antimony, zinc, lead, and silver are all
soluble in different degrees in mauriatic acid.
Corrosive sublimate, which is but sparingly soluble in water,
and still more sparingly in the sulphuric and nitric acids, is, I
have ascertained, very readily soluble in muriatic acid. 1 cubic
inch of the common strong acid takes up about 150 grains of
‘this substance, and when gently heated, a quantity far more
considerable, about 1000 grains, The compound thus formed
solidifies on cooling into a crystalline fibrous mass, of a pearly
and brilliant lustre. © It is decomposed by heat, the acid being
first expelled ; and when exposed to the atmosphere, it efflo-
resces, and appears to lose its acid; for, afterward analysed, it
is found to be pure corrosive sublimate.
Corrosive sub-
limate,
Whe
COMBINATIONS OF OXIMURIATIC ACID AND METALS. 135
When I first tried the action of muriatic acid on the diffe- i emcahn ete
rent combinations of chlorine already mentioned, I was not = ana 2
aware, that Krarrorn had before observed the solubility of lead.
horn silver in this acid, and Mr, Cuenevix that of cuprane-
Horn silver, cuprane, and horn lead, are precipitated from
muriatic acid unaltered by water. Both the hot saturated
solutions of the two last compounds deposit crystals on cool-
ing; those from the solution of the former are of an olive
green colour, and of a prismatic form, and consist of cuprane
and muriatic acid ; those from the latter are small white bril-
" liant plates.
Finding the combinations of the metals and chlorine so None of the
generally soluble in liquid muriatic acid, I expected, that some Gn sna
of them might absorb muriatic acid gas; but none that I have tic acid gas.
tried have possessed this property, not even the liquor of
Libavius. Indeed this is not singular, for water is necessary
to the composition of many saline bodies ; neutral carbonate of
ammonia and nitrate of ammonia, for instance, cannot be formed
without the presence of water. Neither is the precipitation of Precipitation
; f r ate : by water not
cuprane, horn silver, and horn lead from muriatic acid by extraordinary.
water extraordinary ; there are several salts containing metal-
lic oxides which are liable to the same change, the oxides
having less affinity for the acid, than water has.
The action of muriatic acid on the combinations of theidiffe- The action of
rent metals and chlorine will, I have little doubt, affurd, when orale
more minutely investigated, explanations of many phenomena, many pheno-
which are not yet well accounted for. Before I conclude, ™e@-
T shall mention only one instance, to which it already appears
tobe applicable. Mr. Proust has observed the decomposition pecomposi-
of calomel by boiling muriatic acid, and its conversion into tion of calo-
corrosive sublimate and running mercury. Nowcalomel being sae
insoluble in muriatic acid, these changes evidently appear to
be owing to the strong attraction of the acid for corrosive
sublimate, which has been already shown to exist,
WII!
136 ON THE SICILIAN CORAL FISHERY.
VIII.
On the Coral Fishery in the Sicilian Seas: by Axrio
Ferrara, M. D.
Mylarum at pontus, Drepanique, et stricta Pelori
Claustra ferunt avidis ramosa corallia nautis.
Flaccomius in Sicelid.
Communicated by the Author.
we po sh oc i AVING for a long time employed myself in the study of
tory worthy the various natural productions, with which the sea that
notice, bathes the Sicilian shores abounds, the coral was the first object
to attract my notice. This beautiful and elegant ornament of
the sea could not fail of deserving first to come under my
The author’s examination. I have been frequently present at the fishing of
sls aa it, near the coast of Sicily: I have contemplated it in the very
bottom of the sea, on its native spot: I have gathered it from
stones, and shells, and other marine substances, recently taken
out of the sea: I have had it worked in my presence :-I have
analysed the several varieties of it : in fine, I have extended my
researches to whatever would give me the least insight into the
nature of this substance, comparing the results of my own
observations with every thing the ancients and moderns have
written on the subject, and consulting in every point the treasures
of natural history, with which the present day has been so
abundantly enriched by the accurate experiments and luminous
theories of the many great men of the last century.
Object of the J have endeavoured in the present memoir to establish a clear
present paper. : : ea ae
and precise notion of the origin, increase, and nature of coral.
This work has been the more pleasing to me, as I flatter myself
Ihave been able not only to confirm by my own observations
what has been already written on the subject by former Philoso-
sophers and Naturalists, but to add some new facts, that may
tend to. elucidate the history of this marine production, which
has at all times as much occupied the researches of naturalists,
as it has engaged the admiratiag of the fair sex, with whom the
beauty of its colour, and brilliancy of its textare, have rendered
it a favourite ornament of dress.
Supposedtobe Theancients, attending only to its external form, conceived
ee the coral to be a plant ; to which from its ramifications it bears
some
ON THE SICILIAN CORAL FISHERY. 137
some resemblance, and named it lithodendron, or stony plant,
on account of its hardness. It was so called by Dioscorides and
Pliny. These authors and their contemporaries did not attempt
to contradict by the most trifling examination, what the poet
Ovid (his head full of transformations) had asserted : that under
the water it was a soft plant, but, immediately on being taken
from the sea, became hard. This opinion prevailed for a long and many
time, and was encouraged in later times by many great natural- ™oderns.
ists. Of this number was the celebrated Cesalpino. .
Our Baccone, who took much pains to investigate the nature paccone’s
of coral, could not divest himself of this idea ; but, gifted as he opinion of it.
was with great sagacity and penetration, not being convinced,
either from his own observations or those of others, that coral
was a mere plant, and still less that it was a stone, he imagined,
_ that the milky juice, which drops from the pores of fresh coral,
was its seed ; which, being dispersed in the sea, is precipitated
and gradually accumulated in a regular form in the capsules
nature provides for it*.
This opinion, tending to alienate naturalists from the belief Count Mar-
of the vegetable nature of coral, was entirely removed by the silli’s.
publication of the valuable and erudite work of the celebrated
conte Marsilli, entitled Storia del Mare ; who, led away by his
imagination, or rather deriving little aid from the state of
natural philosophy at that time, suggested the idea, that the
movable substances at the extremity of the branches were the
octopetalous flowers of the coral, and thus revived the old
opinion.
Tournefort, who, in the pursuit of his favourite study of Embraced by
botany, had remarked the vegetation of stones in the grotto of ee
Antiparos, eagerly adopted this idea ; and was followed by Ray,
Boerhaave, Klein, and many others of that time.
No sooner had naturalists begun again to take up the Supposed tobe
observations of Baccone, than they discovered in the hard sub- 2 Sani ey '
stance of coral a sort of earthy concretion : but this not being ¢ careous lve
sufficient to induce them to expunge it from the list of vege-
table substances, they considered it as a marine plant encrusted
with calcareous earth deposited by the sea. Lehman was of
this opinion, to which the mineralogist Baumer was also much
inclined.
* See Rechescher sur le Corail, and Museo di Fisica. O
! ur
138 ON THE SICILIAN CORAL FISHERY.
FerranteImpe- Our Ferrante Imperato, in his work on natural history (whicir,
OEE like many other works of the ancients, has been almost buried
“the habitation In oblivion, though well deserving our attention from its con-
ofworms. taining the principles of many important truths, which have
since been brought to light), had already supposed, that some of
the species of coral were merely the habitation of marine
This opinion Worms. ‘This opinion had so much of probability, that it has
Sinan always been entertained by naturalists since ; and the discovery
: of the polypi assists to explain on solid principles the true nature
and origin of coral: and on this account the works of Peyssonnel,
Jussieu, Guetard, Trembley, Reaumur, Donati, Ellis, Pallas, ,
Cavolini, Spallanzani, and many others on coral, became so
interesting, Coral is found round nearly all the Mediterranean
islands, Pliny and Dioscorides speak much in praise of that
found in the Sicilian seas* in their time. It is fished for at pre-
sent on every part of the shores of Sicily. iit ea
Places where The Messineze collect a great quantity in those straits, even
oa lane as far as Melazzo ; but the Trapanese, who are chiefly employ-
‘ ed in working the coral, not only fish it in the neighbouring
seas about the Eolian and other islands, bat extend their search
to all the Southern shores as far as Cape Passaro, and beyond
Siracuse, and even to the coast of Barbary. They are obliged
to aceupy so large'an extent of sea; as they cannot fish again
Requires eight OM the samme spot for several years, the re-production of coral
years for its requiring a great length of time, even neatly eight years. I
reprorBienen. have myself collected it on the shores of Catania, and thence as
far as Taormina.
Tha ae The instrument with which the coral is detached from the
used to get it, bottom of the sea has been known a long time. It is composed
of a large wooden cross, having fastened to each of its four —
extremities nets sufficiently capacious to enclose. the coral,
which is broken from its root by a large stone hanging from the
centreof the cross. The instrument is let down by two ropes
from the boats employed in this fishery into the sea, and after
* See Dioscorides, lib. 5 ; Plin. lib. 32. Pliny says, Laudatissimum tn
Gallico sine circa Siovchacas insulas, cé in Siculo civea Heliam, ac Dra-
punum. Some commentators, not finding the name of Helia, have call-
ed it Aeolias; but the true name is Helia, for the island opposite Trapani
was anciently so called, Pliny himself names itin his $d buok Hicronesus.
remaining
ON THE SICILIAN CORAL FISHERY, 139
remaining a sufficient time it is drawn up by a windlass). The «
Trapanese claim the invention of this machine.
From my own observations, and from the most accurate Coral adheres
information I have been able to obtain from the people employ- APR al
ed in this fishery, I am persuaded, that the coral grows indis-
criminately on all hard substances, as rocks, shells, &c.—I
have seen it attached to an earthen vessel, which had at some
time fallen into the sea, and was taken out in my presence. The tts figure and
usual appearance of coral is that of a tree without leaves. It size.
mever grows toa greater height than twelve inches, and is sel-
dom an inch thick. The direction of its branches extends
always forwards from the spot to which the rcot is attached;
therefore when it grows on the.top of a cavern they spread
downwards ; if from a horizontal surface upwards : most com-
monly however the branches extend downwards, which enables"
the nets to enclose it with greater facility when detached by the
stone.
_ It hasbeen constantly remarked, that the broken branches of Branches
coral attach themselves to some hard substances where they eer aie
continue their growih. It is very common to find many substance.
branches of coral, when taken out of the sea, perforated in They are fre-
several parts. There can be no doubt, that this is the work of aoe ge
the lithophagi ; worms which attack even the hardest substances, worms.
for it is well known that they pierce and destroy the hardest
carbonate of lime. The coral (isis nobilis, Linnei) which is pea most
most eagerly sought after, is of a fine red colour. Artists and esteemed.
ladies give it the preference. It improves the charms of a
beautiful face. Naturalists describe all the varieties; two
original colours in coral may be established, white and red, as
.the two extremes, the gradations of shade from the one to the
other producing infinite varieties, among which five principal
may be distinguished.
Ist. The deep red coral resembling in colour miniom. This varieties.
isconsidered as the most perfect sort ; in fact, it is the largest
and most dense, and receives the highest polish. It is com-
monly called the male coral.
2d. Red coral. This is more or less clear, but always less
brilliant than the first variety.
$d. Flesh coloured coral. The ancients call it light red.
4th,
140 ON THE SICILIAN CORAL FISHERY.
Varieties, + 4th. Dull white coral ; by some it is called fawn coloured,
from its resemblance to the colour of the fawn.
5th Clear white coral. All these varieties are found in the
seas round the island, sometimes on the same spot. The first
and second are not so abundant or common as the others.
Appearanceof ‘The extremities of coral, when extracted from the sea, are
era swelled and rounded, resembling juniper berries. Probably
ty these were the berries remarked by Pliny, which he considered
as the fruit of the coral; although in his work he asserts that
they are white and soft under water, and become hard and red
out of it. I am inclined to believe, either, that he wrote from
the reports of others, or that he has mistaken for them the red
Fluid express- globules formed by the artist. These extremities when pressed,
edfromit. sive out a white unctuous fluid resembling milk, which has a
sour taste. It was formerly thought to be the seed and nutri-
tious juice of the coral plant.
Coral hard in The substance of coral is-hard as well in the sea, as when
theseaandred out The red kind is red from the first, and it is a singular cir-
cumstance, that the ancients should have entertained these two
erroneous opinions, which the most simple examination would
Thecentre have falsified. —The central part or axis of the coral is hard, of
__ hardest. a firm solid texture, even, and lamellated ; and hence capable
Cortical part. of taking the finest polish. This is enclosed by a paler coloured
bark of a granulated texture, interspersed with holes in the
The largest form of stars with eight rays. Inthe coral of the largest size
ieces have an : , 5 ae . .
Eofosnitice of Sometimes is found a kind of joint or union between the diffe-
joints. rent pieces of which it is composed,these having the appearance
Its component Of tubes of some length, lying one above the other. In the:
parts. analysis of coral we obtain a small quantity of gelatinous
animal matter, a large proportion of carbonate of linie, and a
The colour ap- little iron. The different colours of this beautiful marine
seen iron, Production seem to depend on the different degrees of oxidation
ofthe iron, and various proportions of it in union with the
Coral formed animal matter. The discovery of polypi gave the clearest idea
by polypi. —_of the origin and growth of coral. These animals, the last in
-the scale of animated nature, form for themselves small nests
sufficiently solid to shelter and protect them. These soft and
delicate animals, surrounded by an element in a constant state of
agitation, and exposed to the attacks of their numerous enemies,
were instructed by nature to form for themselves a covering
capable
ON THE SICILIAN €ORAL FISHERY.
capable of resisting the percussion of the sea, and affording
them a retreat in the moment of danger,
These coralligenous polypi are only a few lines in length, their The polypi
bodies elongate and ramify into eight delicate threadlike described.
branches around the mouth. These are the arms and legs of
the animal, which it can extend and spread out at will to a con-
siderable distance in search of its food. They are analogous to the
horns of the snail. The curious manner of propagation of polypi,
so different from that of other Jarger and more perfect animals,
is well known ; on examining minutely the gelatinous bodies of
these polypi, a great number of grains, or little buds, are dis-
cernible, covering the surface; these elongate themselves,
increase in thickness, diverge and spread in all directions, and
become young polypi. Scarcely are these developed before a
- new series of sprouts appears from their small bodies by the
increase and growth of the small buds on their surface. By
this rapid succession the family is propagated in every direction,
forming as it were a genealogical tree of existing generations.
It is well known how from the soft nature of their bodies these
animals are enabled to unite and engraft with each other in
thesame manner as plants ; and one branch of these animalcule
so engrafted lives and regenerates another. Even one single
animal may detach itself from the family tree, and establish on
another spot a new family with its various branches. While
large animals have bones for the support of the softer parts, and
shell fish are protected by their shells, the coralligenous polypi
make use of a certain proportion of earth to incorporate with
and give firmness to their form.
Immediately as a polypus has fixed itself ona hard body, it
begins to Jay the foundation of its future generation. If you Groweh of the
only take some stones from the bottom of the sea round Sicily, polypi.
you will find on them small branches of red coral, and round
red spots, which are the first depositions of the coralligenous
polypi. In the same way as the bones of the larger animals are
formed by the gradual deposition of the earthy particles sepa-
rated from their food by vessels adapted to this purpose, so. is
the covering of these polypi formed by the carbonate of lime
mixing and enerustating with the gelatinous matter, which is so
abundantly secreted by their delicate bodies, and gradually
incases
142 ON THE SICILIAN CORAL FISHERY.
incases them except the mouth. If a branch of coral newly
gathered is immersed in a vessel full of sea water, these animals
are perceived issuing from the stellated holes, their mouths
gradually appearing first, and then their silklike arms extend,
in this manner putting on the appearance of octopetalous
flowers, by which the ingenious count Marsilli was deceived.
The multiplication of polypi, of which I have treated, ex-
plains admirably the arboraceous form of coral, as also the
increase of the branches detached from the trunk. I have
Black coral# of before mea fine specimen of the antiphates, the black coral of
the ancients. the ancients, in which the extremity of a branch has united
with the principal trunk, and the polypi are seen bedded in it.
From what we have seen, I think the term zoophyte inap-
plicable to coral; it is neither an animal plant, nor a plant
animal: Nor can it be called a zoolite; as it is certainly not a
stony animal. It is with more propriety a polipaio; which, on
account of its form, and to distinguish it from the other analo-
gous works of polypi, might be called polipaio dendroide. In
‘using this nomenclature, we must be careful not to adopt the
false idea, that the polipaio resembles a wasp’s nest; the wasps
may at will leave their nest, but the polipaio is a part of the
animal, from which it cannot be detached. Thus the polipaio
dendroide is an accumulation of ramified polypi, incorporated
with the solid substance, in the same manner as the shell of
some animals and the bones of others. The above erroneous
opinion cannot be entertained by any one, who observes, that
in coral the gelatinous membrane of the polypus is continued
into the solid earthy part, the same as in bones. Herissant has
already pointed out this mistake. .
px ener fr It is to be inferred from the analogy of coral with bone, that,
progressive, aS it does not arrive at once at a state of maturity, but by
; degrees, its hardness must also be progressive. However pro-
aneeash bable this idea may be, it has not been confirmed by expe-
experience. rience. I have particularly remarked the small quantity of
iron obtained in the analysis of the red coral, I have always
found it combined with the gelatinous animal substance in the
state of oxide. Not to extend this paper too much, I shall
The colour of Omit the results of various experiments I have made; but they
coral ascribed have Jed me to conclude, that the ferruginous substance is
a ee phosphate of iron, that is, the oxide of iron united with phos-
5 phoric
Classification
ef coral,
ON THE SICILIAN CORAL FISHERY. 143
phoric acid, which it is well known gives the red colour to the
blood of animals*. The phosphate of iron therefore, which in
animals has the property of giving the lively red colonr to the
blood, and even the vermilion hue to the skin, serves to colour
the solid part of coral, and give it the brilliant sanguineous
tinge.
The first variety, as I have remarked, is esteemed the most Attempt to
perfect ; it is more solid than the other kinds, of a finer and ae ee
more compact texture, and hence takes a higher polish. In texture andco-
the other kinds, in proportion as the bright colour fades, these !ours.
qualities gradually decrease, so that the white sort, which is the
softest and lightest, is very unfit to be wrought, and takes but
a trifling polish. The deficiency in the quantity of phosphate
of iron diminishes the colour, and at the same time decreases
the density of its texture; or perhaps the light texture by its
porosity permits the water to wash away the colouring matter,
and consequently that which would tend to bring it to perfect
maturity.
To this may be attributed the peculiarities of some corals, in’The red parts
which the trunk is red, and the branches white; or the alan ROR
branches red within, and externally white; or the branches
half white and half red, which is often seen in coralligenous
productions; but the red part always proves of firmer texture
than the others.
While naturalists have been employed in investigating the q.atas an or-
origin of coral, and the nature of its growth, each applying it nament
to different purposes; the fair sex, occupied by the natural
desire of pleasing, have been much indebted to the brilliant
colour and fine lustre of this marine production, Coral formed
into beads is worn as an ornament of the neck and arms; and
there is no doubt, that’ the lively colour of coral gives addi-
tional grace toa fine face and beautiful complexion, which can- ;, some re-
not be obtained by the use of the precious stones, so that spects superior
these can only be considered as ornaments of luxury and show. “Se
The ladies who are always led away by fashion, because they
consider it as depending on the existing taste of the other sex,
laid aside this beautiful ornament, to load themselves with
' * "This is at least highly questionable. See Journal, p. $1, of the pre-
sent volume, and p. 48 of the preceding. C.
jewels
144,
Amber lately
become fash-
ionable,
Coral superior.
Method of
working coral.
Uses to which
it has been ap-
plied.
Superstitions
respecting it.
ON THE SICILIAN CORAL FISHERY,
jewels brought from distant countries. Thus coral gave place
to other ornaments, the rage of pleasing being only gratified
by variety. Works of Amber have latterly obtained a very
high estimation from the softness of its substance and its trans-
parency*,
This substance, which for a time was in high repute, and
which the discovery of the precious stones had almost thrown
into oblivion, has of late, by the accustomed versatility of ca-
pricious fashion, recovered its former value, and has rivalled in
price even the ornaments composed of jewels.
When the value of female ornaments shall depend no longer
on the price or scarcity, but on the effect they produce on the
complexion, all will yield to the natural beauty of coral. Most
certainly Galatea, emerging from the ocean, would select from
the numerous offerings of the nymphs the lucid branches of the
coral to adorn herself with, which would alone assimilate with
the roundness of her lips, and with the vermilion of her
cheeks.
The working of coral consists in removing the outer bark,
and exposing the interior solid and highly coloured part, which
takes a fine polish. ‘The coarse part of the bark being removed
by the file, it is rubbed with tripoli powder, and lastly, with
a metallic earth, which gives the polish. Some bring it to the
finest polish imaginable by the use of the oxide of tin.
The ancients ornamented their swords, bucklers, and hel-
mets with coral; this custom is still in vogue in some part of
Asia, where coral is as much esteemed as in the time of Pliny.
The soothsayers and priests of that age attributed many mystic
properties to it; hence they were in the habit of wearing coral,
as well from religious motives, as from regard to its beauty,
Paracelsus recommends it to be worn round the necks of in-
fants, as an admirable preservative against fitst, sorcery,
charms, and even against poison. Many other follies of that
man are still prevalent, and of great credit with the common
people; and it is very usual in the inland parts of Sicily, to see
* See Memor. sull Ambra di Sicilia, 8vo, Pal. 1801. Written by my
brother, ab Francesco Ferrara, profes, in the univers, of Catania.
f The negroes in the West Indies say, that the colour of coral is
affected by the state of health of the wearer, it becoming paler in
disease,
children
JAMAIEA DOGWOOD, 1435
children wearing amulets of coral round the neck for the above
‘purpose. In the cities itis worn by many in the shape of a
horn, as a protection against the influence of evil eyes. It
was éven believed, that coral would drive away devils and evil
spirits, hence perhaps arose the custom of making crowns of
it. Nor have the medicinal properties of coral been less exag-
‘gerated, as may be sufficiently seen in the writings of Pliny
and Dioscorides. It certainly may be considered as an absor- ’
bent, it is used in dentifrice powder, in the Alkermes for indi-
gestion, and in the Troches of Carabe.
The Trapanese appear to have been the first who worked the First wrought
coral, being induced thereto by the great quantity of it found by the Trapa-
in their seas. It is asserted, that Antonio Ciminello, a Trapa- piss
nese, was the first who discovered the art of engraving coral*, Hngraved.
In the time of king Alphonso the coral fishery was so assi-
duously, and so advantageously pursued by the Trapanese, that
the ministers of that king proposed to subject the fishery to a
taxt. In the last century, when it was again proposed, instead
of a tax, which probably would have ruined this branch of
industry, king Ferdinand instituted some very useful regula-
tions in favour of it.
Beside forming necklaces and bracelets, the Trapanese have
the art of engraving it in the same manner as they do amber
and shells, and most certainly many of these works display
great spirit, boldness, and grace in the execution, talents natu-
ral to the genius of the Sicilian nation.
IX.
On the medical Effects of the Bark of the Piscidia Erythryna of
Linneus, or Jamaica Dogwood. Ina letter from WiLL1aM
Hamitton, Esq.
To Mr. Nicholson.
Nevis, the 20th of July, 1812. -
SIR,
OUR readers may perhaps have accidentally heard of the Bark of the
remarkable effects produced upon fish, by mixing a ad eave
for poisoning:
* Orlandini Descrizione di Trapani. fish.
+ Capit: & Costituz. del Regno. See also, Muta capit: 49 del Re
Giacomo G. 1,
Vor. XXXII, No. 152.~Ocrozer, 1812. L strong *
146
Its effects tried
by the author
on himself.
A tincture the
best prepara-
tions
Mode of pre-
sparing it.
One ofits ace
tive principles
resinous.
Its dose and
yestects,
Fxternally
cures tooth-
ache.
JAMAICA DOGWOOD.
strong infusion of the bark of the roots of a tree, well knowit
by the name of the Jamaica Dogwood, with the waters of the
ocean, This process, well known to the planters and others
here by the name of fish poisoning, has been too frequently
described to render any particular account from me necessary.
However, the effects upon fish appeared to me so singular,
that I was led to try how it would act upon the human subject ;
and as, from the very strong and general prejudice entertained
against this plant, I was not likely to succeed in persuading
others to submit to my trial of its effects upon them, I was ne-
cessarily reduced to make trial of it in my own person.
To detail the various experiments which I have made, with
the view of ascertaining whether this plant possessed any, arid
what medical virtues, would be superfluous here ; and I shall
only observe, that I have at length discovered the tincture to be
the least exceptionable form of exhibition. This is prepared
by macerating an ounce of the dried bark of the root, in fl3vj
of rectrified spirit and | fj of water, or which will amount to
the same thing, in AZxij of proof spirit, for three days, and
straining ; when a tincture will be obtained of a fine clear
topaz colour, somewhat resembling that of fine old Madeira
Wine; when this tincture drops on any substance, a white re=
sinous film is found remaining after the : anit has evaporated,
and a milky fluid is formed by the admixture of water ; thereby
showing, that a resinous substance is one of the active consti-
tuents of the bark. The smell and taste of this are not dis«
‘agreeable ; ; and I find, that from Ai) to ‘Alziv takenin a flask
of water at bedtime, produce any siatheiaie sensation of
warmth in the stomach, quickly succeeded by an univefsal
glow on the surface, together with ‘a profuse diaphoresis, and
followed by an agreeable, tranquil, and refreshing’sleep ; 'with-
out occasioning any of those distressing sensations, which
opiates so frequently produce.
In odontalgia from a carious tooth, where the nerve is ex-
posed, a little of this tincture introduced ‘into the cavity, pro-
duces instant and ‘most commonly permanent relief. Upon
the whole, I regard it aswell deserving of farther research, as
_ it promises to ‘add a very valuable médicihe’ to the class of
fom of the
anodynes.
Mr. Carlisle, of Soho Square, has been furnished with some
of
ON THE UNCOMBINED ALKALI IN ANIMAL FLUIDS. 147
ef the dried bark of this plant, which is the piscidia erythryna bark sent to
of Linnaeus, and grows most abundantly in some parts of this oe eee
island. Before I conclude I cannot help remarking, that this
is one of the deciduous plants, no leaves existing on it during eas de-
the period of flowering, which is in the month of April ;
I hee the honour to remain,
In extreme haste, your’s truly,
WILLIAM HAMILTON.
This shrub is fhe icthyomatheia of Brown—see his history Mentioned by
of Jamaica. Brown in the same place notices a shrub gtowing B°OW™-
at Surinam, the leaves and smaller branches of which are em- Inquiry after
ployed for a similar purpose, with the bark of the, root of the aie leone asia
Dogwood. He calls it a Cytisus, which I strongly suspect to be
- erroneous, Some of your readers can perhaps favour me with
the real name, habitat, and other particulars of this plant.
: 2 ue 4
X.
A Correspondence Letween x. Bostock and Dr. Marcer, on
the subject of the uncombined Alkali in the Animal fluids.
To Mr. Nicholson.
Sir,
NHE attention which I have for some time paid to the Cosieovisip™
subject of animal chemistry, caused me to read with on the alkali
much interest the controversy, which was carried on through Si a
the medium of your journal, between Dr. Pearson and Dr.
Marcet, respecting the nature of the uncombined alkali in the
serum of the blood. I was induced to make a considerable First supposed
number of experiments upon the subject, the result of which '° > 2 iii
had led me to. decide in favour of Dr. Pearson’s opinion ; but
having communicated. my doubts to Dr. Marcet, he repeated
and extended his former experiments in such a manneras, I
think, firmly to establish the fact, that the alkali is soda. The But since
detail of these experiments, as contained in the following letter proved to be
ef Dr, Marcet to me, I have his consent to transmit to you for nas
L2 publi«
i}
;
* ~
148 ON THE UNCOMBINED ALKALI IN ANIMAL FLUIDS.
publication ; and, I believe, you will agree with me in the
opinion, that they must entirely set the question at rest.
" I am, Sir, |
Your obedient Servant,
_ J. BOSTOCK.
Knotshole Bank, near Liverpool,
Aug. 22d, 1812.
*
, Dr. Marcet to Dr. Bostock.
‘© Londo, August the 19th, 1812.
« My Dear Frienp,
Controversy «* T feel much indebted to you for the remarks you have
Ll at te made, and the doubts you have expressed, in some of your
@uids. last letters to me, respecting the nature of the uncombined
alkali in the incinerated salts of serum; they have in-
duced me to reconsider the question, and to add to my former
inquiry on that head, a few new results, which, I flatter myself,
will remove every shadow of doubt, which may remain on
your mind in that respect.
Why no new ** In my reply to Dr. Pearson, in March last, I abstained
eae purposely from bringing forward any new’ data, because the
last letter. | Chief object of that letter was to vindicate former statements
and inferences; and to show, that there had not been, as was
argued by my opponent, any blunder in the mode of reasoning
by which I arrived at my conclusions. Indeed, it appeared to
me hardly necessary to push the inquiry any farther ; and I
must own that, from the manner in which Dr. Pearson had
thought proper to carry on the controversy, in his two letters
on thesubject*, I should have felt great reluctance to resume
the discussion, had it not been for your interference.
Source of Dr, “© Your objection, or sather your scepticism, arose from your
Bostock’s- having found in a mass of salts from serum, (by the suc-
ee the cessive agency of acetic acid, alcohol, and tartaric acid,) such
quantities of potash, as appeared to you to show, that the
uncombined alkali was potash, and not soda ; and you were
farther confirmed in this belief by obsérving, that the alka-
os
* See this Journal for February and May last.
line
ON THE UNCOMBINED 4&KALI IN ANIMAL FLUIDS. 149
line residue obtained by heating the acetat to_redness, was
deliquescent. You will see, however, by the following
statements, that you were mistaken in your inference ; and
you will, I make no doubt, admit, that the potash, which
you foundin the alcoholic solution, must have been in the ,
state of muriat; and that the deliquescent quality -of the
alkaline residue must have arisen from your acetat having
been but imperfectly decomposed, on account of the too low
degree of ignition to which you had exposed it, and perhaps-
also (as you have since yourself observed) in consequence of ,
the presence of muriatic salts, But your experiments appear Large ptopor-
toshow, that the proportion which the muriat of potash in een
the blood bears to the muriat of soda, is greater than I had at in the blood,
first imagined ; and that we had both underrated the power
of alcohol to dissolve muriat of potash. —
“< As tothe point at issue, however, namely, the nature of The uncom.
the uncombined alkali, in the incinerated salts of blood, the si aie ae
experiments upon which I think myself warranted to repeat,
with increased confidence, my former opinion, that . the
alkali is soda, and not potash, were conducted in the following
manner. ;
© After evaporating some human serum to siccity, incine- Experiments
rating the residue, dissolving in water the soluble saline sub- Proving this.
stances contained in the incinerated mass, filtering this solu-
tion, and evaporating it again, the alkaline mass of salts thus
obtained was treated with acetic acid, and afterwards digested ©
-with 5 or 6 times its weight of alcohol of the specific gravity
of 0'S15. The highly deliquescent residue, deposited by the
evaporation of the filtered alcoholic solution, was then made
red hot in a platina crucible, and kept for a few minutes in a
state of igneous fusion. A carbonaceous «lkaline mass re-
mained in the crucible, which, after being exposed to the air
for 48 hours, in a room without fire, and in damp though
warm weather, did not exhibit the least vestige of deliquescence.
This mass, the quantity of which amounted to 4 or 5 grains,
being dissolved ina little water, was divided into four portions ;
a,b,c,d
“« The portion a, being examined by re-agents, exhibited the
following properties.
*© 1, Itcontained abundance of muriatic acid,
450
aoe | + ‘a, \ al P . = 4 ’ Avy e yrs a ¢
ON THE UNCOMBINED ALKALI IN ANIMAL FLUIDS.
“© 2: When suffered to evaporate spontaneously ina glass
capsule, it Jeft, at the end of 12 hours, a dry efflorescent cry-
stalline substance, which consisted principally of feathery
crystals, amongst which were discetned groups of rectangular
plates, anda few minute cubes. _
“<¢ 3. The presence of potash in this crystalline mass was
made obvious, both by the tartaric acid, and by oxymuriat of
platina, though not so much so by the latter of these tests.
The portion J, was saturated with sulpharic acid, and
submitted to spontaneous evaporation. The result was a rim
of confused crystals, surrounding a group of regular efflorescent
prisms of glauber, being (at least some of them) terminated
by distinct dihedral summits, and having sufficient magnitude
to be identified by the naked eye, even at the distance of a
few yards ; they were made to crystallize over and over again,
always with the same result ; but in some of these crystalliza~
tions, a few crystals of ae of potash also appeared, the form
of which was not equivocal. !
The portion c, being treated with nitric acid, yielded by
evaporation great numbers of rhomboidal crystals, ‘perfectly
distinct to the naked eye, and amongst which no oo at all
resembling that of nitre, could be detected.
** The portion d, being treated with oxymuriat of platina,
the usual crystalline appearance of potash-muriat of platina
took place immediately ; but by slow spontaneous evaporation,
other and more abundant needle-shaped crystals of soda-muriat
of platina made their appearance.
«© My conclusion therefore, (which I hope will now also be
your's) is precisely as before ; namely, that the potash which
éxists in the animal fluids, is in the state of muriat, and that the
whole of the uncombined alkali is soda; and as it isa known
fact, that muriat of potash is id some degree solable in alcohol;
the circumstance which led you into error is readily explained.
“** Thave only farther to add, that the fact, which I have en-
deavoured to establish by a specific inquiry, ought to have been
inferred from principle ; for it is well known that potash ‘has
a stronger attraction for the muriatic acid than soda; and in-
deed I understand that itis a common pee in some manu-
Bice v8 ae td Ws iia
CULTURE AND PREPARATION OF HEMP. 151.
factories, to obtain soda by the action of potash-lye on muriat
of soda.
\ :
** Believe me, ever, &c. &c.
““ ALEXANDER MARCET.
** P. S. Since the above was written, I have, in consequence Soda from Bult
of your suggestion that the blood of Graminivorons animals Birenesn ii
might perhaps yield potash instead of soda, onaccount of their liv-
ing, exclusively upon vegetable food, examined bullock’s blood,
with a view to ascertain this circumstance ; and as there was
no difficulty in procuring any quantity of that blood, I had some
gallons evaporated, from which I procured some ounces of salts,
in order to satisfy those who think that nothing certaincan be
inferred from experiments upon a small scale. However, the
results were precisely similar, except that the crystals of sulphat
and nitrat of soda, obtained by the processes above detailed,
were of much Jarger dimensions than in any of my former
experiments.”
XI.
On the Culture and Preparations of Hemp in Dorsetshire, and
on the Growth of Sea Cale: ly H. B. Way, Esa.*
Dear Sir,
S you informed me, when you were lately in Dorsetshire, Information
that the Society of Arts, &c. were anxious to obtain in- FABEROR.
formation concerning the culture and preparation of hemp in rable.
this neighbourhood, I am induced to send, you some account
thereof.
I fear my memorandums on the subject will not be worthy
the notice of the society, and I should scarcely have ventured
to have put pen topaper upon it, if I bad not uniformly found
that the persons who are concerned in the growth and ma-
-Nagement of that article are shy of giving information. If
what I have sent should induce persons equal to the task, In what parte
to make the needful inquiries in this county, Somerset, Suffolk, of England ©
* Trans.of the Soc. of Arts, vol. KX XI, p. 63.
152 CULTURE AND PREPARATION OF HEMP.
chiefly cultiva- and Norfolk, (which I believe to be the parts of England
ted, where hemp is most cultivated,) and make the culture more
generally known that it now seems to be, I shall be ‘much gra-
tified. I hope, if you again visit this neighbourhood, to show
‘Wheat after it you a very fine crop of wheat on the field where you last year
ed ma- saw the persons employed in collecting the male hemp; also
another large field of exceeding good wheat, that produced
hemp last year, neither of which have~had any fresh manure
upon them, since the hemp was taken from the fields. I haye
Sea cale valu. 2dded some observations on the growth of Sea Cale: this
or USlpiadiaa useful vegetable, growing naturally on some of the cliffs
tivate, “near Bridport Harbour, and being one of the most valuable
esculent plants that I know, I have found the culture of it
in the kitchen garden more easy to manage than has toed ge-
nerally supposed.
I have sent different specimens of the seed, and some of the
natural soi], for imspection :
And remain, Dear Sir,
Your friend and obdient Servant,
H. B. WAY.
Bridport Harbour, March 1st, 1811.
Account of the Culture and Preparation of Hemp in Dor-
setshire.
Preparation of Hempis usually sown about the 15th of May, on the best
a ay for arable land, on which about twenty cart-load of good rotten
dung has been spread, say about aton tothe load. This is
well ploughed in, and the ground well ploughed two or three
times, and well dragged and harrowed, to get the soil as fine
' as possible, and about two bushels of seed, or two and a half,
Quantity of sown to the acre. What produces no seed, called by some
seed. male or summer hemp, and by others cinner hemp, is drawn
ee the ‘about five or six weeks after the plant comes up. It is at that
vee" time in blossom. When drawn, it is tied up in bundles, and
carried to some meadow land, and there spread to ripen : when
| ripe and dry, it is bundled and stacked. What stands for seed
The fema'e. 1.45 no flower that can be discovered 3 it is the female hemp, and
is generally ripe early in September ; whenit is drawn, bundled
up,
CULTURE AND PREPARATION OF HEMP. 153
up, and stowed up in the field, for the seed to dry and harden,
when it is thrashed out in the fields. Most commonly in
Dorset the seed is sold onthe spot, at from 2s. 6d. to 7s. per Seed.
bushel; an acre of hemp produces eighteen or twenty bush-
els. In Somerset they have sometimes thirty bushels of seed
tothe acre. In the sowing season I have known 21s. per
bushel paid for seed. When thrashed the hemp is carried to The hemp
the meadows, and spread to ripen as the other, and stacked thrashed
in the same way, to prepare it for sale; it is sent to the
houses of the poor in the parishes round which it is raised,
to be what is called scaled ; that is, each saparate stalk of 2"d scaled.
hemp is broken in the hand, and the hemp, which is the
outside rind or bark, is stripped off ; in which state it is sent
to market. The scaling is the employment of old men, \
- women, and children, and of the whole ef the Jabouring
family in the evening, as in winter they make but poor wages
of it; and one principal inducement for them to do it is,
that the woody parts of the hemp make them a fire, but it
soon burns out. Complaints are made of a great deal of the Complaints
4 4 respecting
hemp being often wasted from improper management, and this,
want of care in the scaling of it, At the Comptons and
Bradford, a good deal more hemp would be raised if they
could get it scaled, which they find much difficulty in doing ;
and if it were possible to construct a mill that would swingle A mill for the
it at a moderate expense, on some such plan as the flax Purpose desi-
swingling mills, and to afford some encouragement to the Tha
erecting them, as well as flax swingling mills, it would encou-
rage the growth of both articles materially. An acre of hemp produce per
in a goodseason will produce 14, 16, or 18 weights, of 32]b, acre.
tothe weight, in Dorsetshire; in Somersetshire they reckon
_ their weight two pounds less, and they sometimes get as much
as 35 weights to theacre. The price of the weight of hemp
is from 16s, to 20s. per weight. The rotation of crops as
follow : Rotation of
On ground well manured, Hemp. | eke
Wheat.
Barley or Oats.
Clover with the above.
Wheat,
154 CULTURE AND PREPARATION OF HEMP,
Barley or Oats.
Ground well manured, _ Hemp.
But sometimes they dress the ground well for hemp every
third year. The quantity of hemp sown in Dorset, is very
Hemp and flax trifling in comparison to what is sown in Somerset. In the
clad a former it is chiefly confined to eight or nine parishes; whereas
Misterton, Crewkerne, Hinton St. George, Lopen, Seaving-
tons, Ilminster, Stecklinch, Donyatt, Kingstone, Shipton,
Beauchamp, Barington, South Petherton, Martock, Norton,
Chiselborough, Stoke-under-Ham, Montacute, Odcombe, the
Chinniocks, the Cokers, the Comptons, Bradford, and a great
many other parishes. Mr. Emanuel Pester, of Preston, : near
Yeovil, is in the middle of the hemp and flax county; and he
can doubtless cbtain and give every information that may be
wished on the subject, being so extensively engaged in agricul-
tural pursuits himself, and so competent to give that sort of
Bounty for- information wanted, A bounty of 3d. per stone on hemp, and
mri given on 4d, per stone on flax, was for many years given by government,
but is now discontinued; it was paid by the clerk of the peace
for the counties, and as the late,Mr. Wallace managed that for
the county of Dorset uncommonly well, it is most probable,
that.a very correct return for the county of Dorset could be
obtained fromthe office of the clerk of the peace for . this
county, of the quantity raised each year of both articles, dur-
“ing the .continuance of the bounty; also from Devon and
Somerset, similar. returns coull be got. ‘There are large quan-
tities of hemp:raised in Suffolk, the writer thinks, near St.
Very fine linen Edmund's-Bury .and. Stow-market, in that county. He has
‘oe been told they,make linen so, fine of hemp, as to be worth 5s.
and 6s..per yard, and used for shirts in preference to Irish,
being considered..much more durable and better, so much so,
as.to induce the Irish to,imitate the fabric, and stamp the cloth,
Suffolk hemp. It is also raised in Norfolk, in the neighbour-
hood of Lynn and Wisbeach, but, it must be watered and pre-
pared in some other way; indeed he is convinced that all the
hemp imported from the Baltic is prepared differently from the
mode used in, Dorset and Somerset, and must have been swin-
gled before it was sent to the different ports it was shipped at
Bounty should for this country. The giving the former bounty on the growth,
gud
very large quantities are raised in Somerset, in the parishes of -
———E
GULTURE AND PREPARATION OF HEMP. 155
and increasing it on hemp and flax, would encourage the be on the pro
growth ; but if given on the number of acres sown, the grower, 1 ae
as his ground would be in high order for a crop of turnips and land.
wheat after, might be careless about his crop of hemp, as the
bounty, to be worth notice, must be worth more than the value
of the seed in common years and the labour of sowing.
Hemp in this county and the next is never sown in new Flax sown on
ground fresh broke up, but flax always by choice, when fresh "ew ground,
ground can be got. Mr. John Pitfield is going to break up is gh OR
great part of the West Clift at Bridport Harbour, and sow it
with flax this season. The writer, while on the subject of
hemp, ‘is led to mention, that when travelling in the year
1792, in the province of Massachusets, near Boston, in North Hemp sown
America, he was assured that considerable quantities of hemp oe
were raised in the township of Sunberry, about ten miles from
Boston ; and that it was always raised on the same ground
every year, no other crop being sown in their hemp lands, and
that it was manured every year, at the rate of about ten tons of
manure to the acre of hemp. Respecting seed, he cannot
fearn that there is any for sale at Bridport, with the buyers who
purchase it up for the growers at the hemp harvest, and he
expects that very little can be got from the growers round here.
Somersetsbire i is a more likely place to get it, as he has known
‘some of the hemp farmers to have upwards of a hundred‘acres
of hemp i in One season. Round this they generally are only in
a small ‘way. A change of henyp- seed is much wanted in Chanewudiate
as Somerset | and Dorset. Trials have been ‘made two or three wanted,
times to ‘get it from Russia, but it is not possible to get néw
$eed from the interior early enough in the fall at the shipping
‘ports, and : some old seed which has been shipped has not’an-
swered the purpose ; ; if new could have been got, it would as
‘generally have been» used for a change, as the new Riga barrel
flax seed is by the flax-growers. As the seed sown in Russia Suggestions _
“was considered a good sample, and its appearance ‘much liked, cadearyeres: 2
‘possibly i it® might, ata future period, be obtained’ in the fall
‘from Odessa, or some other port on the Black Sea; as it ‘is
“understood that a good deal of hemp shipped at Riga and ‘St.
Petersburgh | grows much nearer to the Black Sea than the Bal-
“tic 5 or ‘ possibly the seed of the ‘Italian hemp raised in the
neighbourhood of Bologna, or that of America, might be
obtained
156
A previous
crop of
vetches.
Hemp alter-
nated with
turnips,
Manure for
hemp.
CULTURE AND PREPARATION OF HEMP.
obtained. in time to answer. Perhaps: tares, called by scme
vetches, might be cleared from the ground early enough for
manuring and sowing the ensuing crop of hemp, and vetches
might make it worth the farmer’s attention; to this an objece
tion was stated, which I do not just now remember. On talk-
ing with the gentleman before-mentioned, and stating the
American practice, with what had passed on it with my neigh-
bours, he said, he had long been persuaded, that it was a good
practice ; and. that, he had the last season a,very gocd crop of
hemp en a-piece of ground that had hemp the year before, and
that he did not let,the hemp stand for seed, but had it all. down
at the usual time for drawing.the summer or male hemp, and
the ground immediately sown with turnips, which were fed off
with sheep, and the ground then slightly manured, and hemp
sown again at the proper season ; and that he had then, October
27, 1808, a piece of turnips after his hemp, which were
worth 6/. per acre. It is to be observed, that the acre here
meant is the British acre of one hundred square poles, three
hundred and four square yards each. The manure mostly used
for hemp is good rotten stable dung, which is much preferred
to any other, though lime is frequently used; but manufactu-
rers pretend to assert, (with what foundation I cannot say),
that they can distinguish a material difference in the quality of
the hemp, where lime has been used instead of dung; as from
lime they say hemp is more harsh and brittle, and not of such a
soft silky quality as where dung has been used. The writer has
endeavoured to throw together every thing that occurs to him
on the subject of the culture of hemp, which, from being born
and residing great part of his life in a part of the county where
it has been extensively cultivated for ages, he has been able to
collect ; but where it is not very easy to obtain direct informa-
tion, as both the growers and manufacturers are very shy of
giving any, under an idea that it might injure their own inte-
rest by assisting to extend the culture to other countries. He
believes that his statement may be depended upon; but he is
no farmer, and therefore the loose hints thrown together here
on the subject may not be so clearly and satisfactorily explained
as he could wish; but if they in the smallest degree assist in
encouraging the growth of an article so essential to the welfare
and
CULTURE Of SEA CALE.” }
{
and prosperity of the kingdom, it will afford him the most
heartfelt pleasure.
MDP WwaAY,
Account of the Culture of Sea-Cale, or Sea- Kale.
The mode which I consider the best forthe culture of sea_ Cultivation of
-cale-is to draw lines in a very dry soil and dry situation, irene
‘on ground with a southern aspect, about two feet one way by
- about eighteen inches the other, and where the lines cross, te
“put in three or four good perfect seeds in a square or triangle,
about three inches apart. This may be done any time in No-
“vember or December in open weather; and it will require
‘noother care afterwards but keeping the ground clear from
weeds till the autumn of the following year, when all the plants
but one of the finest in each square may be taken up, which if
»wanted will serve to form other beds set the same distance
apart. The ground in the intervals of the plants should be
dug in the spring and fall of the year, taking care not to in-
jure the plants. The leaves should be left on the plants till
they fall off naturally, which will not in general be sooner than
the latterend of November. In the autumn of the second year,
‘the same attention should be paid to the plants, and to remove
the dead leaves.
In the third year, about the middle or latter end of Novem- pjanching.
ber, when the leaves had been cleared away, and the ground
-dug, each plant should be covered over cluse with a tub, pan, a
heap of small stones,, coarse cinders, or coarse bark, raised
about ten or twelve inches over the crown of each plant, and
from about the latter end of February to the latter end of
March, the plants will be very fine and fit for use. I prefer
that which has been blanched with ovr round sea-gravel, about
the size of large peas or beans, to any other mode whatever.
The plants should be cut but once ina year, as cutting them
oftener weakens and lessens the size of the plants. If it is
not desired to have the plants large, they may be blanched and
cut a year sooner,
I have sent a specimen of the sandy soil in which it grows Sandy soil best
naturally here, as I think the generality of gardeners are too for it.
careful, and manure the ground too highly for it, In the
month
158 ON THE PERFUMED CHERRY-
month of April last, after dutting my plants, I covered the
ground all over, at least six inches above the crown of the
plants, with this earth, they soon shot up through it, and ne-
ver looked finer, or produced a larger quantity of good seed
than that year.
Tam thus particular in order to show, that this vegetable
will succeed as well, if not better, in poor ground than in rich ;
provided the soil be dry, and care taken in the management,
I speak from the long experience, having been well acquainted
with the management of this valuable plant from my youth.
When I cut the sea-cale for use, I immediately draw up thé.
should be co- earth with a trowel, so as comple’ely to cover the whole of the
vered when : ; 2
eae. plant; this I fancy makes them grow more luxuriantly. Thié
plant, if properly managed, is superior to asparagus, and if more
is cut than wanted for immediate use, it will keep for some
days in a panof cold water, but of course it cannot be better
than when recently cut. It precedes the use of asparagusy
being ready for the table in February and March. ;
H.B.i WAY.
XII.
On the perfumed cherry, Prunus mahaleb: ly Mr. ToLiarp,
senior*,
The perfumed HE perfumed cherry is a pleasing tree far shrubberies.
shel Its flowers are white, and diffuse a very pleasant smell.
It rises as high as twenty feet, grows in poor land, and appears:
Laila Fred particularly suited to a chalky soil. In this respect it is a
chalky land, Valuable tree, as scarcely any other thrives in a soil of this kind ;
except the Scotch fir, pinus sylvestris, and the salix caprea.
The wood of the prunus mahaleb is smooth, close grained, takes
a good polish, and is useful in turnery, cabinet-making, &c.
sey ot he Any sort of cherry may be grafted with success on a stock of
cherries. the prunus mahaleb, It is propagated by seed, which is sown
Seed sown in inthe course of the autumn. It thrivesso much in chalky
ee. and marly soils, that extensive plantations of it have been made,
ince this property has been discovered. |
and its woo
wery useful,
* Sonnini’s Bib, Phys, Econ, Feb, 1810, p, 82.
Notice
DISEASES OF TREES HEREDITARY. 159
Notice from a Work of Monsieur Levieur, on the hereditary
Diseases of Fruit Trees: ly the Right Hon. Sir Josern.
Banks, Bart. K. B. P. R. S. &c.*
LELIEUR, a French gentleman who holds the office
-®@ of Administrator of the Parks and Gardens of the
crown, has lately published a book on the diseases of Fruit
Trees.
In this he asserts, that the disease called in French le blanc, Heredita
or le meunier, which shows itself by a mealy whiteness on the diseases in the
leaves of the peach tree, or on the fruit itself in blotches, P&ch tree.
that destroy the flavour, is an hereditary disease: that plants
raised from the kernels of trees subject to this disease, will
produce plants in like manner infected, and which will com-
municate the disease to grafts taken from sound trees inserted
inthem; and that grafts from diseased trees will certainly. be
diseased, although taken from branches that -are quite free
from it.
He attributes the samé hereditary continuance to the gumt, Gum also heres
‘a disease more mischievous possibly than any other, to our ditary.
grafted and budded stone fruits ; and he is of opinion, that this
disease also may be entirely avoided, by grafting froin trees that
never have been subject to its attacks.
The importance of these facts to the interests of horticulture,
will, it is hoped, justify the writer for offering this short account
of them to the society, though they are taken from the Moniteur
of the 7th December, 1811, the book not having been yet
brought into this country.
The mealy disease, he says, is certainly not contagious, and the mews
he instances a fruit-wall at Versazlles, on which are many disease net__
eurious ; peach trees, some of which are much damaged by it, Com*siovs.
while others are, re intirely free from it.
4:
a a ie
XI.
SCIENTIFIC NEWS.
Medical and Chemical Lectures.
N Monday, October 5th, a course of lectures on physic Medical and
¥-and chemistry will’ re-commence.in George Street, elas lee:
’ Hanover Square, at the usual morning hours, viz..the Thera-
* Trans, of the Hort, Soe, Vol.i: App p. 87.
160 SCIBNTIFIG NEWS.
peutics at eight, the practice of physic at half after eight, and
the chemistry at a quarter after nine. By George Pearson,
M.D. F.R. S. Senior physician to St. George’s ee of
the College of Physicians, &c.
Clinical lectures are given as usual on the leg ‘of St.
George’s Hospital every Saturday morning at nine o'clock.
Lectures on Surgery, Physiology, and Pathology.
ipa ten Mr. A. Carlisle, F. R. S. professor of anatomy in the royal
ology, and pa- academy, and surgeon to the Westminster hospital, will begin
ealeey: his course of lectures on the art and practice of surgery, and
the sciences connected therewith, on Monday, October the
12th, at half after eight, P. M., at his house in Soho Square.
The introductory discourse is open to all professional stu-
dents, and the subject to be continued on Mondays, Wednes-
days, and Fridays, at the same hours.
The diseases and accidents allotted to the province of surgery
will be amply treated of, and illustrated by cases from the lec-
turer’s experience. A compendious view of the animal eco-
nomy will be adduced to illustrate the several processes of dis-.
ease, and of recovery.
The operations of surgery, and the anatomy of the affected
parts, are to be demonstrated.
eae ll
Surrey Institution.
Lecturesatthe We understand the following arrangements have been made
Surrey Institu- for lectures at the Surrey Institution, in the ensuing season ;
hoe. Mr, CoreripcGe on the Belles Lettres, to commence on Tues-
day, the 3d of November, and to be continued on each suc-
ceeding Tuesday; Mr. Mason Goon on the philosophy of
physics, to commence on Friday, the 20th of November, and
to be continued on each succeeding Friday ; and Dr. Crotcr
on music, to commence early in 1813.
\ London Hospital.
Practice of Dr. Buxton’s autumnal course of lectures on the practice of
physic, medicine will be commenced on Thursday morning, the sa of
October, at 11 o’clock.
‘ Nicholson's Philos. Sournat Tol XAQME. PM p ar}
On the apparent figure of Stars, &c.
Fig.2, Fig. 3. fig.4. Fig.5. Fig.6.
BY D a a c
cC [
eS
6 r,f
m4
Refraction of light .
| A
JOURNAL
; OF
NATURAL PHILOSOPHY, CHEMISTRY,
' , AND
THE ARTS.
NOVEMBER, 1812.
ARTICLE I.
«4 Continuation of Experiments on the soniferous Vibrations of
the Gasses, €Sc. by Messrs. Kensy and Murricx.
To William Nicholson, Esq.
SIR,
ry NHE following experiments, on the musical sounds of the
4. gasses, were performed with new apparatus, similar to that
which I described in a preceding communication to the Philo-
sophical Journal, vol. XXVII, p. 269. To those who may be
disposed to construct apparatus for the same purpose, a state-
ment of its dimensions will not be unacceptable. Such, how-
ever, as would possess it without the trouble of fitting it up
themselves, may procure it of Mr. Bancks, 441, Strand.
The bellows are made of three small pieces of mahogany, Beliows. _
each six inches long, three wide, and three tenths of an inch in
thickness. They are connected by folds of thin leather, glued
round their edges. The requisite pressure on the bellows is
given by a spring of brass wire. A kind of fusee was added, to
equalize the blast ; something like a contrivance for the same-
purpose in Mr. Liston’s perfect organ :—on trial it was found
in this case, to be of no advantage.
Vou. XXXIIL, No. 153.—Novemser, 1812. _M The
162 ON THE SONIFEROUS VIBRATIONS OF THE GASSES.
ine. The organ-pipe employed is of the kind called the stopped
diapason: its width is 0°57 of an inch, depth 6°71, and its length,
without the plug by which it is tuned, 5°15 ;—-the thickness
Its pitch. of its sides 0:15, and the width of the mouth 01:16. When
tuned a minor tone above one of Hawkins’s new C tuning-
forks, the length of the vibrating column of air was found to
be 4'1 inches ; the barometer being at 29°60, and F. thermo-
meter at 65°.
Air pumpand A long barometer-gauge was added to the air-pump, having
Busse a scale movable by an endless screw for adjusting the zero to
the surface of the mercury in the basin below it. In noting the
_ experiments, the height of the mercury in the gauge was sub-
tracted from that of a barometer suspended in the same room.
Thermometer, Having by accident broken the small thermometer attached to
the bellows-frame, we registered the temperature from another
Receiver. thermometer placed outside of the receiver. The capacity of
the glass receiver is 275 cubic inches, and that of the effective
part of the pump barrel 26:7. Nothing but pomatum was
used between the brass plates and the receiver, on account of
wetted or oiled leathers being known to afford a great deal of
Vapour. vapour. Notwithstanding this, the gauge was depressed by
vapour ; for, on exhausting the receiver, the gauge indicated
Exhaustion, two tenths of an inch less than the barometer, but when again
exhausted, after placing a cup with sulphuric acid'in the re-
Sulph. acid ceiver, the difference of the two was only 0'06, and in one case:
used to absorb WE Could perceive no difference. For this reason, in all the expe-
vapour, riments, except those on water, alcohol, ether, and oil of tur-
pentine, a glass containing five or six ounces of sulphuric acid
was placed by the bellows in the receiver. With this pump,
and using the acid instead of muriate of lime, water has been
Ice produced frozen by Mr. Leslie’s process in two minutes, while the ther-
in 2", mometer in the room was at 67°.
Plate V fig. 1 (opposite page 240 of the present volume)
represents the apparatus made use of for transferring liquids
into the exhausted receiver. It consists of a small glass. tube,
graduated, which screws on the cock above the transfer-plate :
the top of this tube is closed by a piece of ground glass smeared
with pomatum. To the other end of the cock, under the
plate, a small semisph¢rical brass dish is screwed, to catch any
liquid.
Plate.
ON THE SONIFEROUS VIBRATIONS OF THE GASSES. 163
liqnid that falls through the cock, and prevent its injuring the
bellows.
Every time, before the receiver was exhausted, the wooden
pipe was carefully tuned to 0'2250 of a monochord or sonometer,
divided decimally, the monochord being tuned accurately to a )yfonochord.
C fork. The box of this monochord is made of straight-grain-
ed deal, and is 36 inches long, three inches wide, and 2°5 deep.
Over two immovable bridges, placed 30 inches asunder, a steel Its wire,
wire, 0'017 of an inch in diameter, is strained by two endless
screws, placed at the extremities of the box, which act like the
screws ofa modern English guitar. A long wire is preferable toa
short one, because a small alteration of the tension or tempera-
ture will cause a less perceptible difference in the pitch of the
sound it produces. Lord Stanhope used steel wire on his cu- Should be of
rious monochord, finding that it did not keep continually ee
lengthening, as brass or iron wires do when the tension is con-
siderable. A curious experiment is related of the Stanhope
monochord, which I have never yet seen explained. Two
equal wires were put on it, and brought in unison with G, an
octave below the treble cliff. One of the wires was then
shortened as little as the eighteen-thousandth part of an inch,
and this was said to produce invariably an audible beating, Beats.
which could be very sensibly felt with the finger as well as
heard! ‘What was the cause of this beating? The length of
the G wire was 20 inches, which could be divided by that in-
strument into 360000 equal parts, consequently the length of
the altered wire was 359999 of those parts. Now, the vibra-.
tions of strings, which differ in length only, being in the in-
verse ratio of their lengths ; if we assume 180 as the number
of vibrations in 1” of that G at concert pitch, the shorter string
will make only 180°0005 vibrations in 1”, and consequently
not a single beat can be produced by such an imperfect unison
in half an hour* ! The beating that was produced, therefore,
remains unaccounted for.
* Sauveur, Chladni, and Dr. T. Young, consider every Ut or C as a Concert pitch.
power of 2, taking the fundamental C forunity, At this pitch, middle
C makes 256 ‘acoustic vibrations” in 1”: Sauveur’s experiments, in
1700, give 244, Euler and Marpurg attribute to thesame C 236 and
250 in 1”; Cavallo gives 256°8; Smith 247; Sarti 262; Robison 240;
Hawkins 238°6 ; and Farey 241°5.
j Mz a Doctor
164 ON THE SONIFEROUS VIBRATIONS OF THE GASSES.
aeare of the Doctor Crotch remarks*, that a monochord-wire should be
stretched equally at both ends, or else it will be inaccurate,
Chladni and © The only experiments on the sounds of the gasses, with which
Jacquin’sexpe- T am acquainted, and which have preceded ours, are those
re a made by professors Chladni and Jacquin at Vienna several years
Their appara- ago. Many objections might be made to their apparatus.
nar It consisted of an open organ-pipe of pewter, fixed within
the neck of a glass receiver, furnished with a stop-cock
above the pipe, and a bladder on the outside. When the
apparatus was sufficiently filled with gas, the blast was excited
by pressing the bladder : this was done over water. The tem-
perature during their experiments was from 54° to 59° of Fah-
Length of the renheit. The length of the vibrating column of air in their
PRG 4 pipe was about 15 centimetres, or 5°Q inches; hence it would
pitch 11331 produce a sound of three octaves higher than Ut 3, or the tee
59. nor-cliffC, Their results will be mentioned farther on.
Priestley and The experiments of Priestley and Perolle, with a bell rung by
Perolle’s exp. wheel-work, had for object only to determine the zntenszty with
which sound is transmitted by different kinds of gas, and are
therefore dissimilar from those which I shall now describe.
Exp. 1. 1, The receiver being exhausted till the gauge stood only
Nitrous oxide, O'44 of an inch lower than the barometer, nitrous oxide, pro-
duced by decomposing nitrate of ammonia, was transferred from
the gas-jar into the receiver of the pump in four successive
quantities. After each transfer, the scale of the gauge was
‘adjusted, and the movable bridge of the monochord slid till
the wire and pipe were in unison. While this was doing, the
gauge ascended a small quantity, as we had anticipated, from
the absorption of vapour, by the sulphuric acid. To save
Explanation of room, as the mode of operating was uniform, I shall dispose
the tables. 5
each gas in a separate table of five columns, the first, from the
left, showing the number of successive quantities, and the
name of the gas; the second, the temperature ; the third, the
guantity of rise ; the fourth, the pressure after that rise was ob-
served; and the fifth, the monochord lengths corresponding
with the pitch of the organ-pipe. No settled portion of time
was allowed for the gauge to ascend. The sound of this was louder
and deeper than that of any other gas, and in quality of tone
* Elements of Therough Bass, &c, 4to, 1812. =
(timbre)
ON THE SONIFEROUS VIBRATIONS OF THE GASSES. 165
(timbre) resembled the sound produced by a bad-toned bag-
pipe. The pitch was alittle more than a major third below
thatff atmospheric air: our preceding experiments with an
open pipe and less accurate apparatus gave 3d.—comma.
1. Nitrous oxide - -{671]:‘07[ 817 | ‘27350
Bis ey we ve =i] 6%) 612 | 1575201,*28000
3. = = © s = =} 67 | °20 |} 23:02.) °28550
ee eee a ee | | OF | 95 | 2077 “28675
We thought the acid in the receiver was become a little
more opaque, but no froth appeared on its surface, as it had in
some of the experiments. On opening the stop-cock in the
transfer-plate, and working the pump, the sound of the pipe
became more acute, like the sound of a violin-string, which is
slowly shortened by sliding the finger. ,
2. Carbonic acid, disengaged from chalk by dilate sulphuric Expt.22
acid, and collected over water. The tone of this gas was weak Carpe Aes
and reedy*.
1. Carbonic acid - 61°5 | °30 | 10°23 ! :2740
Bera ata Soe le eS) ogg! papag bgene
3. = = = = = = | — 1 +34 | 25-96 | -2850
Atmos.air - = = —— | — | 28°80 | ‘2850
3. This gas remaining in the receiver, the pump was worked 2#P- 3
i : : Carbonic acid
till the pressure on the gauge was 14°34, when a quantity oO and hidrogen,
hidrogen gas wasadded. ‘The sound became more acute with
aslide, and clearer and smoother than the sound of carbonic
acid alone.
Carbonic acid - - -]| O1°5 14°34 | ‘2760
Hidrogen added = - - 28°80 | *2115
Do. remained - = - 65 '| 28°15 |" 2125
The pitch of these gasses was not altered by working the pump
till the pressure was 14°46 ; but on filling up the receiver with
atmospheric air, the sound was depressed to*2215, and the
gauge rose 0'30 ina very short time.
f * Chladni found the pitch of this gas to be almost a major 3d below
that of atmospheric air, a result which accords with this experiment.
4, Chlo«
166
Exp. 4.
Oximuriatie
gas.
Exp, 5.
Olefiant gas.
Its pitch,
Exp. 6.
-Olefiant and
oOximuriatic,
Pitch,
xp. 7.
\xigen gas,
ON THE SONIFEROUS VIBRATIONS OF THE GASSES.
4. Chlorine gas, obtained from oxide of manganese and mu-
riatic acid, and collected over water. In this experiment the
gauge was not used. The receiver was filled by three succes-
sive and nearly equal quantities of the gas. The pitch was not
guite a minor 3d lower than that of air.
1. Chlorine gas - -=]67|{——{—— | ‘25400
BL ee meee Eee ee Se egies
Be nee my eee ee ad led i 279CO
5. Olefiant gas, or supercarburetted hidrogen, produced by
boiling, in a glass retort, alcohol and sulphuric acid.
1, Olefiant gas - - -]|60]:a9[. 7°39 | ‘23400
Diy ee ene wee) = BL 1s | 1B On eee
SB. ) ee el oe = PSO 16 22°02 1 r24an0o
Bee Be aga Ae erin ieeamnaae
6. The pitch, taking the mean length, is almost a major semi-
tone below that of atmospheric air. Having noted this experi-
ment, the pump was worked tillthe pressure was only 15°68,
and three measures of chlorine gas were added, in succession, ta
the olefiant gas, which remained in the receiver.
1. Chlorine added + - | 55 [| 2°70 | 19°48 | :25650
25 - = = = = =| 54] ~-- | 2014 | ‘26000
fos - = =| 54] 4°39 | 21°76 | ‘25550
2) wait et “bey digas! 2 = do zeae domed ag
; - = = = =| 53 | 641 | 21°34 | ‘26925
During this experiment, the barometer ascended from 29°18
to 29°75. The tone was very peculiar, and cannot be easily de-
scribed. After each addition of gas, the pressure began to di-
minish, andthe pitch to ascend. The mean length gives the _
pitch nearly a superfluous second lower than that of atmosphe-
ric air. The brass plate of the pump was found entirely co-
vered with a purplish gray oil, which was extremely difficult to
remove, and which was not quite removed for a long time
after. ,
7. Oxigen gas, obtained from oxide of manganese by heating
it in an iron retort.
1. Oxigen gas - - -| 69] .03| 7°95 | '23375
2- = = = = = «| 69] °10 | 15°81 | 23600
3. = + - + - -|69|-~-| 23-61 | 23900
Here
ON THE SONIFEROUS VIBRATIONS OF THE GASSES. : 167
Here the lever of the bellows breaking, we had to begin this
experiment anew. ‘The gas was pumped into a bladder and
used again.
‘25 | 15°61 | °23600
‘40 | 22°61 | -23800
29'98 | 23875
. Oxigen gas - - e 69°5 | ve 8'26 | 23250
1
2.
Ses, ot eee
4 |
A mean of seven gives the pitch a little more than a minor Its pitch,
semitone graver than that of air—Chladni found it to be a semi-
tone or nearly atone; and our former experiments, with the
little open pipe, make it not quite halfa comma.
8. Nitrogen gas, obtained from small’ pieces of lean muscular Exp. 8.
flesh (beef) and weak nitric acid, gently heated in a glass re- Nitregen gas.
tort. The gas stood over water for twelve hours before it was
used, |
1. Nitrogengas - --]68 f|:es| 7°72 2185
Doo = Km mp = | 68, 4°14 | 15:20:]"2250
Smee = = = = =| 6875 | 05) 22°95 | 2275
4 ~ - - - = = ~} 63 |- =| 30°00 | -2290
This gas produced a very weak, dead sound ; the same in Its pitch.
pitch ascommon air. Chladni found it almost a semitone
graver.
g. After working the pump till the pressure was only 22°5, Exp. 9.
oxigen gas was added to the nitrogen in the receiver, till the pi and
pressure was again 30'0, when the sound of the mixed gasses
was 0'2335, or almost three commas below the sound of common
air. Chladni found that a mixture of these two gasses gave a
sound in unison with that of atmospheric air, being more acute
than either gas alone. ‘* But before the mixture of these fluids
had become homogeneal by repeated pressions of the bladder,
the sound was not appreciable, because the vibrations could not
be isochronous.” (Chladni, § 67.)
10. Axotic gas, procured by setting fire to a piece of phos- Exp. 10.
phorus in atmospheric air confined over water. It was inflamed ee
with aburning lens. Before the gas was used it was left in
sunshine, over water, for several hours.
168 ON THE SONIFEROUS VIBRATIONS OF THE GASSRS.
. Azotic gas - =
1
Wedel se mint oh wu ‘10 | 14°50 | ‘2210
Soe ee et a A Doo ones
Yan a Dr he genes ds eh irae 09
———
a
ite | ‘10 | 7°30 | °2210
(A little air Added common air = - | — | + ~ | 29°40 { °2225
added.)
Pitch, A mean of the four gives the sound a little more than a
comma more acute than the sound of common air.
Exp. 11. 11. Sulphuretted hidrogen, obtained from powdered sulphu-
Su! phuretted
Birceen. ret of iron, a little water, and weak muriatic acid, gently heated
in a glass retort, and collected over water. A large quantity
of the gas was absorbed by the water in the pneumatic trough.
1. Sulphuretted hidrogen | 62°5 | ‘39 | 6°88 | ‘0000
2- = = = = = =| 615 | 68 | 13°74 | 2035
By ae ey pe eo eG. SO ke ane
4.0 ee ew ee ow SSO.) VO 27 ieee, es
The least so- This is the least sonorous of all the gasses that we have tried.
paises, of the The sound was hardly appreciable after the second tranfer of
gas ; and even after the third it was impossible to maintain a
continual sound by the most rapid action of the bellows. The
Its pitch, pitch of this gas, from a mean of the three lengths, is not quite
a minor tone higher than that of common air, but is more than
amajor semitone. At the end of this experiment, the sulphu-
ric acid placed in the receiver had a froth on its surface about a
quarter of an inch high, and of various metallic colours. And
we observed, that a part of the oily matter produced in the
sixth experiment, and which so obstinately adhered to the plate,
could be much more easily wiped off.
Exp. 12. 12. Hidrogen gas, obtained from water, bits of zinc, and
ieee sulpharic acid.
1. Hydrogen gas - =] 61'5[°10] 7°96] °111
2. - 7 = = = = =| —] 08 | 15°36 | 111
4s sles!) ba PA O72 ag
Be Bee Gch ead oe - - | 28°86 | 111
Its pitch. The sound was weak, and more than an octave and comma
above that of air. On working the pump till the pressure of
Breath added, the gas was 14°28, and adding breath till the pressure was again
28°86, the sound of the mixture agreed with'1§15 of the mo-
nochord ; and the gauge soon rose again O'2.
14, Light
ON THE SONIFEROUS VIBRATIONS OF THE GASSES, 169
13. Light carburetted hidrogen, oan by distillation from Exp. 13.
Light carbu.
chips of deal. oi, ee deat
1. Lt. carb. hidrogen- - | 59|]- -|- = - | 1075 alas
eee ee eh oe 1 Lae | 075°
Be = = = = = «= al—] 19 | 21°55 | 1075
4. = = = = = = -]60]- - | 2845 | +1100
5eo- = - = = = =] —]- - | 29°13 | 1120
The pump being worked till the pressure of the gas ‘was
again 14°92, the sound was ‘1060. The pitch, from a mean
of the six monochord-lengths of wire, is more than an octave Its pitch,
and two commas above that of air, |
14. Ether. The graduated glass tube was screwed upon the cca
stop-cock of the transfer plate, and filled with ether. The Satie
_ Pressure on the gauge being 0°62, with no acid in the receiver,
a small part of a cubic inch of ether, as shown in the left-hand
column of the following table, was admitted into the receiver
through the stop-cock,
"05 | 1. Ether - - - ~- -[60]| 0 | 1°48 | ‘09650
705) 2. 2 = = = = =f —
7 | cata lle at ER ee fs
705} 4. - - = - = - -]—]- - ea Re
‘05 =i hig Aas ily ahd
li |
6°10 | °11450
‘00 ce ST gM AN te a AR Iss wd oN ge BC.
After the seventh transfer of ether, we applied a cloth The receiver
dipped in warm water round the receiver. The gauge fell oor
0°38 ; and we imagined we could hear two sounds, about a fifth
safe: in pitch ; the one a wheezing tone, the other much
clearer. The hemispherical dish was about half full of liquid
ether within the receiver. By a mean of six lengths, the pitch
is almost an octave and major semitone more acute than the
sound of atmospheric air. The air and ether vapour give a
sound which is only about a ae minor semitone
more acute.
15. Alcohol, introduced into the receiver in the same manner Exp. 15.
as the ether, sunk the gauge only 0°55, and produced no sound. ge
When air was added to fill the receiver, the sound was 0°2260,
and very indistinct, ‘Thermometer in the room 60°, barometer
29°7. Hot
170
Other expts,
Theorems,
ON THE SONIFEROUS VIBRATIONS OF THE. GASSES,
Hot water, liquid ammonia, and oil of turpentine, were suc-
cessively treated like the ether, and found to produce no sound,
and but very little depression of the mercury in the gauge.
Air and hidrogen gas are the only elastic fluids that haye not
varied in pitch with a considerable variation of pressure.
At present, I shail not enlarge .on these experiments ; but
subjoin a table, showing the redaéive lengths and vibrations cor<
responding with the sounds of the gasses when the sound of air
is taken as unity. ‘‘ Des faits, et point de verbiage, voila la
grande régle en physique comme en histoire.” (Dalembert.)
Jn the right-hand column of ithe table I have placed the loga-
rithms of the intervals with air ; for the value of any interval
is the logarithin ef its constituent ratio*.
* See Dr. Smith’s Harmonies, sect. 1; and a Table of Intervals, by
Mr. Farey, in the Edinb. Encyclopzdia, vol. II, 1810.
Postcript, The pitch or value of a sound depends on the frequency
of its vibrations. It has been asked—“ Why should not the measure
of an interval be the difference of the values of its terminating sounds ?
and consequently why sheuld not intervals be compared by the diffe-
rences of the values of their sounds?” In answer it has been said,
that ‘‘ the measure of an interval estimated in that manner wonld vary
according to the unity of time chosen for representing the value of the
sounds. For, let aand b be the numbers of vibrations of two sonorous
bodies in one second; ma and mb will be the numbers of vibrations of
these bodies ina time m times greater. The interval would then be
measured in he first case by 6— a, and in the second case by mb — ma,
a quantity necessarily different.” The following theorems respecting
intervals, translated from A. Suremain Missery (1795) may be usefal
to some of your readers, who are not familiar with the sabject.
“* Considering intervals ia one direction only :—
“T. The prodact of the constituent ratios of two or more different
intervals is the constituent ratio of the interval which would be equal
to their sum.
“1. The quotient of the constituent ratios of the two intervals is the
ratio constituting the interval which would be their difference.
“111. Every natural power of the constituent ratio of an interval is
the ratio constituting the interval which would bea multiple of the first
imarked by the degree of the power.
“ TV. Every naturab root of the constituent ratio ofan interval is the
constituent ratio of an interval that would be an aliquot part of the
first marked by the degree of the root.
“V. Any fractional power whatever of the ratio constituting an inter-
val is the eonstituent ratio of the interval which would be a portion of
the first marked by the exponent of the fractional power.” 75. For
authors on this subject, see Forkel’s Allgemeine Litieratur der’ Musile,
kap. 1. of the second part ; Leipsic, 1792.
ON THE NECTARIES OF FLOWERS. 171
a Mean Lova-
&| Aeriform fluids. |lengths of roman oe cena’ rithms of
qa wire. engis, vibrations. intervals.
Se ee (eae nee.
1|N\trous oxide gas -|2814375 |1:250833 |o'7y9467 |'097 1995
2\Carhonic acid - -|2787333 11238814 |9'807223 |*0930003
4\Chlorine - - -}2699167 |1:199610 |0'8335g0 | 0790473
6\Do. and olefiant - -|'2630500 |1:169111 |0°855351 | 0678558
5jOlefiant - - -|2386125 |1:058233 |0'944882 |'0246225
7\Oxigen - - - -|2362857 |1:0501 50 10'952237 [0212549
Q)Do. and nitrogen = -/'233500011'037778 |0'963507 10161044
3\Carb, 2. & hidrogen |'2333238 '1:037037 |0'964286 | 0157942
—'Common air - - -|:2250000 | 1:@00060 |1:0OG0CO0 }'0000000
8|Nitrogen = - -|.2250000 |i 000000 | 1'000000 | OOOOD0O
IQ;Azotic - - = -|'221625010'085000 | 1'015228 | 0065637
14\ Ether vap. and air -}'218750010°972222 |1°'028571 | 0122344
11/Sulph. hidrogen —_-}' 2060000 |0'915556 | 1092233 10383153
12|Hidrogen - = = -|'1110000|09'493333 |2'027027 |'3068595
13|Carburetted Do. - -|'1084167 |9'481852 |2°075326 |'3170803
14| Ether vapour - -|'1063283 |0'472570 |2°1160S8 |'3255337
14:Do, highest - - — -|096500010'428889 |2°33 1606 |'3676552
Sa ng NE RAR ha CT AD IE IS
I remain,
Sir,
Your humble Servant,
ARNOLD MERRICK.
Quern’s Road, Cirencester,
92d Sept. 1812.
Il.
On the secret and open Nectaries of various Flowers, In a Let-
ter from Mrs. Acnes [BBETSON.
To Mr. Nicholson.
SIR,
N the exact dissection I have given of a flower in your On thenectary
Journal for July last, the explanations of the calyx, corolla, of flowers.
aud stamen, were alternately given, their peculiar vessels de-
scribed, and the separate cylinders, which convey those vessels
to thestalk, accurately and exactly marked. There remains,
therefore, of the flower but two parts to develope, the nectary and
the pistil : the most important, indeed ; and which have never,
I think, been rightly explained, or properly delineated, particu-
larly
172 ON THE NECTARIES OF FLOWERS.
Jarly the former. I shall therefore dedicate the greater part of
this letter to this subject: first, to the display of the various
functions cf the nectary ; secondly, the importance of this part:
of the ‘lower to botany in general ; thirdly, the description of
the many different sorts of nectaries both concealed and open ;
and fourthly, the curious mechanism displayed in their various
formation.
Honey sup- Tt has been conceived, and frequently i by our first
eee OF i physiologists, that the only purpose, or known use, of the honey
vite insects,so found in plants, was to tempt the insect tribe to visit the
meee cakes flowers, that, while inserting their heads into the interior, they
poilen from might, by rubbing against the stamen, take up some of the
rare *° powder of the pollen, and convey it to the pistil in other
flowers ; and thus impregnate seeds, which, without their assist-
ance, might not be able to procure the powder necessary to their
completion, ‘That nature has bestowed on the insect tribe the
curious knowledge necessary to seek the honey in a flower*,
and make their search thus serviceable not only to themselves
but to botany, I have no doubt ; but I am equally convinced,
that few, very few, of the icone plants of any country,
Thisassistance (even of the dicecian class,} require such assistance ; and that if
seldom neces Aowers were never removed from their native soil, they are all
sary. > y
sufficient to perform every part which nature has assigned them,
in fructifying their own seeds. It is very little known, (because
it has never before been a matter of serious investigation,) how
Mobilty of much motion indigenous plants possess. That they are scarcely
angst ever still, is an absolute fruth; and that on a warm day we
need not seck in the plants of other countries that curious and
regular motion to be found in each field in ourown. That the
pistil and stamen regularly bend to each other, so as to enable
* Any person, who has seen an insect seek the honey in an antir-
rhinum, will be convinced, that this knowledge is necessary; and that
without it the insect would fly toany other part of the flower, but the
oneat which it opens : whereas it settles at once on the round top, fixes
one foot on the opposite petal, which it pushes open, inserts the head
and shoulders within the flower, lengthens the proboscis, and draws up
the honey. All this is the work of a few seconds of time,and it is done
in so perfect a manner, so immediate and so direct, that nothing but a
thorough knowledge of the flower could enable the imsect to act thus
decidedly,
ON THE NECTARIES OF FLOWERS, 173
the femiale to acquire pollen sufficient to fructify its seeds, there
can be no doubt with those who thoroughly watch flowers ; also
that the mechanism for the purpose exists in them, and is always
found capable of performing its office in indigenous plants. If,
therefore, the pistil and stamen can almost always suffice, withe
out aid, to impregnate the seeds, is it likely, that so large and
seemingly important a part as the nectary should be placed in
every flower, when not likely to be necessary but to a very few ?
But the nectary has, in reality, a much more important task to Nectary not
perform; and its history is beautiful and perfect in all its parts. vie gto
There is in every flower a concealed as-well as an open nectary ; dene
_ its luscious juice is formed within the vessel of the line of life,
and increases in sweetness as the plant advances towards
flowering. It isthis-juice which appears at the head of the
stigma in one ot many glittering drops, which dissolve the pol-
len, conveying the joint mixture to the seeds, which it impreg-
nates. Without.this liquid, therefore, the seeds would not be
completed. Hence the cause of nature’s forming two nectaries
in each flower, which are the sacred deposits of this juice; the
one that insects can attain, the other closed to them, and so am
well guarded when not wholly closed, that death generally fol-
lows the attempt to seize it: for though the insect tribe are
taught to find the open one, yet if they could take ali the honey Why two neea
thus deposited, the seeds could not be impregnated. Thus ties are ne-
Nature, ever indulgent, bestows as long as the zeneral good will aio
allow ; but gluttony brings its own punishment.
Nor are the purposes already mentioned the only ones for Farther use of
which the nectary was designed by nature, and bestowed on ‘He nectaries,
flowers. The various alteration of the juices ; the first feeding
of the embryo of the seeds and buds; the innumerable combi-
' nations formed in the interior of plants, of which the nectarious
: juice is the basis ; and the decomposition of water, which the
solar microscope so admirably shows to be constantly going on
_ in plants ; must owe much to the juices of thenectary. I have
observed for some time past, that the line of life (the source of
the nectary) bleeds whenever it-arrives at that part of the stem Bleeding of the
where the leaves shoot, and the buds come forth ; and have so
gontinually seen it ooze out when greatly magnified : but I was
most curious to know whether this bleeding was the cause of
that change of colour, which so frequently takes place in many
- different
174 ON THE NECTARIES OF FLOWERS.
different plants at that time, when even the stalk, as well as the
axilla of the leaves, is reddened by its tint. I took out, there-
fore, the whole cylinder belonging to the line of life, and pro-
cured a drop or two of this luscious liquid. I then divided the
wood from the same plant, and by pressure obtained a little
sap : and the mixture of the two immediately changed the co-
lour of the liquids, and converted the light green of the sap to
adark red colour. That the sap running in the perfect wood is
Effect of the almost always a pretty powerful aikali, I have long been con-
oir deta vinced (differing from that found in the alburnum -:) and that
plants. 8 the buds, on the contrary, are more or less acid, may be easily
shown by cutting and then immersing them in a weak alkaline
liquor. The direct change of colour produced in the wood by
passing a feeble electric stroke through a plant also proves it,
since it reddens the wood vessels, but has no such effect on the
buds. We may therefore, I think, conclude, that the redden-
ing of the stalk is caused by the bleeding of the line of life, and
the mixture of the acid and alkali in the bosom of the leaf:
and we may also look to the nectary for three of the most
powerful effects observable in the life of a plant.
I now turn to-the third division of my subject, and shall
show the various species of nectary found in plants, both con-
cealed and open. I need not here represent the manner in
which I dissect flowers, as my former letter has shown it, and
proved, I hope, how impossible it is, that after cutting them in
three different directions, I should be mistaken in the formation
of their various parts; since in such a display they would mu-
tually be the means of detecting each other, if not critically
exact in their delineations. All flowers, with respect to the
situation of their seed vessels, may be divided into three distinct
kinds: those which have their seed-vessels above the flower ;
those in which the same part is found much below, and those
in which the germe occupies nearly the centre. In the first and
second the secret nectary is generally found in a deep cavity
either above or below the seed-vessel, according to its situation
in the flower ; but in the last it is so various, that there is no
The situation giving rules to find it. In a monopetalous corolla the secret
of the secret nectary generally forms alittle box under the seed-vessel, which
nectary in mo- q acs ; : :
nopetalous has sometimes the stamen opening into it, and is therefore dis-
plants, covered by drawing out the filaments, and finding their ends
2 steeped
ON THE NECTARIES OF FLOWEKS. 175
steeped in this luscious juice, when there is not any perceptible
m the cup of the flower, Another sort of secret nectary is
found in most triandrian and hexandrian plants; which have triandrian and
their seed-vessels very low in the stem, and the concealed nec- er ans
tary reaching from the bottom of the corolla to the germe. In Sethe
some flowers it is above two inches deep; nor is it useless in
this situation ; it is not only ready to rise to the stigma to im-
pregnate the plant, but it has various vessels passing through the
exterior of the seed-vessel (where it joins the nectary) to nou-
rish the embryo till the flower decays, and the rest of the lusci-
Ous juice evaporates. In the tetradynamian flowers, as well andin tetrady-
as the geraniums and some others, the apparent well is on one ®4™ian plants.
side of the stem, reaching from the corolla to a certain mark,
or to a stipula; and always distinguished by one of the leaves of
the calyx turning up, while all the rest turn down. The open
nectaries of these flowers are as various as the plants. In most
of the geraniumss it is a ¢rowgh between the corolla and stamen,
rising round the pistil, and oozing up from the well below.
In the triandrian plants the second nectaries are generally either
cavities at the bottom of the stamen, or vessels managed within
the corolla. The admirable double nectary of the iris deve- The double
lopes much of the intentions of Nature in its formation, since ®&¢tary of the
its secret repository is not quite closed, but is sure to catch the ip
insect that attempts to seize its contents. The open nectary is
in some species a beautiful fringe with a wide vessel down the
reflected petal, and in others it consists of three honey-bearing
excrescences flowing from the same source: but the secreted
juice is found in a deep cavity in the stem, having a trough at
the top, and within the fiower, to hold the precious liquid.
The two points of this trough secure the insect as it crawls
down between the petals, when, not contented with the feast
_, the open one bestows, it stretches out its proboscis to get at the
honey within the trough. How often have I stood contem-
plating this picture, and seen the insect try to insinuate itself
Jower and lower, though apparently well informed of the danger
it was encountering! I found the other day, in a yellow iris The nectary
on the border of theriver, abee, which, having ventured too seizing an ine
far, was caught by the projecting points of the trough, which, ea
like the stamen of the berberris and apocynum androsezmifolium,
had got it fastened between them : and it wouldthere have died,
. had
176
Nectaries in
the diadel-
phian class,
Didynamian
plants, and
those with
naked seeds,
ON THE NECTARIES OF FLOWERS,
had I not released it; for the warmth or moisture of its body so
contracted the spjral wire in the petals, as to press them tight
against the insect. Nor could it ever have regained its liberty,
Ji was really astonishing to see the flower able to resist the
struggles of so large a creature, but the very violence of its
exertions seemed to increase its danger, by pressing from below
such a quantity of liquid, that it was almost drowning in honey.
The best way of getting at the secret nectary of the iris is not
by the flower, but by cutting thestem where it is marked for
the beginning of the seed-vessel, as that points out also the ter-
mination of the nectary.
The two nectaries in all the diadelphian class are » most admi+
rably managed. To look at the exterior of the flower it would
appear almost impossible to find room sufficient for one, and yet
all those flowers possess a very perfect double nectarium, with
all the various vessels its different offices require : a deep trough
within the cylinder of the males is filled even to half the height
of the filaments with this precious juice ; and that the bees also
may have their share, there is a nectarious ball on each side, on
which the banner is fastened, thus serving a double purpose.
As the insects draw the honey forth, it is eonstantly replenished
from the trough below ; and the exquisite beauty of the con-
trivance is completed by its not only being ready for supplying
the stigma, should the weather be unfavourable to the ripening
of the pollen (asin this case it loses much of the nectarious
juices by evaporation) ; but it is also all that time feeding the
embryo in the seeds ; which have innumerable vessels running
through the pod, and most plainly to be perceived in the solar
microscope, to imbibe this juice fer the nourishment of the
young plant; but no sooner does the cylinder of the stamen
decay and fall off, and the pods increase, than the skin thickens,
the vessels disappear, and the embryo no longer receives nous
rishment except from the stalk, and its own nourishing vessels,
In the didynamian plants, and in all those fiowers which have
uncovered seeds, the nectarious juice is secreted in a box in
the large part which lies directly under the seeds ; while the
open nectary is either found at each corner, or opposite to the
seeds, In giving the exact picture of the flower of the peach,
in the Journal of July last, dissected in three different ways, I
left a square at the bottom of vay seed-vessel not allotted to any
2 use ;
ON THE NECTARIES OF FLOWERS. 177
use ; it is this which forms the nectarious box, while the inte-
rior lining, or inward cylinder of the stamen, forms the open
nectary of all the icosandrian class. Wherever this yellow A yellow mat-
matter is found, (which appears something like softened bees’ ae:
wax) it always indicates the nectary, as does also a very brilliant tary.
white substance found at the top of the seed-vessel in ail pen-
tandria digynia plants, which is also a never-failing sign of its
presence. If the dissector finds it difficult to discover the se-
creted juice, there is a little insect, which may be seen with a Insect livingin
small magnifier, that always leads to it. It is of various shades See? SF
of brown, raises its tail, and the half of its body above, smooth-
ing down its very short wings. It lives wholly on the nectary
of plants, and is found there alone. When a drawing, or a sort
of map is taken at the bottom of each flower, showing the
manner in which the vessels branch off to form their appropriate
ingredient, it is exactly seen, that not the breadth of a hair is
left unemployed and unallotted, and that the most marked ad- peautiful ad-
justment takes place in this respect : and this is done without in justmentefthke
the least disfiguring the parts ; ail appear as perfectly to coincide" ”
as if this alone was the object in view, and yet for what great
ends, what noble designs! Ioftenthrow down my pen and
pencil in despair, ashamed of the folly of attempting to give an
idea of works almost too great for man even toconceive. It is
certainly true, that we are more struck with the power of the
Almighty, when we contemplate his small works, than in the
view of his larger chefs d’ceuvre: when each diminutive object
is so highly finished, it would appear the peculiar care of provi-
dence ; and yet on farther examination of these minor objects,
we find all equally perfect and beautiful.
. To give the double nectary inal] plants would be an endless
business, equally tiresome to the reader and writer ; but I think
I shall have given (with the following examples) sufficient to
prove the trath of all I have advanced—*‘ That there is a con-
cealed as well an open nectary in all flowers ;” and that the si-
tuation of both is generally regulated by that of the seed-vessel,
which appears to connect it indifferently with calyx or corolla, Nectary cons
stamen cr pistil : but, however this may seem a matter of no nected with
moment, I doubt not it is of the wtmost consequence to the the cays,
parts, and regulated with the greatest judgment ; and that, when
I am still better acquainted with the subject, I shall discover the
Vor. XXXIII, No. 153.—NovemsBer, 1812, N _ neces-
178 : ON THE NECTARIES OF FLOWERS,
necessity of this variation in the situation of the nectaries: for
there is not any thing more striking in dissecting plants, than
the simplicity and ease with which the cause is discovered in
the effect. As a specimen of the nectary in the calyx, I shall
give the stock (pl. iv, fig. 1.) Here the two opposite leaves
serve as the hidden nectary, and the excrescence alternating the
stamen forms the open one. For an example of the nectary
in the corolla, I shall give the fritillaria : in thisa sort of basin,
fig, 2, corresponds with the secret nectary under the seed-
vessel. Inthe stamenit is either at the bottom of the fila-
ment, fig.3, AA, or joined in a more conspicuous manner, as
Nectary in the in the corn flower, fig. 4, BB, which is distinguished by many
corn flowers curious circumstances peculiar to itself, which I shall enlarge
upon another time, when I give the dissection of the sta-
men. In all pentandria digynia plants, we have examples of
the nectary joined to the pistil and seed-vessel, as at fig. 5 :
CC being the open, and DD the closed nectary. Here we also
* see a proof of that brilliant white matter, which always an-
nounces the luscious juice. I shall present also one example of
a plant having its seed-vessel above, in the passion-flower, fig. 6.
Here the nectary is sure to be placed in the following manner ¢
the open one at EE, the closed one at F, perfectly secreted from
all danger, yet corresponding with the other nectary, and free
to communicate its juices for the benefit of the seeds, and re-
pairing any excess of evaporation lost on the stigma. The
secret nectary in the iris I have already shown to be a species of
well, see fig. 7, from H to H, while the corners of the trough
in the fiower are seen atII. The secret nectary in the gera-
nium is shown, fig. 8, from K to K; and the open one, a
trough round the pistil at LL. The two nectaries in the silene,
cucubalis, lychnis, &c., are displayed at fig. 9 : MM being the
secret one, NN the open nectary. Those in al] flowers, which
have uncovered seeds, are seen at fig. 10; PP the open one,
OO the secreted box. I have avoided giving those most com-
monly known, as I preferred the nectaries which have not yet
- been noticed by botanists, to show more certainly, that two are
found indifferently in all plants.
‘Coaclusion of I shall now conclude my letter with a few words on the me-
the subject. chanical properties of the nectary. There is, I believe, no nec~
tary, that has not the power of giving out its juices, or retaining
them,
~~
‘O
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS. 1
them. In the delphinium, fig. 11,1 have seen it when almost
full and turning down, still retain its liquid ; nor could I at first
conceive how this was managed, till, on dissecting it, I found
that there was an inner lining, which contracted at RB, when the
round part was much distended ; and thus prevented the expen-
diture of its juices. At fig.5, the nectary has not only the
power to retain its juices, but to throw or eject them on
the stigma ; which I have repeatedly seen it do on a warm
sunny day. Ihave before observed how uncommonly per-
fect the mechanism is in most flowers in very hot weather,
when the spiral wire seems full of vigour, and all its various
offices are shown with double force. It is on such a day the
liquid of the pistil melts the pollen with more ease ; for in ge-
neral the drop appears on the stigma but one hour, and then re-
tires. This alsois the mechanism of the pistil; the curious
motion in the nectary of the ranunculus is known to a few;
the leaf, which is formed to cover‘it, always encloses it tight if
the wind blows, but, on the contrary, admits the rays of the
sun to it, if itisa jine warm day. ‘There cannot be a more ex-
cellent barometer, for it will denote each cloud and each change
of the atmosphere ; and there are many flowers which draw on,
and put off their cover, whenever a threatening cloud appears. Mechanical
In watching flowers very exactly, it is really a perpetual source of ete of the
astonishment—the varying mechanism is so great, that no per- :
son who would take the trouble of sitting by a plant for a few
hours, could ever after admit a doubt of its being governed by
the mechanical powers,
Your humble Servant,
AGNES IBBETSON.
Ts
Chemical Researches on the Blood, and some other animal
_ Fluids. By W.T. Branpe, Esq. F. R.S. Communicated
to the Society for the Improvement of animal Chemistry, and
_ by them to the Royal Society. :
(Concluded from p. 32.)
Researches on the colouring matter of the blood.
Do; O procure this substance for experiments, I generally Method of col.
employed venous 26 which had been stirred during l¢cting the co.
2 its
>
ed ae OREO Mee Wiad ae
.
180 CHEMICAL RESEARCIIE8S ON THE ANIMAL FLUIDS,
Jouring matter its coagulation ; the fibrina is thus removed, and the colouring
blecd. matter diffused through the serum, from which it gradually
subsides, being difficultly solvble in that fluid ; on decanting
off the supernatant serum, the col uripg matter remains in a
very confi ated form \ Vhe: nodes of procuring it
t ' y mentioned ; but as I
retained interfere much
the colouring principle,
adopted. us !
pected microsco-
¢
le appears to 4
consist of glo-
buies,
vepeneeitiog of
¢ publication, he
ly disproved.
“5 dissolve
ng olourless,
principle
them is.
The aqueous
solution de-
filter, the
re to heat not
alcohol, and
ether,
The precipi-
tate partly so- water,
3 but when digested
luble in acids, in
portion was taken up
his soluble portion as a
produced by. the opera-
*
‘ Effects
Ate 28h OO IR SAU ET TERE
See” SENG CON CA ee
ry,
Sth es « CECCALSE dis asad Urivecree vere
a i
| oT
iil
Engraved by H. Cooper
Drawn buy J Farey
es
{eek
al
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS, 18]
5. Effects of Acids on the colouring Matter. '
A. Muriatic acid, poured upon the colouring matter of the The colouring
blood, renders one portion of it nearly insoluble, and of a matter treated
bright brown colour : another portion is taken up by the acid, hs Negers:
forming a dark crimson solution when viewed by reflected
light ; but when examined by transmitted light, it has a green-
ish hue.
This solution remains transparent, and its colour is unim-
paired by long exposure to light, either in contact with the
air, or when kept in close vessels, At its boiling temperature
the colour is also permanent,
Infusion of galls produces no change in this muriatic solu-
tion, nor is its colour affected by carbonated alkalis, even when
added in considerable excess.
Tt is rendered brown red by supersaturation with caustic
potash, but not with soda, or ammonia : these, and especially
the latter, rather heighten its colour.
When considerably diluted with water its original colour is
much impaired, and the green hue, which it always exhibits
by transmitted light, becomes more evident. .
In preparing this solution, I frequently employed the coagu-
lum of blood sut into pieces, and digested in equal parts of
muriatic acid and water, ata temperature between 150° and
200°. Inthree or four hours the acid was poured off, and
filtrated. The clear solution was in all respects similar to that
above described, although before filtration it appears of a dirty
brown colour. ;
T evaporated a portion of this muriatic solution in a water-
bath, to dryness; it retained its colour to the last, and left a
’ transparent pellicle upon the evaporating basin, of a dirty red
colour : this, when redissolved in muriatic acid, acquired its
former tint, but the colour of its aqueous solution was nearer
brown than red.
B. Sulphuric acid, diluted with eight or ten parts of water, with sulphu-
forms an excellent solvent of the eolouring principle of the ric:
blood.
It may be employed in a more concentrated state, but the
bright colour of the solution is in this case apt to be impaired ;
and when more largely diluted with water, its action is slow
Z and
=
183
with nitric;
with acetic :
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS.
and uncertain. Either the sediment of the colouring matter
from the serum, or the-crassamentum of the blood, may be
indifferently employed in forming these solutions.
When dilute sulphuric acid is added to the colouring mat-
ter, it renders it slightly purple ; and, if no heat be applied,
the acid, when poured off and filtered, is colourless ; so that
dilute sulphuric acid, when cold, does not dissolve this colour-
ing principle.
One part of the crassamentum of blood cut into pieces was
put into a matrass placed in a sand heat, with about three parts
of dilute sulphuric acid. It was kept for twelve hours’ in a
temperature never exceeding 212°, nor below 100°. After
twenty-four hours the acid was filtered off, and it exhibited a
beautiful bright lilac colour, not very intense, and tainted with
green when viewed by transmitted light.
This solution is nearly as permanent as that in the muriatic
acid. Some of it, which has been kept for a month in an open
vessel, often exposed to the direct rays of the sun, is very little
altered. |
When diluted with two or three times its bulk of water,
the lilac tint disappears, and the mixture is only slightly green.
When exposed to heat, the colour gradually changes as the
acid becomes more concentrated by evaporation, and when re-
duced to about half its balk, the lilac hue is destroyed.
The solutions of pure and carbonated alkalis, when added in
excess, convert the colaur of this sulphuric solution to brownish
red ; but in smaller quantities they merely impair it by dilution,
C. Nitric acid, even much diluted, is inimical to the colour-
ing matter of the blood.
A few drops added to the muriatic or sulphuric solutions
gradually convert their colour to a bright brown, and larger
quantities produce the same change immediately.
The action which this acid exerts upon the colouring matter
under other circumstances is nearly similar, and always at-
tended with its decomposition, so that my attempts to procure a
red solution in this menstruum uniformly failed of success.
D. Acetic acid dissolves a considerable quantity of the co-
louring matter of the blood ; the solution is of a deep cherry
red colour. When somewhat diluted, or when observed in
tubes of about a quarter of an inch bore, this solution appears
pers
CHEMICAL RESEARCHES ON THE ANIMAL YFLUIDS. 183
perfectly green by transmitted light. In its other habitudes it
nearly resembles the muriatic solution. . ‘
E, The solution of the colouring matter in oxalic acid is of oe oi
a brighter red than those hitherto noticed; that in citric acid tartarie.
is very similar to the acetic solution, and with tartaric acid the
compound somewhat inclines to scarlet. All these solutions
exhibit the green hue, to which I have so often alluded, in a re-
markable degree.
6. Effects of Alkalis on the colouring Principle of the Blood,
The caustic and the carbonated alkalis form deep red solu- Action of the
tions of this substance, which are extremely permanent. Sree
1. Solutions of pure potash, and of the subcarbonate, take ciple.
up a large proportion of the colouring matter of the blood.
The intensity of the colour of this solution, when concentrated,
is such, that it appears opaque, unless viewed in small masses, or
in a diluted state, when it is of a bright red colour.
2. Insoda and its subcarbonate the solution has more of a
crimson hue, which colour is extremely bright in its concen-~
trated state.
3. The solution in liquid ammonia approaches nearer to
scarlet than that in which the fixed alkalis are employed.
4. When these alkaline solutions are supersaturated with
muriatic acid, or with dilute sulphuric acid, they acquire a
colour nearly similar to the original solutions in those acids,
which have been above described.
5. Nitric acid, added in small quantities, or even to satura-
tion of the alkaline menstruum, heightens the colour of the
three compounds ; but when there is a slight excess, a tint of
orange is produced, which soon passes into bright yellow.
6. The alkaline solutions may be evaporated nearly to dry-
ness without losing their red colour ; during the evaporation of
the ammoniaca! solution, the alkali flies off, anda brown red
solution of the colouring matter in water remains.
Having ascertained the above facts respecting the colouring Examination
principle of the blood, 1 next proceeded to examine how far it ce ea Gina
was susceptible of entering into those combinations which are ing matter.
peculiar to other varieties of colouring matter.
These experiments I shall detail in the order in which they
were made.
1, Some
184
Alumine does
not form a
permanent red
with it,
Muriate of tin
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS.
1, Some pure alumine was added toa concentrated aqueous
solution of the colouring matter of the blood, and after twenty-
four hours, the mixture, which had been frequently agitated
during that period, was poured upon a filter, and the residuum
washed with hot distilled water,
The filti>ted liquor -had lost much of its original colour;
_ the alumine had acquired a red tinge ; it. was dried at a tem-
perature between 76° and 80°, during which it became brown.
2. Two hundred grains of alum were dissolved in four
fluid ounces of a solution of the colouring matter, similar to
that employed in the last experiment. The colour of the com-
pound was bright red. Liquid ammonia was added, and the
precipitate collected, and carefully dried. It was of a dirty
red, and after some days exposure to light, became nearly
brown.
From these, and other experiments, which I have not thought
it necessary to detail, it appears that alamine will not form a
permanent red compound with the colouring principle of the
blood; I was therefore next induced to employ oxide of tin.
3. Fifty grains of crystallized muriate of tin (prepared by
combined with boiling tin filings in miuriatic acid, and evaporating the
it,
and the acid
separated.
solution) were dissolved in four ounces of the solution of
colouring matter, which immediately assumed a purple tint,
and became afterward brown. It was diluted with twice its
bulk of water, and put aside in a stopped phial. On examin-
ing it three days afterward, a small quantity of a bright red
powder was observed at the bottom of the phial, which proved
to consist of the colouring principle combined with the metallic
oxide. A portion of this compound, which has been kept in
water for some weeks, has undergone no change of colour ; but
when dried by exposure to air, it loses its brilliant tint, and be-
comes of a dull red hue.
Jo a compound solution of muriate of tin and colouring
matter, similar to that employed in the last experiment, I
added a sufficient quantity of solution of pot-sh to decompose
the salt of tin, The precipitate thus obtained was collected,
and dried by exposure to the air of a warm room. It was of
a dull red colour, and has undergone no apparent change by
exposure to the joint action of light and air for three weeks.
4. Find-
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS. 185
4. Finding that supertartrate of potash exalted the colour Attempt to
of the blood, I endeavoured to form a compound of it with Bik eee
that substance and oxide of tin, and thus, in some measure, to trate of potash,
imitate the process in which cochineal is employed for the pro- ity nee
duction of scarlet dye; but although a bright red compound is
produced, when it is dried ata very moderate temperature its
colour becomes similar to that of the other combinations which
1 have described.
These experiments I repeated in various ways, occasionally The experi-
applying the salt of tin asa mordant to woollen cloth, linen, ™€ts varied.
&c. ; but the brilliancy of the colour was never permanent.
5. Having observed that infusion of galls and decoction of Oak bark used.
oak bark do not impair the colour of the blood, I conceived 45 2 mordant,
that solution of tannin might answer the purpose of a mordant,
as it is effectually employed by dyers in giving permanence to
some of their red colours.
I accordingly impregnated a piece of calico with decoction
of oak bark, and afterward passed it through an aqueous solu-
tien of the colouring matter of blood. When dry, it was
of a dirty red colour, nearly similar to that which would have
been obtained, had no mordant been applied : when, however,
an alkaline solution of the colouring matter was emploved, the
colour was equal to that of a common madder red, and as far as
I have been able to ascertain, it is permanent.
6. A solution of superacetite of lead was impregnated with Oxide of lead.”
the colouring matter of the blood. The compound was bright
red : no spontaneous change took place in it, and on the addi-
tion of an alkali a white precipitate was formed, the fluid re-
taining its former tint.
From this, and other experiments, in which it was attempted
to combine oxide of lead with the colouring matter of the
blood, it would appear, that there is no attraction between these
two substances,
7, The most effectual mordants, which I have discovered for Solution of
this colouring matter, are some of the solutions of mercury, ™°U'Y-
especially the nitrate, and corrosive sublimate. ,
Ten grains of nitrate of mercury, (prepared with heat, and Nitrate of the
containing the red oxide) were dissolved in two fluid ounces of pee Se
a solution of the colouring matter of the blood. After some
hours a deep red compound was deposited, consisting chiefly of
the
SO CHEMICAL RESEARCHES GN THE ANIMAL FLUIDS.
the metallic oxide combined with the colouring matter, and a
small portion of coagulated albumen. The remaining fluid
had nearly lost its red colour.
ef the black, The nitrate of mercury containing the black oxide produces
nearly similar effects, excepting that the colour of the com-
pound is of a lighter red.
Corrosive sub- When corrosive sublimate is added to the solution of the
panete, colouring matter, its tint is instantaneously brightened, and it
becomes slightly turbid from the deposition of albumen. If
this be immediately separated by a filter, the liquor which
passes through gradually deposits a deep red or purplish insolu-
ble precipitate, and if it now be again filtrated the liquid is co-
Jourless, the whole of the coiouring principle being retained in
the compound which remains upon the filter.
These salts By impregnating some pieces of woollen cloth with solution
inte mor- of nitrate of mercury, or of corrosive sublimate, and after-
: ward steeping them in an aqueous solution of the colouring
matter of the blood, Isucceeded in giving them a permanent
red tinge, unalterable by washing with soap ; and by employing
the ammoniacal solution of the colouring matter, calico and
linen may be dyed with the same mordant.
In these experiments I was much satisfied by the complete
separation of the colouring matter from its solutions, which
after the process were perfectly colourless.
VII. Some Remarks on the preceding experimental Details.
Analogy’ be- From the experiments related in the second section of this
eigpee mek paper, it appears, that sulphuric acid effects changes upon the
and curd of coagulum of chyle, similar to those which Mr. Hatchett has
mill, observed to result from the action of dilute nitric acid upon
the coagulated white of egg. This last substance, however,
is not convertible into gelatine by means of sulphuric acid,
whereas in these respects the curd of milk resembles that of
chyle : this circumstance, as well as the more ready solubility
of the coagulum of chyle in dilute, than in concentrated acids,
points out a strong analogy between these two bodies.
Sweet taste of The sweet taste of chyle naturally suggested the idea of its
chyle, containing sugar* ; but Iam not aware of any direct experi-
* Fordyce on Digestion, 2d Edition, p. 121.
ments
CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS. 187
ments which have demonstrated its existencé, and have there-
fore detailed minutely such researches as I have been enabled
to make upon the subject, hoping at some future period to ren-
der them more complete.
The experiments to prove the nonexistence of gelatine in No gelatine in
the serum of blood will, I trust, be deemed sufficiently decj- blood.
sive : they show, that that abundant proximate principle of
animals is not merely separated from the blood, in which it has
been supposed to exist ready formed, but that it is an actual pro- It is a product
duct of secretion. 8 aes
The proportion of iron afforded by the incineration of seve- The blood
ral varieties of animal coal is much less considerable than we irda a
have been led to expect, and the experiments noticed in the this not pecu-
fifth section show, that it is not more abundant in the colouring poles ae At
matter of the blood, than in the other substances which were
submitted to examination ; and that traces of it may be dis-
covered in the chyle, which is white, in the serum, and in the
washed crassamentum or pure fibrina.
The inferences to which I have alluded in the first section of The colouring
this paper are strongly sanctioned by these facts, and co- Pee eae
incide with the opinion, which has been laid befere the Royal ture;
Society by Dr. Wells*, respecting the peculiar nature of the
colouring principle of the blood, and support the arguments
which are there adduced.
That the colouring matter of the blood is perfectly inde- independent
pendent of iron, is, I conceive, sufficiently evident from its of iron :
general chemical habitudes, and it appears probable that it and probably
may prove more useful in the artof dying, than has hitherto oe Ss
been imagined, since neither the alkalis nor the acids (with ~ ra
the exception of the nitric) have much tendency to alter its
hue. The readiness, too, with which its stains are removed
from substances to which no mordant has been applied, seem to
render it peculiarly fit for the purposes of the calico-printer.
T have not extended these experiments, nor have I had them
repeated on a sufficient scale to enable me to draw more ge-
neral conclusions respecting the possibility of applying them
with advantage in the arts: this would have led me into too
* Phil, Trans, 1797.
wide
188 CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS.
wide a field, and one not immediately connected with the ob-
jects of this society : the subject, however, appears important.
So employed It is not a little remarkable, that blood is used by the Arme-
ating Arme- nian dyers, together with madder, in the preparation of their
finest and most durable reds*, and that it haseven been found
a necessary addition to insure the permanericy of the colourf.
This fact alone may be regarded as demonstrating the non-
existence of ivon as the colouring principle of the blood, for the
compounds of that metal convert the red madder to gray and:
black.
Menstrual While engaged in examining the colouring matter of the
fluid. blood, I received from Mr. William Money, house surgeon to
the general hospital at Northampton, some menstruous dis-
charge, collected from a woman with prolapsus uteri, and
consequently perfectly free from admixture of other secre-
tions. It had the properties of a very concentrated solution of
the colouring matter of the blood in a diluted serum, and
afforded an excellent opportunity of corroborating the facts
respecting tbis principle, which have been detailed in the pre-
ceding pages. Although I could detect no traces of iron, by
the usual modes of analysis, minute portions of that metal
may, and probably do exist in it, as well as in the other animal
fluids which I have examined ; but the abundance of colouring
Matter in this secretion should have afforded a proportional
quantity of iron, did any connection exist betweenthem. It
has been observed, that the artificial solutions of the colouring
matter of the blood, invariably exhibit a green tint when
viewed by transmitted light : this peculiarity is remarkably dis-
tinct in the menstruous discharge}. .
Rapid repro- I hope that some of the facts furnished by the above expe-
duction of per- riments may prove useful to the physiological inquirer : they
«et blood. account for the rapid reproduction of perfect blood after very
copious bleedings, which is quite inexplicable upon that hypo-
thesis which regards iron as the colouring matter, and may
* Tooke’s Russian Empire, Vol, III, p. 497.
tAikin’s Dictionary, Art. Dying, and Philos. Magazine, Vol. XVIII.
¢ I could discover no globules in this fluid ; and although a very slight
degree of putrefaction had commenced in it, yet the globules observed
in the blood would not have been destroyed by so trifling a change.
a perhaps
’
SPONTANEOUS RISE OF HOT LIE IN A PUMP. 189
perhaps lead to the solution of some hitherto unexplained
phenomena connected with the function of respiration. There
can, I think, be little doubt, that the formation of the colouring Formation of
matter of the blood is connected with the removal of a portion Hae a
ef carbon and hidrogen from that fluid, and that its various
tints are dependent upon such modifications of animal matter,
and not, as some have assumed, upon the different states of
oxidizement of the iron which it has beem supposed to contain.
r IV.
Remarkable Effects of the spontaneous Rise and Overflow of
heated Soap Lie in a metallic Pump. In a Letter from
R. B. with Remarks by W. N.
Zo Mr. Nicholson.
SIR,
WAS much pleased at the sight of your advertisement on Index to the
the wrapper of your last number, in which you promise an Pan
extensive Index to the whole Journal. JI have sent my sub-
Scription to the publisher ; and, as an old correspondent, who
has been your disciple from the very first, I think it incumbent
on me to look round for a few philosophical facts, and give my
assistance to your work as far as my ability may extend. I won-
der that ycu, who are known to be so intimately acquainted
with the practice of all our manufactures, have hever given us
a detail of what may be called the philosophy of a workshop.
Th the daily performance of manipulations, and the adoption Introductory
of expedients to ensure success, the manufacturer, by the chance remarks. ;
of events, and under the necessity cf making repeated trials,
is continually, and for the most part unconsciously, avail-
ing himself of the tenacities, the toughness, the brittleness, the
excitement and conducting of heat, the production and conden-
sation of elastic fluids, the statical and hydrostatical powers, with
the chemical energies of bodies, in such a variety of ways, as
would, and often does, afford the most certain instruction to
theorists, and not unfrequently the means of improving, in re-
turn, the very art under contemplation. I write these reflec-
tions as they flow from my pen, and asa kind of preface to a
fact
Philosophy of
a workshop.
190 SPONTANEOUS RISE OF HOT LIE IN A PUMP.
fact with which I find myself embarrassed. You have often
obliged your correspondents with disquisitions or investigations
in cases like the present. Whether this may lead to any useful
result beyond the mere fact, I know not: Iam sure you will
admit it to be curious ; and if you have not seen it, I beg you
will take the trouble to do so, and oblige me, and your other
readers, with your opinion of its cause.
Description of | Some time ago I visited an extensive soap manufactory, in
a boiler con- which there were several large boilers, each capable of holding
taing soap and : :
lies atun of soap. One of them was in a state to have the lie
drawn off from beneath the soap, which formed a fluid mass
between three and four inches thick, above a depth of perhaps
and a copper four feet of lie. I speak from memory throughout. There
pump to was a wooden back or vessel on one side to receive the lie, and
draw off the : ; Pi
lie from be. 2 °°PPer pump was lowered down into the boiler from a situa-
neath the soap, tion in which it had hung suspended above by atackle. I think
: the barrel of the pump might be about four inches in diameter,
terminating in a small copper cistern at top, with aspoutof about
. three inches bore, proceeding from one side of the cistern close to
its bottom. Ido not remember whether the pump was primed
ornot, but I think not, and suppose it may have had metallic
valves, and perhaps a hempen packing, instead of leather, which
could not be used with soap lie. The pump was, I doubt not,
lowered so as to rest on the bottom of the boiler, for it could
not else have been steady—and a workman began to pump.
When the hot Lhe lie came out ofthe spout in a stream which did not half
lie was first fill the bore, and it fell at no considerable distance from the
pumped, the f : Lite
effect was not Spout. During the whole experiment the soap and the lie ig
remarkable, the boiler appeared Jevel and motionless, neither circulating
nor showing any other sign of its high temperature, the soap at
but after afew top preventing even the steam from appearing. But after a
eee Lo ten few strokes the lie dashed out of the spout with a sudden
ratly. “ noise, and flew to the opposite side of the receptacle in a stream
hot, smoking, frothy, and filling the bore of the spout. The
workman left off pumping, and the stream continued with un-
ceasing violence and rapidity. I was astonished, and stood gaz-
ing at this striking effect, my mind being engaged with a mix-
ture of wonder at the phenomenon and puzzle at its continu-
and continued ing, when the apparent cause had ceased to act. But after a
considerable time, I turned to the assistants, and asked, “ how it
was
SPONTANEOUS RISE OF HOT LIB IN A PUMP: 191
was to be stopped *” Three men immediately came with
buckets of cold water, which they dashed against the pump, till on water
and the stream immiediatély slackened, but did not quite cease, eae
Tt was recovering strength, and I have no doubt would have pump.
arisen to its former violence if a fourth bucket of water had
not been brought in time, and dashed against the pump, upon
which it entirely ceased. These are the facts; to which I will
only add, that I think the immersed part of the pump was be-
tween three and four feet, and the spout might have been be-
tween two and three feet above the surface of the @uid in the
boiler.. Why hot soap lie, in these or any other circumstances,
should spontaneously rise and run with violence out of an aper-
ture more than two feet above its quiet level, is an event upon
which I cannot make eyena probable conjecture,
I am, Sir,
Your obliged Reader,
R. B.
Reply. W.N.
Some years ago, an application was made to me to report pro- Account of a
fessionally upon a pump, which was described to me; and it was Lee wine
added, that it produced the effect of raising water to a greater by suction
height, by what is called suction, than 33 or 34 feet. My report phen wean a4
was, that the pump was a bad one, and that it was incapable of
producing the pretended effect. Some time afterward, how-
ever, the same person called on me, and said, that the parties
who had commissioned him to apply to me had been deceived
by the inventor, who had made a small hole in the suction-pipe.
This led to observation on my part, that my general. conclusion
upon the merits of the pump would have been the same, if this
fact had been stated along with the others ; but that it would
have been accompanied with an indication of the time and
place where that trick had been played a century before ; which
does in truth, by mixing air with the column of water, enable
it, (because upon the whole lighter,) to rise to a greater height
than mere water ; but that the effect, taking height and quantity
into the consideration, would be less than that of a common
if pump.
a
192 SPONTANEOUS RISE OF HOT LIE IN A FUMP.
pump. T relate this, not because I infer the existence of any
trick in the remarkable fact so clearly and fully described by
, correspondent, but because it appears to indicate the solutien.
I have not, however, thought the analogy so perfect as to pre-
clude the necessity of visiting a soapwork, and of making an
experiment which seems altogether to clear up the subject.
The facts at the soap manufactory were precisely as he de-
scribes them ; and very striking indeed, notwithstanding my
expectation having been previously raised by R. B.’s description.
‘Tbe course of reasoning suggested by them were as follows ;
Inferences re- ‘Lhe lie and melted soap upon the surface, though strongly
see ae heated, were not sufficiently so to cause steam to be produced
continued rise Utder the pressure of four feet of fluid, addedtothat of the at-
and flow ofthe mosphere. But, when apart of this last pressure was taken oft
koa spe by the action of the p.mp, the fluid in contact with the bottom,
procaced i8- and immediately under the suction-pipe, was enabled to give out
nie ae: sie steam ; and the thin portion of fluid lying between the metallic
pump, and = edge of the pipe, and the bottom of the boiler, would be more
ie thin Patticularly so disposed (it being a well-known fact, that such
sp.-c between thin films are very readily converted into steam, as is strikingly
ae Bisse shown by heating water in a glass vessel with a small metallic
pipe, aod of ball or ptece of glass lying in it; most of the bubbles seeming
the boiler. to spring from these small nedieg? The progressive increase
This rendered
the column in Of steam will render the fluid in the pump-barrel frothy and
she pump lighter than the dense lie in the boiler; and as soon as the
Rgitek aed 2 reaction of its specific ‘gravity becomesso much as that a co-
to continue. Juimn of the whole length of the pump shall be lighter than a
‘column of the dense lie, of no greater length than answers to
the depth of the boiler, this last will predominate, and cause
the other to ascend without the aid of the pump. Now the
first developement of the steam was effected by the action of
the pump, in taking off atmospheric pressure ; but as soon as
the pump became very hot, and the steam very copicus, the
pressure of the inclosed column may be conceived to have become
much less than is requisite to allow the continued developement
of steam ; and the column being allowed to flow out sideways,
instead cfever rising to a counterpoise, the diminished pressure,
and also the afflux of the hot frothy lie, becomes permanent.
And the velocity of emission will be governed by the height to
which the lie is enabled or allowed to rise in the trough above
the
SPONTANEOUS RISE OF HOT LIE IN A PUMP. 193
the level of the spout. I am greatly disposed to think the
condition that the heated lie must all pass between the
two hot metallic bodies, the lower edge of the suction-pipe, and
the bottom of the boiler, isof great consequence to the whole
. effect.
In order to bring the subject in some measure to the test of elaine
experiment, I took a tubular glass vessel, ten inches long, and Cie ehek ia
one inch internal diameter, having a small enlargement, or foot which an up-
to stand upon, asa chemical measure, By a smart stroke with oe Legis
the end of a pointed file, I drove the bottom in, by making a ced, stood
large hole in the middle without breaking the other parts. In io fle 3
this state it was capable of standing on its bottom as before. A
tin vessel with a flat bottom was then filled to the depth of three
inches with water, and the glass vessel being set upright in the
water, the whole was placed on the fire. As soon as the liquid
began to boil, the bubbles were most plentiful in the tube, and
the water stood at rather less than three quarters of an inch
higher in the tube than in the exterior vessel. When the boil- Particular cir-
ing was very rapid, the difference was rather less, and when the hecuert a
_ tube was raised a little from touching the bottom, the diffe- ment.
rence ceased. Upon taking the tube out, and letting it cool,
and then setting it as before in the boiling water, the difference
or rise did not take place, nor was any boiling seen within the
tube till after the lapse of about half a minute ; and upon in-
verting the tube, so that its mouth touched the bottom of the
tin vessel, and the foot was uppermost, the water within it did
hot stand so high, nor boil so fast, as when the contrary position
was adopted, And lastly, the difference appeared rather more
considerable when the boiling was moderate, than when the
whole mass of the fluid was full of steam-bubbles by rapid
ebullition. Inferences.
Though the preceding experiment is not so apposite and a ceprbaT
. ° . : oni
conclusive as it might have been made, by using a greater depth Cf the water
of asaline fluid, and allowing a side aperture for the same to inthe tube
flow out as inthe pump ; yet it appears to me to show with aerate
sufficient precision, 1. That the column of fluid in the tube was produced most
of less specific gravity, from the greater admixture of steam- cian ey bt
bubbles, than a like column of the exterior heated fluid, and er part of the
: ry : : ti/be, and bot-
therefore stood higher. 2. That the excessive quantity of steam Yorn. a
was produced from the thin film of water between the foot of sel.
Vor. XXXII, No. 153.—-Novempber, 1812, O the
194 ACTION OF CHLORINE ON OIL OF TURFENTINE.
the tube, and bottom of the tin vessel’; and that less steam
being produced when the mouth of the tube was downwards,
and the film less extensive, the internal fluid did not stand so
high. 3. That it would have stood higher, if there had been
a side aperture ; because this would have caused a rapid access
of new water to the film, and carried all the bubbles: inwards.
4. That upon raising the tube, the film lost its thinness, and the
effect ceased. 5. That the effect was less when the exterior
fluid was rendered lighter by strong boiling, which filled it with
steam-bubbles. 6. And thatthe cold tube produced no effect,
but required to be first heated to the boiling point, before any
steam could be produced in contact with it.
SSE
V.
/
On the Combination of Chlorine with Oil of Turpentine. in a
Letter from Mr. R. Porrert, jun.
To Mr. Nicholson.
SIR, Tower, Oct. 2, 1812.
HAVE just read Mr. John Davy’s paper, published on the
Retprence ae Ist of last month, in No. 151 of your Journal, on the.
Mr. J. Davy’s combination of chlorine ; and my attention was particularly en-
ir an ort gaged by that part of it in which he mentions an experiment
of turpentine. of his on the action of Libavius’s liquid, or stannanea, on oil
of turpentine, and states, that the oil became viscid, less volatile
than before ; that it had little taste or smell ;, and that. its solu-
tion in alcohol, when dropped into water, occasioned a,cloudi-
ness in that fluid.
Analogous ex- This experiment of Mr. J. Davy’s recalled to my mind some
periments for- analogous experiments which I.made long before his, and in
merly made . nee ae
by the author, which I formed, as I have some reason for believing, a similar
fluid to that obtained by Mr. J. Davy ; and as that gentleman
expresses a wish, that a subject so curious might engage the
attention of chemists, I think this a fit opportunity for request-
ing your insertion of those experiments in your valuable Jour-
nal. Imperfect as they are, they may thus afford some infor
mation, and will become more generally known than they, can
be by the communications of them which I have made in, con-
versation
ACTION OF CHLORINE ON OIL OF TURPENTINE: ig
versation with my chemical friends, and in a lecture on chlo-
rine and muriatic acid, which I delivered to the Mathematical
Society on the 22d of February last.
To avoid the suspicion, that any part of what I have now to Date of the
communicate is borrowed from Mr. J. Davy’s paper, I think is Seah
it best to transcribe, verbatim, my memorandum of the first
experiment, in°which I combined chlorine with oil of turpen-
tine. It was performed some time between the 24th of July,
and Ist of November, 1808, those being the dates of the ex-
periments immediately preceding and: following that which I
am about to transcribe, and which in my memorandum I had
omitted todate, The following is the copy of the memoran-
dum.
“< Experiment with Oil of Turpentine.
a! Wishing to ascertain the effect of oxymuriatic gas on oil of Oxymur. gas
“turpentine, I caused the vapour of the latter and the oxymu- nen oft the
“* riatic gas to pass together through a glass tube conducting into state of vas
*‘aglass receiver. There was formed by this process a very Py, ti a aa
** heavy white oil, which sunk immediately in water, was as was fornted,
*¢ thick as otta of roses; smelt and tasted very much like nut- &c-
“megs, but communicated rather a more caustic sensation to
“‘the tongue. I did not observe any disengagement of gas,
** arising from the chemical combination that was going on;
_ very little was expelled from the receiver, and that, I believe,
‘* was only oxymurtiatic. I did not collect and examine it, to
‘© ascertain whether any other gas was present, but the smell
«« proved that that gas was evolved; andas it only took place
«© when the extrication of the oxymuriatic acid from the mate-
“rials that produced it was violent, there is some reason for
*€ thinking it was not contaminated with any other gas, “which
** might be supposed to be formed from the oil of turpentine.
*¢ The change produced on the oil of turpentine in this experi-
“ment is very great, from an exceedingly light and thin fluid
** to a very heavy and viscid one, differing likewise totally in
** its smell and taste.”
[have since formed a similar fluid by passing a large quantity Repetition of
of chlorine gas through a small quantity of oil of turpentine. the experi-
The product of this experiment I exhibited to the Mathema- ;
— ao during the lecture before mentioned ; and J havea
; O2 little
196 ELECTRICAL EFFECTS PRODUCED BY FRICTION.
little now remaining in my possession. Its taste is the same as
of that obtained in the first experiment ; viz. a bitter aromatic,
uniting the flavour of hops with that of nutmegs. I have re-
marked, that the flame arising from its combustion is edged
with green.
Compound of Still more recently, viz. on the 15th of January last, I ob-
Seay with tained a compound of this fluid with sulphur, by acting on oil of)
turpentine by Dr. Thompson’s sulphuretted liquid, or sulphu-
rane. This compound is decomposed by solution of potassa,
which dissolves the sulphur, and separates the peculiar fluid;
which then exhibits, as far as I have been able to judge, all the
characters of that formed by the direct combination of chlorine
with oil of turpentine. This experiment, I recollect, appeared”
to me, at the time that I made it, as very favourable to the
opinion formed by Sir Humphrey Davy of the nature of Dr.
Thompson’s sulphuretted liquid.
Whether this I cannot positively say whether the peculiar aid: formed in’
pe the three experiments just described is identical with that
that of Mr, produced by Mr. John Davy from the mutual action of stan-
John Davy. — nanea and oil of turpentine. Reasoning from analogy would
induce me to conclude that it is; but some differences in our
descriptions of those fluids oblige me to suspend forming a de-—
cided opinion, until the fluids themselves have been compared.
I am, Sir,
Your most obedient Servant,
R. PORRETT, Jun.
SaaS
VI.
On the Electrical Effects produced by Friction between Bodies. In
a Letter from J. A. De Lue, Esq. F. RB. S.
To William Nicholson, Esq.
SIR,
N my former papers I have communicated to you my ‘Te-
Reference to marks on Dr. Maycock’s electrical system; and I come
former papers. now to his paper in your Journal, No. 144, concerning the
production of electrical excitement by friction. This paper con-
cludes by the following very judicious remark, which induces
me -to offer here to-him my ideas on the same subject,
(79 It
ELECTRICAL EFFECTS PRODUCED BY FRICTION. 197
** It will afford me much pleasure (says Dr. Maycock) Theory of
** should these observations eall the attention of your readers to apes ne
“the theory of electrical excitement. I trust that, while we are serves atten-
** successfully employing the powers of electricity in chemical #™.
‘analysis, we shall not altogether neglect to investigate the
““means by which these powers are called forth, and the laws
§' by which their action is regulated. It has, with much in-
justice, been objected to theoretical pursuits, that they lead
““ to none of the practical advantages, which interest the happi-
ess of society. The remark is indeed true, if applied to
ticular discoveries ; but these are to be considered only as
e elements from which physical science first took its ori-
in, and by which it is daily nourished and supported. Let
‘it never be forgotten, that our most perfect instruments,
** those which promote no less our comfort, than they tend to
‘advance our intellectual improvement, are the invaluable
** fruits of philosophy.” Journ. vol. XXXI, p. 309.
1. In quoting this passage with approbation, I cannot, Sir, wets shea
but express again my regret, that Dr. Maycock appears to have amined. ai
no knowledge of my papers in your Journal ; for they might
have given him the opportunity of useful examinations between
us. For instance, in your No. 126, for January, 1811*, is my
paper under the title of Experiments, showing the effects of
Friction between bodies; which experiments might have af-
forded him what he wishes to find in your readers, viz. some
remarks to be compared with his theory. But if he reads my
_ present paper, there will be only a little time lost, and the ex-
amination may now be effected more vii between us
in your Journal.
2. Dr. Maycock’s system on the effects of friction is de- Dr. Maycock’s
rived from his opinion, which, in my former papers, I have Een oe
proved to be unfounded, viz. that the electrical effects produced
by the association of two proper metals appeared only when
they came to be separated. Had Dr. Maycock known these
papers, he certainly would have thought it proper to answer.
me, before he took his system asa principle in explaining the
effects of friction, as he does thus in vol. XXXI, p. 305. ‘It
«© must be obvious, that, while we are drawing one body over
* Vol, XXVIII, p. 1.
another,
This theory
difficalt to
prove,
Principal facts
relative to ex-
citement by
friction, ac-
cording to
him.
ELECTRICL EFFECTS PRODUCED BY FRICTION. )
** another, a number of points in the surface of the rubber are
** first brought into contact with a corresponding set of points
“* in the surface of the body rubbed ; that they are then sepa-
** rated from them, and brought into contact with another set of
*€ points; and so on, until the one body has passed entirely over
** the other. Now, at each separation, if the bodies be of different
‘* kinds, whether conductors or nonconductors, the general
‘‘law, we have stated, must operate, and opposite electrical
** states must be excited in the separated particles. So far,
** therefore, the excitement by friction, and the excitement by
** contact and separation, appear to be referrible, in a gent ra
** manner, to the same principle. Weshall now proceed to a ”
** more particular consideration of the subject.” “a
. To this consideration I shall soon come; but I must first
pis that it would be very difficult to prove that theory by
ascertaining the effects of the friction in different points of the
rubber and the Lody rubbed, in order to find out their progress.
We see, upon the whole, that one is become negative, when
the other is made positive; but nothing can indicate whether
‘these effects are produced during the contact, or only at the
separation. ‘Therefore the decision of this point must pro-
ceed from other phenomena, and Dr. Maycock affords me an
opportunity of discussing this point by the passage which fol-
lows that above quoted.
“* The principal facts (he says) relative to the excitement of
““ bodies by friction, may be expressed by the five following
‘< propositions. 1. To produce excitement by frietion, it
‘* is essentially necessary that one of the bodies employed in
‘«the operation be of the class of electrics. 2. Iftwo electrics,
“¢ oy an electric and an insulated conductor be employed, the one
“ body will, after the operation, indicate an electricity opposite
«to that which is indicated by the other. 3. The effect of
«* friction performed with one combination of dissimilar bo-
“dies is different from that which is produced by any other
‘combination. 4. The friction of two bodies, simélar in all
“* respects to one another, produces no excitement. 5. If the
‘‘ rubber of an electrical machine be insulated, only a very
- “ slight charge can be accumulated in the prime conductor ;
«© and, under such circumstances, the action of the machine
*€ soon ccases altogether.”
5. J
4
ELECTRICAL EFFECTS PRODUCED BY FRICTION. 199
5. I shall first observe, that, had Dr. Maycock read my paper Errour in the
on the effects of friction, to which I shall here refer on many iatoubaitpes psy
points, he would have seen the errour of the first electricians in trics and con-
their distinction of bodies, which ke continues to admit, that of (¥°t°"
electrics opposed to conductors ; as if the former only had the
faculty to be electrified by friction. With respect to electricity, all bodies con-
there is no other distinction than that of more or less conductors, ae oh ous
which explains all the phenomena. From the property of ab- put on some
solute nonconductors, as are resincus bodies, whatever change the effects are
is produced in the electrical state of their surface, either by ny ia ie
ictton, or by communication with an electrified body, it is not
pagated on them ; and this is their only distinctive property
ith respect to electrical phenomena. The difference, there-
fore, between these bodies, and the imperfect nonconductors,
is this ; that the changes produced on some points of the latter,
either by friction, or by communication with an electrified body,
are propagated on their surface, slowly on some, as glass, or
‘almost instantly on the Lest cenductors, such as metals.
6. From this determination of the effects of the different Motion of the
conducting faculties of bodies, united with that of the nature eee ata
of the electric fluid, which Dr. Maycock has not thought ne- bode,
cessary to investigate, I derived in thesame paper (pp. 3 and 4)
the following theory of the effects of friction, which is to be
compared with the phenomena. ‘* The electric fluid resides
“ on all terrestrial bodies, every particle of air included ; being
“* retained upon them by a mutual attraction, which, however,
*« differs in degree ; some attract the electric fluid only when it
* comes into contact with them ; but then it adheres strongly
“f to the parts which receive it, or moves but very slowly along
“their surface ; which therefore are nonconductors: others
“* receive it at more or less distance, and it is propagated more
** or less rapidly along their surface. Glass, though absolutely
“< impermeable to the electric fluid, permits it to move with a
«« sensible progress along its surface.”
7. After these definitions of the mature of the eleciric fluid, Theory of the
and of its motions along different bodies, I thus define the effects of fric-
effects of friction, connected with these premises. ‘“‘ Friction shige
** excited between two bodies, has no other effect than that of
** disturbing the natural equilibrium of the electric fluid, which
“€ equilibrium tends always to be produced among all bodies,
accords
200
Motive and
plan of Mr.
De Luc’s ex.
periments,
The appara-
tus,
‘found positive, as having acquired a proportional quantity o
ELECTRICAL EFFECTS PROPUGCED BY FRICTION.
** according to its actual, but local (in a certain extent) quanti-
«* ties on them, and in the ambient air. If both the bodies which
“exercise friciion on each other are good conductors, the equi-
** librium being constantly restored, this disturbance is not
“* perceived: but if one has more disposition than the other to
‘‘ attract the electric fluid thus agitated, with the faculty of
“transmitting it to its remote parts; when the bodies are
** separated, either suddenly, or in general before the equili-
‘* brium of the electric fluid is- restored between them, one is
“ this fluid, greater than the ambient air, and the other negative,
*‘as having lost that quantity.” This is the theory of
effects of friction, which, in the same paper, I compare wi
direct experiments : but before I come to that comparison, I
must explain the general plan of those experiments, and its
motive,
8. The obscurity which reigned on the effects of friction pro-
ceeded from a circumstance wanting in most of these experi-
ments; they require the insulation, not of one only of the
bodies, but of loth, either conductor or nonconductor; else
the whole of the reciprocal effect cannot be discovered. I had
found this necessity by many experiments made with, large
bodies, with which I could exactly follow the motions of the
electric fluid. But I could not suppose it easy for every experi-
mental philosopher to procure this apparatus, which I had
partly constructed myself; therefore I attempted to produce a
small apparatus, containing in itself all the parts of the large
one, which might easily be obtained by every experimental
philosopher ; and having succeeded, I thus introduced, in the
same paper, this new plan of experiments on friction, -‘* Mr.
«© Cavallo has given a table containing the results of his experi-
§* ments of this kind, wherein is found, that certain bodies
“become either negative or positive, according to those by
* which they are rubbed. However, there remained to le known
“* what effect was produced on each of the bodies which exercised
“* that friction. This has been one of the objects of my expe-
*‘riments; for which purpose I kept zmsulated both bodies,
* exercising friction on each other, applying electrometers to
both,”
g. Then. follows, in the same paper, the description of the
appa;
ELECTRICAL EFFECTS PRODUCED BY FRICTION. CO]
apparatus with which these experiments were made : its figure,
which is at the head of the paper, is half the size of the appa-
ratus itself; and it may be seen, in that figure, that itis, in
fact, avery small electric machine, with a revolving part and a
rubber: but it is so constructed, that both these parts may be
easily changed, for producing friction between different bodies,
the effects of which are always shown by the gold leaf electro-
meters. 1 do not think it necessary to compare directly every
part of these experiments with Dr. Maycock’s theory ; he is
o intelligent, that, had he read my paper, he would have
‘found himself those relating to the objects on which we dis-
t; therefore, I shall only indicate briefly some of these
10. The fourth proposition of Dr. Maycock’s theory, above Dr. Maycock’s
quoted, is the following : “‘ The friction of two bodies, similar ee ‘
‘im every respect to one another, produces no excitement.” by experi-
This is the immediate consequence of his theory, but is con- ™*"*
trary to mine: here, therefore, is afforded a criterion between
them ; and he might have found the decision in my paper.
There, after having explained my theory,—that, in the friction
between two bodies, which operation agitates the electric fluid
on their surface, the body which is the most disposed to seize
upon that fluid, and to transmit it to its remote parts, becomes
positive, and the other negative,—I added: “ This holds, not
“only between bodies of different natures, but even between
“‘ the same kinds of bodies, if one be made to pass in length
© over one part only of the other. This effect cannot be ob-
«« served with perfect conductors, as on them the equilibrium of
*« the electric fluid is instantly restored; but there is a known
“* experiment with twe pieces ef the same suk riband, in
“« which, by making one piece pass rapidly in length on one
“« part only of the other, the former becomes positive, by car-
* rying off some electric fluid from the latter, which thus is
** rendered negative, by losing that fluid.’
11. These experiments I have repeated many times; by Experiment
using pieces of wide and strong sik riland about a yard long, tea ge ate
at the extremities of which were’ fixed proper pieces of wood, :
to keep them stretched; one being held very steady, while
‘somebody made the other pass rapidly on one part of the fore
mer: then applying each of them instantly to the top of a
gold
202 ELECTRICAL EFFECTS PRODUCED BY #RICTION.
gold leaf electrometer, the riband which has moved is found
. positive, and the other negative. I must observe, that this ex-
periment cannot succeed, but when the air is very dry, com-
monly in winter, at the time that a divergence produced in the
gold leaves by any cause is long preserved ; else the effects pro-
duced on the ribands is soon dissipated.
with glass, 12. I have produced the same effect by the friction between
other bodies absolutely similar to one another, namely, glass
and glass ; as may be seen in Exp.3 of the same paper. The
revolving body was a glass cylinder, and the rubler a piece of,
the same gluss. Now, the revolving glass, as the riband )
which passed in length over the other, carried off some electric
Jluid from the immovable rubber, and immediately transmitted
it to the prime conductor of the small machine; so that, at
every revolution, the gold-Jeaves connected with it increased in
divergence, and at last diverged much as positive. *
carrer Ai 13. All the experiments related in that paper demonstrate
stances, the same theory concerning the: effects of friction; but I shall
only indicate them shortly, as the details may be seen in the
paper itself. In Exper.1, a brass rubber acting on a glass
revolving cylinder, the brass became negative, and the glass
was made positive. ‘This is the same effect produced by a me-
tallic amalgama laid on the rubber of the electric machine. —
In Exper. 4, a sealmg wax rubber applied on the same re-
volving glass cylinder, the sealing wax becomes negative, and
the glass is positive. The latter, as being a better conductor,
carries off a greater part of the agitated electric fluid. In
Exper..5 is seen a very singular case. Having used for rubber
apiece of India-rubler, on the same revolving glass cylinder,
according to the degree of pressure, sometimes the glass be-
came positive, and the rubber then was negative; at other
times the former was negative, and the latter positive. This
case shows, that, between the same lodies, when they have a
disposition to adhere to each other, friction 'may have inverted
electrical effects, according to the degree, or parts, that the
adhesion takes ‘place.
Ametal,when 14, come now to very remarkable changes in the electrical
insulated, ren- ae 4 5
dered either ffects of friction, according ‘to other circumstances. It has
positive or ne- been seen above, in Exper. 11, ‘that:a brass rubber, applied ‘to
gative, accor the revolving glass cylinder, became negative, and the glass
ding to cir-
cumstances, ‘ wap
ELEOTRICAL EFFECTS PRODUCED BY FRICTION. 903
Si
~
was made positive. But in Exper. 6, the same brass rubber
being applied to a revolving cylinder of sealing wax, the latter
was made zegative, and the brass became positive. Thus,
therefore, brass, though the best conductor as a metal, when it
is insulated, and thus retains the effect produced on it by frie-
tion, shows, that it is rendered either positive or negative,
according to the body which exercises friction upon it.
15. With respect to sealing wax, which is our common test Sealing wax
to discover whether our electroscopes indicate the positive or ses lg Uae
negative state by their divergence ; because sealing wax, when Agi cL rages
pbbed with the hand, or some cloth, becomes zegative; tain bodies.
per..7 proves, that sealing wax itself is made positive by
riction with certain bodies. In this experiment, the same
revolving cylinder of sealing wax, which before was become
negative by a brass rubber, was made strongly positive by the
India-rubber. ’
_ 16. Exper. 8 is farther illustrative of these differences of Other experi-
electrical effects produced by friction on the same bodies, ac- re ditigiear
cording to those which exercise frictian on them. The object effects on the
of that experiment is one of the Jndia-Leads, the size and S2™¢ bodies.
colour of a cherry, used by Indian women in necklaces or
other ornaments, which consist of an inspissated vegetable oil.
One of these deads I made to revolve by a glass axis, and
applied to it successively a brass rubber, and a sealing wax one :
the brass rubber rendered it negative, and became itself posz-
twve ; ‘but the sealing wax rubber made the same bead positive,
becoming itself negative.
16. All these experiments prove, first, that the distinction Deductions
between electric and anelectric bodies was illusory; that none, ae ae id
in their natural state, are either positive or negative. With
respect to friction, these experiments demonstrate, that this
operation has no other effect than that of disturbing the equili-
brium of the electric fluid on their surface, one of which,
according to circumstances, retains more and the other less of
that fluid. F
17. If Dr. Maycock happens to see this abstract of the ex-
periments contained in my former papers in your Journal, I
think he may find, that every thing belonging to electrical
‘phenomena is much clearer than he had imagined : he, however,
encouraged natural philosophers to collect all the known facts
td under
=
204
Supposed ob-
scurity with
respect to the
action of the
galvanic
trough.
Dr. Maycock’s
experiments
with it.
Attempt to
explain the ap-
‘ parent incon-
sistency in
them.
ELECTRICAL EFFECTS PRODUCED BY FRICTION.
under some theory, as tending to advance our intellectual tm-
provement ; and he will now judge whether I have accom-
plished this purpose.
18, The last part of his paper will lead us to another field,
where he finds much obscurity, but on which I think light will
appear. This part relates to what he calls the galvanic battery,
saying: ‘ that all the opinions, which have been proposed to
“* account for it, are unavoidably hypothetical, and indeed very
** unsatisfactory ; and that, therefore, every fact, which relates
“to it, deserves attention, although its application may not be
** clearly perceived.” This gives me hope that he will con- y
sider what I shall here explain; expressing, however, again”
my regret, that he has not known my paper in your Journal on
the galvanic pile, an apparatus in which the causes and effects
may be easily followed ; but I hope to make them clear, even
in the apparatus of troughs, the only one Dr. Maycock seems
to have used. I therefore shall copy first what he says of his
experiments. '
*« J filled one of the new porcelain troughs with an acid fluid,
“so that the metallic plates, and their connecting arcs, were
“* completely covered. In this state, a trough of 10 pairs of
« plates, 3 inches square, decomposed water very rapidly.
‘Anxious to know how far the division of the trough into
“* cells is requisite, I placed the metals, connected by the Lar,
** in a trough without partitions, and filled it with the same
«kind of acid,—but no action ensued. The action which
“* took place in the first experiment appears smconsistent with
‘© all our theories ; and it seems not a little curious, sincea
“communication between the cells is not an impediment to
“* action, that no action was evinced in the second experiment.
“* It would afford me much pleasure, should these observations
‘‘ call the attention of your readers to the theory of electrical
“* excitement.” It has certainly been the case with me, and I
shall now explain how I find his experiments consistent with
each other, and also with my theory.
19. In the first of these experiments, the trough with parti-
tions produced a series of ten distinct pairs of the two metals,
which, being formed of plates 3 inches square, were sufficient
to produce the effect described ; as the liquid was a conductor,
whieh transmitted undisturbed the effect of each pair to the
next
ELECTRICAL EFFECTS PRODUCED BY FRICTION. 205
next on both sides; as does the wet cloth in the galvanic pile.
But when the plates were entirely immersed up to the lars in
the liquid, the latter being a conductor which embraced the
whole, every difference between the metals in each intermediary
pair was destroyed, and the effect was reduced to that of one
single pair.
20. This will be shown by an analogous experiment, which, Apparatus to
for another purpose, I made some years ago at Berlin, related Bs dag at
in p. 253 of the 2d vol. of a work under the title of Traité of the elec-
élémentaire sur le Fluide électro-galvanique, published at Paris, page.
yin 1804, [I had then in view the phenomenon of the electric
‘eel; that fish which produces the shock while in water. I tried
to imitate that eel by a galvanic piie, composed of 30 groups
of zinc and silver, separated by pieces of cloth imbued with
salt water. These groups were held together by 3 glass rods,
so kept together as to leave no projection outwards, and resem-
bling so far an electric eel. With this pile I made the follow-
ing experiments :—1. It being held upright, I received a strong Experiments.
shock from it: having applied to it the usual glass tube with bil satnis
water, the gasses were produced in that tube. 2. I laid the pile
on my table ;. it continued to produce the shock. 3. I laid it in
a narrow wooden trough, with a little water at the bottom;
the shock was less. 4.1 poured successively more water into
the trough: in proportion as the water rose round the pile, the
shock was less ; and at last, when the water covered it entirely,
not only there was no more shock, but, having applied be-
tween its extremities a glass tule with water, no gas was
produced. ‘The electrical eel, therefore, has no perceptible ana-
logy with the galvanic pile, though tue effects are similar.
This, I think, will show Dr. Maycock the manner in which .
his two experiments are reconciled with each other, and are
consistent with my theory. It will also give me much pleasure,
sir, if Dr. Maycock, finding any objections to my explanation,
will. transmit them to me through your valuable Journal ; for I
have a great regard for him, though not personally acquainted
with him.
I have the honour to be,
Sir,
Your obedient, humble Servant,
J,A. DE LUC.
Windsor, October the 5th, 1832,
206
Vil.
METEOROLOGICAL JOURNAL,
BAROMETER.
1812. | Wind.| Max.
Aus. 29\N W} 29°99
30IN- E| 30°04
311 N | 30°15
E| 30°18
E| 30°15
W| 30°10
E} 20°95
E} 29°06
E| 30°07
E} 30°09
8} E ‘| 30°07
95 _ E| 29:99
10} S | 30°17
11\IN W{| 30°28)
25| Var. | 30°04
26} W { 30:07,
30°28
Min.
29°98
29°99
30°04
30°15
30°10
20°95
29°89
29'89
29°96
30°07
29°97
29 97
29°95
30°17
30°22
30°14
30:07
29°94
29'82
| 29°82
20°06
30°12
30°03
29:97
29°91
| 29°93
29°95
_ 29°99
30°04
Med.
29'985
30 O15
30°095
30°165
30°125
30'025
2.9'920
29'925
30°015
30°080
30'020
2.9980
30060
30'225
30240
30'160
30°125
30'005
29°880
2.9890
30080
30°130
30075
30°000
29°930
2.9'940
30005
30015
30'055|
THERMOMETER.
Max. | Min.
53:
(| cena | eeeemeemee | omens osc | ESD | emcee
Med. | Evap. } Rain.
58'0
ee
— |} ‘16))
— } ‘14
‘28 @
“£1
— €
"53
—s "15
‘48
— {34h
mh
23
29'82| 30:040| 73 | 34 {54:93 | 2°50] -79
*
The observations in each line of the table apply to a period of twenty-four hours
beginning at 9 A. M. on the day indicated in the first column,
the result is included in the next following observation.
A dash denotes that
REMARKS,
METEOROLOGICAL JOURNAL.
REMARKS.
Eighth Month. 30. Very showery. Between 4 and 5 p.m.
a sudden tornado (as it seems by the description given) crossed
the village in a direction from N. E to S. W. which left behind
it considerable traces of its violence : a large quantity of wheat
in sheaves was carried over a hedge into a neighbouring field :
a fence was levelled, and about seventy oak hurdles torn out of
the ground, some of which were seen tumbling over in the air,
and fell at two hundred yards distance.
Ninth Month. 12. Misty morning : much dew. 13, 14, The
same in the evening, a dense stratus reflecting on its surface
with much brilliancy the orange colour of the western sky.
15. Hoar frost in the pastures : a stratus at night as before,
the wind coming about to the eastward soon after it was formed.
16. Cirrus with cirro-stratus and cumulus, 17. Rain most of
the afiernoon ; a rich crimson tinge on the lower surface of the
clouds at sunset, 18. At sunset the sky was extensively co-
loured with orange, surmounted by a distinct blush of red :
the colour was reflected in the E. horizon. 19. a. m. much
hoar frost. 22. a.m. clear at first, but soon overcast, with rain:
25, Hoar frost. 26. Cirro-stratus.
RESULTS.
Easterly winds prevailed the fore part, and westerly the latter part, of
this period,
Barometer : highest observation 30°28 inches ; lowest 29°82 inches,
Mean of the period 30°040 inches.
Thermometer : highest observation 73° ; lowest 34°.
Mean of the period 54°93°.
Evaporation 2°50 inches, Rain 0°79 inches.
PLarstow. L. HOWARD.
Tenth Month, 8, 1812.
122)
©
=
Angles of
crystals cor-
rected by the
PRIMITIVE CRYSTALS OF SOME CARBONATES.
VIII.
On the primitive Crystals of Carbonate of Lime, Bitter-Spar;
and Iron Spar. By Witt1am Hypz Woxtaston, M. D.
Sec. R. S*.
HEN I formerly described to the Seciety a goniometert
upon a new construction for measuring the angles of
author’s goni- crystals, I expressed an expectation, that we should thereby be
emeter.
Haiiy’s accu-
racy in gene-
ral surprising.
The same pri-
mitive form
assigned by
him to three
substances;
Identity of
composition
should accom-
oe identity
gure.
enabled to correct former observations made by means of less
accurate instruments. I took occasion to mention one instance
of inaccurate measurement in the primitive angle of the com-
mon carbonaté of lime ; and I have had the satisfaction to find
the necessity of a correction, in that instance, confirmed by
Mons. Malus, and admitted by the Abbé Haiiy, in a workt
published nearly at the same time.
It is by no means my design to detract, in any degree, from
the merit of that justly celebrated crystallographer, to the sur-
prising accuracy of whose measurements I could, in various
instances, bear testimony. I hope, on the contrary, that in
bringing forward two more observations similar to the pre-
ceding, and intimately connected with it, I shall offer what
will not only appear interesting to crystallographers in general,
but will be peculiarly gratifying to the Abbé Hauy.
In his Traité de Minéralogie, and again more recently in
his Tableau Comparatif, the same primitive form is assigned
to three substances very different. in their composition to car-
bonate of lime, to magnesian carbonate of lime (or bitter-spar)
and to carbonate of iron.
It has been objected to Mons, Haiy, that HPs ah to his
method identity of form should be accompanied by identity of
composition, unless the form were one of the common regular
solids. For though in thiscase any geometrician would readily
admit it tobe very probable, that many different substances
might occur in assuming the same form of cube, of octo-
* Philos, Trans, for 1812, p. 159.
¢ Philos. Trans. 1809, p. 253 ; or Journal, vol. XXV, p. 192.
¢ Tableau Comparatif ales Résultats de la Crystallographie et de PAna-
lyse Chimique.
-
B hedron,
PRIMITIVE CRYSTALS OF SOME CARBONATES. 209
hedron, or of dodecahedron, &c.; there does not appear a cor-
tesponding probability, that any two dissimilar substances
would assume the same form of a particular rhomboid of 105°
and a few minutes, to which no such geometric regularity, or
peculiar simplicity, can be ascribed.
But though so accurate a correspondence, as has been ing ee of
hitherto supposed to exist in the measures of the three carbo- Mri
Nates above-mentioned, might be justly considered as highly Jar, but not
improbable, no degree of improbability whatever attaches to aie wei
the supposition, that their angles approach each other by some
difference, so small as hitherto to have escaped detection.
And this, in fact, I find to be the case.
Since the angles observable in fractures of crystalline sub- Least measure
stanees are subject to vary a little at different surfaces, and aoe
even in different parts of the same surface (as is evident from ployed: by the
the confused image seen by reflection from them) I shall not @thor.
at present undertake to determine the angles of these bodies
to less than five minutes of a degree. ‘This, indeed, is the
smallest division of the goniometer that I usually employ, as
I purposely decline giving so much time to these inquiries, as
would be requisite for attempting to arrive at greater precision.
The most accurate determination of the angle of carbonate shee ais
of lime is probably that of Mons. Malus, who measured it by Ss re
means of a repeating circle, and found it tobe 105°5’. And
this, indeed, is the result to which I formerly came by a diffe-
rent method*. If it differ in any respect from this quantity, I
am inclined to think that it will more likely be found to be
deficient by a few minutes, than to exceed the measure here
assigned ; and accordingly to differ still more widely from those
angles which I am about to mention.
In the magnesian carbonate of lime, or bitter-spar, the pri- of bitter-spar,
mitive form is well known to be a regular rhomboid, as well
as that of carbonate of lime, and so nearly resembling it, as
to have been hitherto supposed the same. I find, however, a
difference of 1° 10 in the measures of these crystals; for that
of the magnesian catbonate is full 106°, as I have observed
with uniformity, in at least five different specimens of this sub- ‘
stance, obtained from situations very distant from each other.
* Phil. Trans. 1802, p. 285 5, or Journal, vol. IV, p. 150,
Vout XXXII, No, 153.—NovemBer, 1812, P The
o
210 PRIMITIVE CRYSTALS OF SOME CARBONATES.
ae iron~ _ The primitive angle of iron-spar is still more remote from
that of the carbonate of lime, which it exceeds by nearly two
degrees. I have examined various specimens of this substance,
some pure white, others brown, some transparent, others opake.
That which gives the most distinct image by reflection is of a
brownish hue, with the semitransparency of horn, It was
obtained from a tin mine, called Maudlin Mine, near ‘ Lost-
withiel, in Cornwall, ' By repeated measurement of small frag-
ments of this specimen, the aagle appears tobe so nearly 107°,
that I cannot form any judgment whether in perfect crystals it
will prove to be greater or less than that angle.
In this instance the carbonate of iron is nearly pure, and so
perfectly free from carbonate of lime, as to render it highly
probable, that in other specimens, having the same angle, but
containing also carbonate of lime, or other ingredients inter-
mixed, the form is really dependent on the carbonate of iron
alone.
Mies een. , it appears, however, not unlikely, that when substances,
bably most. Which agree so nearly in their primitive angle, are intermixed
ees in certain proportions, they may each exert their power; and
", may occasion that confused appearance of crystallization with
curved surfaces, known by the name of pearl-spar. I cannot
say that I have made any accurate comparative analyses, which
may be adduced in support of the hypothesis, that mixtures
are more subject to curvature than pure chemical compounds ;
but it is very evident, from the numerous analyses that have
been made of iron-spar by other chemists, how extremely
variable they are in their composition, and consequently how.
probable it is, that the greater part of them are to be regarded,
as mixtures ; although it be also possible, that there may exist
a triple carbonate of lime and iron asa strict chemical com-
pound, ~
Perhaps some It seems not unlikely, that there may hereafter be found
carbonate,mo- some carbonate allied to the preceding, which may owe its
dified by man. : .
ganese, one form to the presence of manganese ; but notwithstanding the
liberality which happily prevails in general among those who:
have it in their power to assist in such inquiries, I have not:
had the good fortune to meet with any such compound; and,
Tam unwilling, merely in the hope of making such an addi-
* ton,
ECONOMICAL LAMP: 911
tion, any longer to defer communicating an observation, which
I hope will be of reaj utility in the discrimination of bodies that
differ so essentially in their composition.
IX.
Account of an Economical Lamp for producing Heat, with a cons
siderable saving of Oil. Ina Letter from a Correspondent,
a.0.,C,
To Mr, Nicholson.
SIR,
Vf F you should not think the following experiments too tri- Introductiow.
Hi fling for insertion in your excellent Journal, it is probable, Eee and
that soch of your readers as are in the habit of using an Argand tenth of an Ar-
Jamp in their chemical researches may feel interested in them. aoe tee
They certainly have some claim to attention in an economical third of the
point of view :'and this, I think, no one will deny, when he ol:
is informed, that he may procure a lamp at one tenth of the
price of the cheapest Argand lamp; which will produce an
equal, if not a greater degree of heat ; and effect a saving of at
least one third of the quantity of-oil consumed.
Experiment 1.a. An Argand lamp, which is supplied by a alin At:
fountain, so that the oil can never become very hot, was made Sos ache
to burn as bright and strong as possible, without smoke; and Ras el
was found to consume 447 grs. of oil, in an hour. Two eg a000 ots. of
thousand grains of rain water were exposed to the heat of this water in 7 m.
lamp in a glass matrass ; they boiled in seven minutes,
_b. As Isuspected that the lamp did not produce its greatest Same lamp,
effect, on account of the wick having been in the oil for alength rae ae 1
of time, I caused a new one to be put to it, and every precau- consumed 500
tion was taken to make it burn as powerfully as possible. It ss A Leip
now consumed 500 gers. of oil in the hour, and made 2000 grs. water in 6 E
of water to boil in 65 m. min.
Exp. 2. I caused a small tin lamp to be made, with four Exp. 2. Alamp
burners ; and having a tube in the centre, to convey air to them; sacl wie
each of the burners containing eight threads of cotton, of the &c, egutanieriog
diameter of j. of an inch. This lamp, when burning as Oly 200 grs.
; i i of oil per hour,
strongly as possible without smoke, consumed in one hour and boiled the
200 grs. of oil, and made 2000 grs. of water boil in 10m. (See hore in ten
plate 5, fig. 3and 4 ; and the description at the end of this ~~
letter.)
P2 We
912
It saved more
than one third
of the oil.
Exp. 2. Ano-
ther lamp, but
with the same
cotton, in 8 se-
parate wicks,
consumed 300
grs. of oil per
hour, and boil-
ed the waterin
6% min.
Ifs effect was
therefore
equal to that
af the Ar-
gand lamp;
but one third
of the oil was
saved,
}
Exp. 4. smaller
wicks Consum-
ed more oil,
without in-
creasing the
eiect,
When the
chimney glass
was shortened,
the effect was
increased :
and the saving
nearly one
half.
ECONOMICAL LAMP.
We may here observe, that the Argand lamp expends, in
raising 2000 grs. of water to the boiling point, 52°! grs. of oil ;
and that the lamp just described requires only 33°3 grs. to pro-
duce the same effect, which is a saving of 18°8 grs. or more
than one third,
Exp. 3. Although the lamp described in the last experiment
did not produce an effect nearly equal to an Argand lamp, in a
given time ; yet I could clearly perceive that the principle upon
which it was constructed was good, and capable of being car-
ried to a much greater extent. I therefore ordered another to
be made, in every respect similar to the former ; except in the
number of burners, which were increased to eight, each of
which contained four threads ; so that the quantity of cotton
in the wick of each lamp was exactly the same. This lamp
consumed 300 grs. of oil in an hour, and made 2000 grs. of
water boilin 65 m. Its power, therefore, was equal to that of
an Argand lamp ; and if we take the quantity of oil consumed
by an Argand Jamp in heating to ebullition 2000 grs. of water
in 65 m. at 45 grs. (which is evidently too small a quantity)
and that consumed by this lainp, in producing the same effect,
at 30 grs. the quantity required by the two lamps to produce.
a given effect, in a given time, will bein the ratio of 2 to 3.
Exp. 4. a. The same lamp was used in this experiment, as
in the preceding ; but as four threads appeared to fill the tubes
too tight to admit the free ascent of the oil, only three were
put into each of them ; and a glass, 14, in. in height, and 2 in.
in diameter, was placed over the fame, asinan Argand lamp.
When thus adjusted it consumed 320 grs. of oil in an hour;
and caused 2000 grs. of water to boil in 64 m.
b. As the effect appeared to be somewhat diminished by the
elevation of the matrass to too great a distance from the flame
of thelamp, this glass was removed, and another, only 1 in.
in height, substituted in its stead. The flame did not appear to
be as vehement now as before: it nevertheless produced a
greater effect, which was owing, no doubt, to the bottom of the
matrass being nearly in contact with it. Only 276 grs. of oil
were consumed in the hour ; and 2000 ers, of water boiled
strongly in Of m. ‘
This appears to be the preferable mode of using the lamp, as
it thus produces a greater degree of heat than an Argand lamp,
eyen-
ECONOMICAL LAMP. 913
even under the most favourable circumstances ; and consumes,
in the same time, 224 grs. less of oil, which is a saving of about
5, or nearly half. If we calculate the quantity required by
each to produce the same effect, it will be still more in favour
of mine.
Exp. 5. a. As the advantages arising from bringing the sub- Ep ane cf
stance to be heated, as near as possible to the flame of the lamp, pana’s lamp is
appeared to be so considerable, it was natural to conclude, that less when the
oy r i glassis taken
similar effects would attend the shortening of the glass of the away.
Argand lamp, or the removing it altogether. Accordingly,
2000 grs. of water were exposed to the heat of this lamp,
when burning as clear as possible, without a glass. ©The water
did not boil in less than 7$ min, This, therefore, did not ap-
pear to be any improvement, ‘
b. Tadded to the Argand lamp a glass 2 in. in diameter, and But a short
12 in. in height, from the base of the flame. Its power was Peels
considerably increased, for it made 2C00 grs. of water boil in fifth of the oil
G1 m. and consumed only 400 grs. of oil per hour. an the-Aclanee
Those who do not think it worth their while to procure a
lamp similar to that which I have recommended, will at least
find it a considerable improvement, to reduce the glasses of
their Argand lamps, to the dimensions here specified, which will
cause a saving of one fifth of the quantity of oil at present
consumed.
_Exp. 6. One of my principal objects, in the construction of Exp. 6. The
this lamp, was, that I might be able always to procure an equal re cone
degree of heat ; and one that could be augmented or diminished steady, and is
uniformly. The following experiments were instituted with a eaten
view to determine, whether it possessed these properties or not. of burners,
I have arranged them into a table ;
m. m.
8 | 3%
714 4
6 | 42hardly | 42
5 | 6 nearly |} 5:6
4 | 6 7
3 | 93 Os
2/15 14
1 {i 30 28
the first column of which indicates the number of burners em-
ployed; the second, the time required to raise 1000 grs. of
Ve rain
914 ECONOMICAL LAMP,
rain water to the boiling point ; and the third, the time required
by calculation to produce the same effect ; taking the first expe-
riment for the standard, viz. that with eight burners, the lamp
will make 1000 grs. of water boil in 3£m., which is very nearly
half the time which it requires to make 2000 grs. boil.
The. real times are copied exactly from the memoranda I
made while performing the experiments; and I was much sur-
prised to find how nearly they coincided with the times by cal-
culation : especially since the watch used had no seconds hand,
In the last experiment but one the water never boiled strongly ;
and in the last it only just simmered. I have added a sketch
and description of the lamp, for the use of those who may
wish to procure one like it. Its dimensions are exactly double
er those of the drawing ; with the assistance of which any tin-
ee ig man will be able to make it ; and I should recommend it to be
without aug- made with a reservoir, to prevent the oil from being much heated,
menting t e ef-
ing the ef- 46-1 have found by experiment, that this circumstance consi- |
fect. Hencea : :
reservoir is ad- derably increases the quantity of oil consumed in a given time,
viable, without adding, in the least degree, to the heat of the lamp.
The price of one, similar to the drawing, will not’exceed 1s. 6d.
exclusive of the glass, which is about one tenth of the price of
the commonest Argand lamp that I have seen.
lam, Sir,
Your constant Reader,
L.O. C,
Description pl. V, fig. 3,4. A the body of thelamp; B. B.
the burners ; C. tube for conveying air tothe flame; D.D.D.
small feet which raise the body of the lamp, and allow the free
access of air to the tube C. ; E. E. bended wires, which support
the glass F. ; G, small tube for filling or emptying the lamp*.
* Tt would afford an acceptable result, if the writer would also mea-
sure the light afforded by the lamps under comparison, as well as the
heat, As the method of shadows, though very simple and easy, is cer-
tainly not in general use, I would here repeat, that when the shadows
of the same object, projected upon a wall or surface by two lights, are
equally dark, the lights themselves are equally intense—that, if not, the
darkest shadow will be projected by the interception of the huinlivest of
the lights ; and that, if this brightest light be then removed farther from
the wail, till both shadows become equally dark, and the distances of
the lights from the wall be i in that situation measured, the intesjsity of
each
NEW ARRANGEMENT OF KEYS OF MUSICAL INSTRUMENTS, 2)
Or
X,
Description of a new Construction and Arrangement of the Keys
of Musical Instruments, invented ly Joun Trotter, Esq.
“(W.N,)
General ac-
N the piano forte and other instruments, in which the notes bo
of the musical or diatonic scale are afforded by wires, strings,
pipes, or other parts of invariable figures, lengths, or other
affections, and produced by the action of keys,-it is well known,
that one principal series has its notes designated by the first
seven letters of the alphabet, A, B, C, D, E, F, and G; and .
that ihe intervals of gravity or acuteness are all (nearly) equal
to each other, except the interval between B and C, and that
between HE and F, which are (nearly) half the magnitude of
the others ; and that by interposing other notes at (nearly) equal
distance between each of the greater intervals, a series of such
smaller intervals (called the intervals of semitones) is constitu-
ted, and affords the number of twelve notes in a!l ; out of which
itis practicable, by commencing from any individual note, to take
a regular diatonic series, having its notes and half notes disposed
in a similar manner to those of the principal series before men-
tioned. ‘The present occasion does not require any illustration
of the nature of the musical scale, or the degrees of imper-
fection to which the secondary scales of fixed instruments are
unavoidably subject, and the remedy usually afforded in part by The principal
temperament. Practical musicians are aware, that the white keys *¢7705) Or BU"
of a piano forte, and the lines and spaces of a music book, are pressed by sim-
apptopriated to the notes of the principal series, called the natu- a reat
ral scale ; and that the auxiliary half notes are given by black by white keys.
keys on the instrument, and marked in the book by the same
character as denotes the note next ascending or descending, but
have the modifying character of flat or sharp pretixed in the cliff Notation by
or elsewhere. hat this mode of notation is unscientific and flatsand sharps
. condemned.
awkward ; and that the correspondent structure of the keys is
irregular and embarrassing, will scarcely be controverted by any
one who shall maturely consider the subject. Inthe natural
each will be in proportion to the square of its distance. For example;
if two lights give shadows equally black or dark, when their distances
from the wall or surface are respectively five and seven feet, the inten-
sity, or quantity of light emitted from them, will be respectively as 25
(or 5%5) and 49 (or 747).—N. ;
Series
216 , NEW ARRANGEMENT OF KEYS OF MUSICAL INSTRUMENTS.
series, every character simply indicates its note; but if we take
the fundamental note one tone higher, viz. from C to D, then
two sharps, namely f and c, will be marked in the cliff; and the
same characters, in effect, will no longer indicate the same notes,
or require the same keys tobe touched. If we assume the funda-
mental two tones above C, four sharps will be marked in the
cliff, &c. And it is accordingly found, that in transposing and
! performing on the different keys. the fingering is very different
Mr. Trotter ineach. Mr. Trotter has found a simple and effectual remedy
ee al ha for this last difficulty, by constructing the keys in such a man-
key in regular ner that no preference as to white keys is given to any particu-
ett he pickin lar series ; but every series is fingered precisely in the same
semitones; manner. He places the white and black keys alternately in
ee succession for every one of the twelve semitones ; and the con-
invariable sequent rule is, that for the sharp series ascending from any note
a whatever, the key note itself is to be touched, and then the
every key of two keys next ascending of the same colour, and these are to
music, be followed by the four keys next ascending of the opposite
colour. Thus in fig. 5, pl. V, the key of the Note C being
black is to be foliowed by the black keys of D and E, and.
afterwards by the four white keys of ', G, A, and B. And it
is easy to show, that in the flat series a rule no less simple and
universal prevails throughout, viz. that the key note, and the
next above, and two next below it, are to be of the same calatig
and the other three of the opposite colour,
Ulustration by In the same figure, where W, W, &c. represent the white
the engraving. keys, and N, N, &c. the black keys as usual, the letters”, 2, °
i; represent the same black keys continued, and a little depressed.
below the white ones.’ By this means the performer has bis
election to touch either N orn of any key at pleasure ; and
as the nature of the passage may require. This construction is
shown in profile at fig. 6.
renter ene’ I was present when a professional gentleman, who had prac-
on the instru- tised on this improved instrument two days, performed several
Lay by 4 PTO- Dieces of music upon it, which were of difficult and rapid exe-
essional man.
| caution. He spoke with much approbation of the facility and
advantages it affords, and particularly remarked, that the im-
provement 7, 2, &c. allows certain passages to be performed
in a superior m apes sla if: aneeiee by means of the faces
N. N,
PENDULUM OF COMPENSATION. 917
N.N. &c. would be much less manageable. Not being my-
self a performer on any keyed instrument, I can only express
my approbation in general terms. . Letters patent have been
granted for the invention.
XI,
A new Compensation Pendulum, without Joints or Surfaces
bearing against, or moving upon each other. Ina Letter from
a Correspondent. (R. B.)
‘To Mr. Nicholson.
_ SIR,
MINCE the invention of pendulums of compensation for pendutums of
changes of temperature, there nave been a number of compensation.
| excellent contrivances, by means of the contrary expansions of
metallic bodies, for keeping the centres of oscillation and
suspension at an invariable distance from each other. In the Mercurial,
quicksilver pendulums, or any of the contrivances which re-
quire the use of a fluid, it may reasonably be supposed, that
the changes, which are to compensate each oiher, do take
place at the same time as the temperature becumes altered ; and
that the quantity and effect of the compensation continue the
same for any length of time, during the existence of the
machinery. But in pendulums composed altogether of solid
materials, both these results have been called in question. In Gridiron pen-
the gridiron pendulum, it has been insisted, that the adjustment ene) object-
of the expansions is by the construction of holes and pins, not
capable of extreme exactness ; and that the variation, to which
the pressure of contact may be liable, and the stickage of the
bars, (which rub against the frame) may be more than sufficient
_ to counteract and give uncertainty to all smail variations,
required to be compensated. And in all constructions of bars peers ee
of steel and brass, soldered or connected lengthwise, it has Beales baci
been doubted—not only whether the wire-drawing and upseft- ea action
_ ing of the elastic metalsthemselves, under a state of such severe aimee
_ force, may not allow for all small changes, without perceptible
_ flexure,—but likewise whether the flexure, which in larger
_ changes is perceived, may not become altered, after a course of
_ time, and long exposure to the effects of heat and cold.
ig Perhaps, Mr. Nicholson, you, or your readers, may be inclined
VF to
218 PENDULUM. OF COMPENSATION.
to think these speculations the mere creatures of theory; and
may, from the actual performance of many surprising time-
measurers, be disposed to conclude, that they may be practically
se of noconsegquence. But I would urge, Sir, that it is by this
changesin kindof minute and scrupulous investigation, that discoveries
bodies useful. eome to be made ; and that, while the best makers hold different
Opinions, and with all their skill (which I traly honcur) cannot
foretel, beyond a certain point, whether the work they are
upon will answer their expectation or not,—we may actually
expect still to make discoveries_in this useful and curious pur-
suit. And while we make our experiments and operations
under the guidance of some probable hypothesis, or doubt, or
~ indication, the objects we produce may, in many instances,
be found to possess unforeseen advantages, or serve to establish
new truths, perhaps not suspected by the operator himself.
r
New pendus I have been desirous of constructing a pendulum, composed *
of expansion bars, not subject to the violence of soldered or
adherent faces pulling against each other, or the uncertainty
of contacts, the rub of surfaces, the stickage of joints, or the
earing parts of levers, The following has been going for
several years.
Construction, In the annexed drawing, (Fig..2, plate v.) f g and i h repre-
nay sent bars of brass, respectively united by rivetting and
each of brass Soldering with two bars of steel at the ends where they touch,
without, and but their faces do nat touch except near the ends, as shown in
steel within :
are rivetted’ the drawing. :
together, and =§ At the extremity g 1ni of the system, all the four bars are
eee connected, as is alsoshown in the cross section p ; but at the
one end only. other extremity the bars fk are connected, and so likewise are
pi Soa kG the bars m h ; but there is no union between k andm. At 0,0,
thin parts, &c, the bars are filed away or notched, so as to leave each of them
thin on the side farthest from the middle line of the system.
ad shows part of the pendulum rod, of which a fs the point
of suspension, connected by a spring with b, a clamp adjust-
able by sliding along the face of fg, and fixable in any required
position by the screw. And d is part of the lower rod, broken
off to save room in the plate instead of being continued down
to the ball.
Particular de- ‘The effect of thiscombination may be thus explained : When
penton rae by an increase of temperature the brass bars f g and ih become
p longer
PENDULUM OF COMPENSATION. 219
Jonger than their correspondent steel bars k] and mn, the effect upon
; ‘ : change of tem~
_ whole of the flexure will take place without any strain or perature.
tension of any practical importance, in the thin parts ato, o,
and the faces k m will be brought nearer together, and so like-
wise willa andd; by which means the pendulum rod will be
shortened, and this shortening may, by the due adjustment of the
clamps, be made precisely to compensate for the lengthening of
the rod, caused by its direct expansion by the same increase of
temperature.
I believe the happy expedient of confining the flexure to a Hardy’s
thin part of the bar was first used by Mr. Hardy, in his expan- balance,
sion balance.
In order to show the quantity of effect, let fg, kl (Fig. 2*) Principles of
represent one pair of the bars, of which o g, ¢/ are the thin parts, Fay ag ae en
and c o the depth of the notch ; and suppose o¢ to be the effect tity of effect,
of the expansion by one degree of heat in the thin brass part
beyond that of the steel bar; which will be 0':00000331 in
unity.
Or, gobeing equal to eo, the quantity eo will be=
000000331 x depthof notch,
But the whole excess of expansion will be greater in propor-
tion as the whole bar is longer than c o, or the depth of notch,
that is, 0°00000331x length of bar = whole excess of
expansion.
And as this excess will cause an angular deviation in the line
¢otoce and beyond, and will also cause a similar deviation in
gf, the linear deviation of the extremity fwill be greater than
that of o, in proportion as the whole bar is longer than co, or
the depth of notch; that is, depth of notch : length of bar ::
excess of expansion = 000000331 x length of bar: linear
ae length of bar? x 0°00000831.
deviation of f= ——______—_—_———-
depth of notch.
In order to adjust the compensation, the effective length of
the bar is variable by means of the clamps, and the deviation of
the parts of the pendulum rod, above and below the set of bars
from a precise right line, would not exceed ten minutes, if the
parts were inflexible, and the bars very short ; but the spring of
suspension is practically sufficient to preserve the right line.
Production of
fire by com-
pression,
The piston
generally too
long.
Half an iach,
IGNITION FROM COMPRESSED AIR.
XII.
Abstract of an Essay on the Construction and Effects of the
Pneumatic Tinderbox, ly Le Bouvier Desmortiers*.
HE inflammation of spunk in the pneumatic tinderbox, by
the compression of air alone, isa phenomenon, with which
chance, the father of discovery, has lately enriched natural philo-’
sophy. Many have reasonedon its cause ; which some consider
to be caloric, others electricity ; but no one, that I know of,
has attempted to support his opinion by experiments+. Without’
bias for any hypothesis, I have made some researches on the
construction and effects of the pneumatic tinderbox, the results
of which shall be the subject of the present paper. In the-
first part, I shall consider what relates to the structure of the
instrument; in the second, I shall give an account of the experi-
ments, that tend to the discovery of the cause of its effects.
I. The fixst construction of these tinderboxes was a little
faulty in the piston being commonly eighteen or twenty lines
long. This was said to be necessary, that the air might not
escape, when the piston was in action ; for, if there were any
point not ‘accurately fitted to the inside of the tube, the air
escapes, and the spunk does not kindle.
The goodness of the instrument does not depend on the
with atube of lengthof the piston, but on the accuracy with which it fills the
six inches,
sufficient.
bore of the tube ; with a tube well bored and a piston of six
lines, the air will no more pass than with a piston of twenty.
Accordingly, for a tube of six inches I have reduced the piston —
to six lines, which adds an inch to the column of air, and
diminishes the friction two thirds, so that the effect of the
tinderbox is more certain, and it is more easily used. Witha
little dexterity you may kindle the spunk by holding the tube ia ~
one hand and pushing the piston with the other, without being
obliged to rest itona table, or any other solid body. Mr.
Dumotiez, a skilful maker of philosophical instruments, is so
fully convinced of the advantage of short pistons, that he now
makes them of these dimensions. |
* Journal de Physique, Vol. LXVII, p. 125.
+See Journal, Vol. XX, p. 278; and Vol, XXI, p.234,
They
' circle, the peirphery of which touches the interior edge of the
IGNITION FROM COMPRESSED AIR. 991
They should be employed also in the syringes of air guns*, Short pistons
of fountains acting by compressed air, of the apparatus for Of advantage
ad 4 i 5 in other
aftificial mineral waters, of fire-engines, which are worked machines,
with so much labour, and even of air-pumps. As the shorten-
ing the piston is an advantage to the pump, we obtain a greater
effect with less labour, and in a shorter time, than with long
pistons.
It is essential too, that the instrument does not leak at the The chamber
part where the spunk is placed, because there the transient must be air-
action of inflammation takes place, anda slight emission of air peer ate Ee
would prevent the effect. But this effect is produced, though the piston te
the piston does suffer the air in the tube to pass it. To satisfy “°°
myself of this, I made the following experiment, at which they
who have seen it were greatly surprised.
In the length of the piston I made a groove a quarter of a pour erooves
line broad. The spunk took fire as before. Three other made in the
grooves were added successively opposite one another, so as to eas ie
divide the piston into four equal parts ; and still the spunk took effect,
fire+. When the grooved piston is moved backwards and
forwards in the tube, the air may be heard entering or issuing
out; and the friction is so slight, that the effect of the instru-
ment is easily obtained by pushing it with the hand. This kind
of piston would be preferable to those that fit accurately, if a
solid substance were employed, hard enough to resist the con-
tinual friction of the air passing through the grooves, if E
may be allowed the expression. The grooves in leather pistons
soon alter their shape, and spread so as to allow the air to pass
in too Jarge quantity.
The piston with four grooves acting very well, I made one but one of
with a single groove, of dimensions equal to the other four, and Cea
what I foresaw actually took place : there was no inflammation.
_ The following are the reasons of this difference.
The extremity of the grooved piston exhibits the area of a Why the small
grooves do not
: i prevent the
grooves. Thecolumn of air contained in the tube rests almost action,
wholly on this base. There are only the parts corresponding to
* In the air-guns of Germany, which are the best we know, the
piston of the syringe is extremely short,
_. # I tried this experiment with Mr, Bancks, at his house in the Strand,
and we found it succeed completely with a common cond ensing syringe of
Ris making.—C,
the
1
19
i)
and the large
one does.
Choice of the
touchwood,
Danger of
blowing on it,
IGNITION FROM COMPRESSED AIR.
the grooves, that are continued through the length of the pis-
ton, and communicate with the external air. When the piston
is pushed with sufficient velocity to kindle the spunk, the parts
of the column corresponding to the grooves rush into them
with equal velocity ; but the friction they experience in passing
through such narrow tubes occasions a resistance to their pas-
sage,a kind of choaking, that suffers only a part to escape,
while the column resting on the area of the piston is pushed
entirely toward the extremity of the tube, where the spunk to
be kindled lies.
Iu the piston with a single broad groove, the area of the cir-
cle, on which the column of air rests, is much smaller, conse
guently the column itself is less. ‘The resistance the air expe-
riences in passing through the groove is next to nothing; for
we hear no noise on moving the piston backward and forward ;
and as air expands in all directions, when the piston is moved,
the column resting on the area of the circle, resting at the same
time laterally on that which answers to the groove, it recedes
from all the points of contact, and flows entirely through the
channel it finds open. It is so true, that it wholly flows
out, that the piston, when it touches the extremity of the tube,
remains there ; while with other pistons a sufficient quantity
of air is retained to occasion a spring and repel them.
I think it proper to say a word or two on the quality of the
spunk. The driest, softest, and least impregnated with nitre,
should be chosen. In that of the best quality a piece will not
always be found equally good throughout. Some contains a
great deal of nitre, and is kindled with more difficulty*. This
may be known by the cool taste it leaves on the tongue; or by
kindling it: for when it has taken fire the nitre melts, and
sometimes throws out sparks, that may be dangerous when
they spirt out of the instrument, particularly if made with a
cock. As it is usual to blow on the spunk, to try whether it
be kindled, a spark may be thrown from it into the eye. This
painful accident once happened t@me.
* Spunkis prepared from agaric, which is first boiled in water ; beaten
well when dry ; steeped in astrong solution of saltpetre; and lastly dried
in an oven. If the solution of nitre be too strong, theagaric is loaded with .
this salt, which retards its inflammation,
5 They
TGNITION FROM COMPRESSED AIR. 993
coal
~ "They who imagine, that electricity kindles the spunk; consider Electricity
these sparks as an incontrovertible proof of their opinion. I supposed to be
think they are mistaken in this case; yet I must not conceal a oe alee of
fact communicated to me by Mr. Veau-Delaunay, which seems ;
to confirm this opinion, of which he is a partisan. Out of
twelve times, when he operated with the instrument without
any spunk in it, he saw sparks emitted three times. There are
strong reasons, however, for suspecting, that electricity is not
the cause of the inflammation here. These I shall give in the
second part of this paper, concluding the present with an im-
portant observation on the construction of pistons.
If we could find an elastic substance sufficiently compact to On the con-
_ be turned in a lathe, we should have perfect pistons, that struction of
would spring and adapt themselves to the inequalities of the see bi
tube, without suffering a bubble of air to escape. I have made Attempt to use
some with caoutchouc, softened before the fire, in order to give elastic gum for
_ ita degree of elasticity more obedient to the inequalities of the ibe
tube. But on attempting to turn it in a lathe, it bent under
_ thetool. Even the edge of a razor would not take hold of
" it; so that the piston remained uneven and almost ragged, and
' yielded like soft wax under the fingers. In this imperfect state
_ itso far prevents the air from escaping, that a column of three
’ inches is sufficient to kindle the spunk ; bat after a few strokes
_ of the piston the heat dilates it to such a degree, that it cannot
‘ ‘be moved without considerable force, If a drop of oil be put
Ly on it, it moves easily ; but this soon spoils the instrument ; for :
the oil dissolves the caoutchouc, and forms a varnish, which, as
_ the piston grows hot, makes it adhere still more strongly to. the
' sides of the tube.
_. Might not these inconveniences be avoided, by arming the This might be
piston rod with caoutchouc, and covering this with leather ? di with
pat this process succeeded, it might be applied with advantage to
‘ all sorts of pumps:
0 II. To attain, if possible, a knowledge of the principle of What is the
inflammation in the pneumatic tinderbox, four things are to be gma de ‘
‘considered—the materials of the tube, the matter contained ‘in
{ he tube, the materials of the piston, and the friction. Among
the materials of the piston I include the grease, with which it
is coated, to make it move more casily, and render it fitter to
ther.
In
994
Ts it elec
tricity ?
Arguments
against this,
Yn 2 metallic
condenser we
cannot see
what takes
place.
We can in a
glass tube.
(Glass flutes.)
IGNITION FROM COMPRESSED AIR.
In examining the question whether the spunk be kindled by
electricity, I consider
Ist, That no part of the instrament is insulated; and that
insulation is a necessary condition for producing sensible elec-
tricity with any of the machines we know. I say machines
that we know, because the animal electricity, that manifests
itself without insulation, is an exception to our mechanical
means, and cannot here be taken into consideration,
2dly, The friction of the piston, which is a greasy body,
against a metallic substance, is not calculated to produce elec-
tricity.
3dly, Experience demonstrates, that, unless during storms,
the atmosphere seldom exhibits any signs of electricity at the
height in which we breathe it; and that we must search for
them with instruments in a more elevated region, or when elec-
tric clouds are passing over our heads. How then shall we
estimate the infinitely small quantity of electric matter ina
cubic inch of air, or even less, which the instrament contains.
Fourthly, It is not without great difficulty, that we can
kindle spunk with strong electric sparks. I have discharged a
large jar on spunk strewed with powdered resin, andit has re=
mained unkindled, though the resin caught fire, and burned en-
tirely away. :
As long as the instrument was made with metallic substances
only, we were obliged to confine ourselves to the exterior marks
of inflammation alone, without being able to assign the true
catise, or at least farnish proofs of it. For to guess is not suf=
ficient in natural philosophy ; we must demonstrate, in order to
give to facts that degree of certainty, which befits science ; and
this we cannot do here, without seeing what passes at the very
point of inflammation.
The means are very simple. Nothing is necessary, but to
substitute a glass for a metal tube. Those found in the shops
being too slight, I applied to Mr. Laurent, the inventor of glass
flutes, requesting him to procure me tubes of a similar quality.
‘This artist, as much distinguished by his civility as by his ta-
jents, furnished me with three, which I fitted up, The first, —
eight inches long by eight lines in diameter, did not kindle the —
spunk. ‘Thesecond, nine inches long’ by six lines and three
quarters in diameter, kindied it completely. This being’ de-
stroyed
IGNITION FROM COMPRESSED AIR. 225
stroyed by accident, I tried the third, eight inches long by seven
ines in diameter, which succeeded equaily well.
When the instrument is made to act, and the spunk kindles, Appearances.
we see a bright flash, that fills the capacity of the tube; and fhe oom
this light is so much the more vivid, in proportion as the com- sion be rapid :
pression is more rapid. If the compression be less powerful,
the spunk does not kindle, but we perceive in the upper part of
the tube a light vapour, that falls in undulations on the pision.
When this has disappeared, if we draw back the piston, the va- , light va-
pour will reappear, as Jong as there is any air in the tube. pour, if not.
These effects may be produced several times in succession,
merely by pushing the piston with the hand. This vapour is
~so thin and diaphanous, that it is not perceptible in a strong
light. It requires a sort of twilight to see it well.
But whence arises this vapour, and what is its nature? As- Whence arises
suredly it isnot furnished by the materials of the instrument ; , this vapour ?
it can only proceed, therefore, from what it contains, from the
atmospheric air, Now, according to the present state of our
knowledge, the air contains only nitrogen, oxigen, and a very
small portion of carbonic acid ; all gasiform substances, which
are kept in this state by the great quantity of caloric that pe-
netrates them, and are consequently heavier than it*. But in
compressing the air contained in the tube, what is the substance
that must first give way ? Is it not that which is lightest, the Isit the matter
caloric, that general solvent, that principle of fluidity and vola- es eras
‘tilization, which gives wings even to metals to raise themselves
in the air? Is then the vapour in question caloric, rendered
visible by the approximation of its particles, which are com-
pressed by the surrounding air, as air becomes visible in passing
through liquids ? This idea, which I am far from presenting
* The air likewise, in its ordinary state, contains twelve grains of ft is not aque-
. water in a cubic foot. This small quantity of water, reduced to the ous vapour.
_ Proportion of the quantity of air contained in the apparatus, contri-
butes.nothing to its effect : for the heat produced by the friction could at
most reduce it to vapeur, and in this state it would not kindle the spunk,
If the vapour seenin the tube were water in a state of expansion, when
“it fell onthe surface of the piston it would condense there, and appear
in the state of aliquid. But the surface of the piston always remains
.dry, though on moving it the vapour appears and disappears several
times.
Vou. XXXII, No. 153.—-NovempBer, 1812, Q asa
Trials. with
other gasses,
IGNITION FROM COMPRESSED AIR.
as a thing proved, acquires more probability from. the following
experiments*,
I substituted hidrogen for common air, and the yapour
showed itself as before ; but the spunk did not take fire. With
carbonic acid.gas, and with nitrogen the effects were the same.
The latter, which contained a little nitrous gas, gave .a some-
what denser vapour. ,Oxigen, lightly compressed, yielded ,a
_ Vapour more rare and transient than that from common air. It
The vapour
cannot arise
from the
grease employ-
ed,
It contains no
acid.
had scarcely fallen on,the piston, when it rebounded and dis-
appeared. When I compressed oxigen with a preper force for
producing inflammation, the spunk, which commonly takes. fire
only at the anterior part, was almost entirely burned: yet for
this experiment I used a copper instrument, the piston of
which lost airso much, that.it would no longer kindle spank
[with common air].
Perhaps it willbe said, that the vapour came from the greasy
matter on the piston, which adheres:to the sides of the tube ;
and that it is expanded by the heat produced by the friction.
To this I answer, in this case, 1st. The vapour should not show
itself before the greasy matter is deposited on the sides of the
tube ; yet.it appears at the first stroke of the piston, before the
tube becemes greasy. 2dly, It should show itself below the
piston, inthe part which the piston has left ; but, on the con-
trary, it always shows itself above, 3dly, There is no vapour,
when the piston-loses much air, if the friction be ever so rapid.
4ibly, The vapour should be more apparent, when the piston
exerts its friction throughout the whole Jength of the tnbe,
than when it is confined .to a small part of its upper extremity ;
yet the reverse frequgntly happens. Sthly, When the air is
entirely decomposed no mere vapour appears, but it shows
itself again, if ever so little fresh air be introduced.
As it was essential to ascertain whether the vapour did not
contain an acid principle, I fastened to the surface of the pistoa,
with a little green wax, a piece of muslin dipped in infusion of
litmus, and afterward dried. After twenty strokes of the pis-
ton the colour was not changed. I pat on a second piece of
muslin larger than the first, and the edges of which were loose.
* Mt. De Luc ascribes the ignition to the condensation of the matter
ef heat. See Journal, vol. XXI, p, 234.--C,
This
IGNITION ‘FROM COMPRESSED AIR. 027
This was butned-all round, without'the colour 6f the rest being
altered. »Lastly,a third piece, which was wet,’experiénced no
~change'of ‘colour.
From these experiments it follows, that no ‘acid ‘principle is General infe-
‘developed : ‘that all aeriform substances, as'well’ascomitien air, 2¢*s-
¢produce alight vapour : ‘that no other gs, “except ‘oxigen ‘and
“common air,'kindles the ‘spunk : that ‘oxigen prodieds a! nth
more ‘powerful combustion than ‘common “air, *¢onsequétitly
oxigemacts-an-important-part in the inflammation : ‘that-as itean
exert its action only when set ftée by the decomposition of the
common air, of which it constitutes a fourth}part, it follows,
that the air contained in the tube is‘decomposed by the simple
force of compression : that the vapour produced is not owing
to the oxigen, sifice it shows itself equally in gasses that contain
No oxigen : that this vapour is the effect of some agent 'com-
mon to all] gasses: and that we'may presume it is caloric ‘itself,
rendered visible by the sudden ‘approximation of its parts in a
small space,‘whére it risés to a temperature that is increased in
the oxigen so as to’kindle the spunk*,
I am equally induced to believe, since the air, and it is the 7 yminous me-
same with all gasses, is decomposed by rapid compression, that teors indepen-
eats Caen eh ok bao in the «beeps a dent of electri-
the luminous meteors frequently perceived in hurricanes are city, |
not always the effects of electricity. I have observed several
times, on these occasions, that Saussure’s atmospheric electro-
meter affords no signs of any. I will mention a particular in-
stance, as it occasioned me no less surprise than damage.
In the beginning of the year 1803, being at my country jn ‘high winds.
Seat, toward evening a violent wind arose, which continued in-
creasing for two hours to such a degree, as to blow down
about sixty trees of prodigious size and height in an ornamental
plantation. dt threw them one vpon another ina row, and
some of them were broken off. Those that were torn up by
‘the roots brought up the earth with them to the distance’ of
* It sometimes happens, that the spunk is turned black without Vapour of a
kindling. In this case, as well as when it is kindled, if we draw back different kind,
the piston in the tube, a dense vapour, that may be smelt, issues out,
which is not of the same nature as the forrner. That shows itself be-
fore the inflammation ; this always succeeds it. That is the principle of
the inflammation : this a product furnished by the combustion of
‘the ‘spunk, of Which it has the smell.
Q 2 fifteen
2298
ANALYSES OF MINERALS.
«fifteen feet. The clouds flew with extreme rapidity, and twice
Magnesite.
*Magnesian
“Jimestone.
Wavellite from
Barnstable,
and South
America,
I saw flashes of light from them. I raised my electrometer,
armed with its conductor two feet long, but the balls still con-
tinued in contact.
If. these researches afford nothing more than conjecture, they
will have at least the advantage of serving as a guide to more
enlightened observers, whose labours may extend our know-
ledge of a very obscure subject, to elucidate which is difficult.
XI.
Analyses of Minerals. By Martin Henry Krarrots,
Ph. D. &e.
(Concluded from vol. XXXII, p. 384.)
M AGNESITE from Styria*.
WAR OSIA, jc gen sid sta fai coreee 48
Carbonic agid "icp utc: suruds xeon
AViEER pad weet Seats th adage kako uahew as oe
100
Gurofian (so named by Karsten from the place where found).
Carbonated lime........ RAMBUS 705
magnesia........ «erase, eee
100
Wavellite from Barnstable, in Devonshire.
PATA IIG oo cialis evciorore ER ARI wi 71°5
OORNe MAE: AVOMN Aisialepy Bite sos cnietmiacs os
WAU Sito a ae orale a sapien nase, aisles WOME
100
Wavellite brought from Hualgayoe in South America, by
Humboldt.
AUTIGGS | hil sceie sis Se Sut alae Nae 68
Sle SP eae MA ae eae 4'°5
COR TOGEL GEFEN ieint's wvinialicouie tugs alee a :
Water oeeteevnree5nre eeeeee * a@ee*t*reee se 26 &
100
* For a paper on this stone by Messrs, Haberle and Bucholz, see
Journal, vol, XXXI, p, 269,
Siliceow
ANALYSES OF MINERALS. 220
‘Siliceous guhr from the Isle of France. * Siliceous guhr.
BE acer tale cael ance bads dieu ge
PUNE S 2 o's aie e'e clei dic Bottle telarean
Oxide of- irons v:iasackarksssee. 25
MEE ae eet gy amt waieid aad ead
98
A green Eithaecl, having the i spcnecaeeaty of a sandstone, from Green sand-
Spessart. atc ie
PUR ctllecatheeWs Jk’ cite Sea feowe
MeV TS: RSS BE te)
ride OF MeN VER a ee oe
PVMARCES oso ety Vinils'uleic e's She shetwiarwe > Dy
98°25
Hepatite from Andrarum. Hepatite-
Sulphated HarylGs. oc «wets <eelde seca gO
| TESS Sr le PR an
Oxieilated iron... cede cece 8
PRIPEADING 5! 5) o¥iasias niehspeyeusiaiess 1a eae ote iwenkiek ok
REDALCOAN 2, > 33.0.0 o chuysin nein ehicaiO
Loss, including water and sulphur... 2°25
100
Router. =. ss Grapestone.
Renee tts, wise ens d cxmnaiee akin ee mae
a ha of wal Rio cis (ala inde’ Wgaredes deny GOITER
PBEICOICKACIG ss clew cls c owed sce « en haS
POwidevof iron. . 65. coe SIV HAST
DUN PEGI Ios igo enase reserere sere rwtarointe in inereteres* OD na
(ieee
96'5
* In the J. de Phis. 25" 8. ‘This being evidently wrong, the fi-
gures probably had fallen out and been replaced erroneously. by the
pressmen; and, as the loss is noticed, the whole sum should of course
be 100. From the appearance of the figures too, there being a vacaney
for one, I have little hesitation in correcting it as above.—C.
$ See Journ, vol, XXVIJ, p. 273, for a description of it—C
Lupe : Zircon
230., ANALYSES, OF MINERALS,
Jargon. __ Zircon from the Circars, inthe East Indies, Sp. grav, 4s55
Zircopian earth, ....ccew pseocrscs, OAs
STIG. mt rahtcrosy orcreree eae 300s oe = OD
OSTGOF dro Sie ko ho ie aa ieee
8°5
ee Spd _Red garnet from Greenland. .
-land. DUR ope seca Hae eee nite xb iaiielalie bin ign oa
PAIGE oo sion tien sr stegelerniensif lta sunny eae
WaBneala, . ms )eieie a oie Bish incites) ein eet
. ye) SRE ee ae Si ehieh imi ‘veese’ Lip
Oxide oftiran oC. aes ae etek ewe eee
—- MANQaNese, . verssseraves DSO)
Kannelstein. Kannelstein*. 98 75
SOBEL Ss vic, noaine enna hs Winkel on er
Binney |: .'s.siele cpr iiaieaaisels orale ocean
Ce Rane SPORE EN FS om Dee
Oxibvor tant 72, pul ok von 3 cc
Letere. oie ieeee dine oe eta 2°25.
, 100°
Soke Common schoer] from Eibenstock.
aig. SHER, tide vu osname cried ae
Binet: ch Ae ena teat rkerg att 34°50
WEABTIERIA, a1: oie'wieols: sic a eelelena!n RES
Oxidulated iron.............. kOe
Potash ceeece oe Een eh ence ne tena e ya ern ne eet 6
Oxide of manganese, a trace
Opake black Common schoerl from Spessart.
tourmalin of . Pha 6:50”
Haiiy. SileX.. Le cee ee ee cece secre ees cee, SOISO”
PN ORADIR Coa iso) e's n\n gota says n) ¢ wmola, ale eee
Mie he cine sin; valve p tipo asin ie 1:25
Oxidulated iron. ...o ieee ne renee 1 Zoe
| Patent, ay) coro ee: 5°50"
Oxide of manganese, a trace
97°75
* This appears very different from the kannelstein analysed by Lam-
padius, See Journ. vol, KX, p. 231,—C.
Common
ANALYSES: OF MINERALS, -
Common hornblende from Nora: .
BRT s 2a sx’, '.», o.0/'s nye, ue, oem eR
PPEAITIECS . oy'n"n°s te’ si elutatotik chetaletatateteh LE
PODS Pos a tetas eters ty tetetetatata etotetattatetea La
DREEPRICRI A, st) siahaet sola atte hal atas a Oe
Oxidulated-iron: so. 660465203 os 0°38
Manganese, ....... ote fate te hit ee a Rn ae
Water... ..% ater soeeetereos Cpe
Potash, a trace
coe
98 25
Basaltic horneblende from the country of Fulda, found in
volcanic basaltic substances.
BUGRG eee ies eeracccnns AF
SERMOOS S$ 5 shat bat seek ecace DO
BNE iia 'a tata ata ata tabetetah ate? sata tatatetele® HEM
DeAPMCwM ess sbi ko se NA Eee Se
Qxidulated iron, . ervee@orzeecevees oe 15
; ee Mee eh eka eee Seiet eee. O's
O85
Common black augite from Rhorgebirge, in Franconia.
Biles co ets ss dap riegeg cave
PONOTEE 5. hci hlovinviese dace sex lt
DAA INES Cs a loec: ss en noisier heals 1275:
MOIR DIRS a a oi cratlares et ptarehe’anni@rerntares ) yA
Oxide-of: iron, 1.44.4 «sae: age
has" MANSANESE .. secre ee O'2D
PV ARETE? . 6 nian Wisld > Ma dielanln O28
Potash, @ trace
97°75
Common green augite.
SHE cc sce c cere erencnnr es) OS
VEAP NCBI « oe'ss ole wie oe seen cde RBM
| ee aes oo Wdls co eae
PUUMNes . sees nade got a bas oases Te
Cmide-of- iron, 255 Aes ae les OEE
=-—— manganese, a trace
WE ecccccrcencde eda staves yb
231
Lamellar am-
phibole of
Haiiy.
Supercom-
pounded crys-
talized amphi-
bole of Haiiy.
Black augite
from Francge
nia,
Virescite of
Delametherie.
232
Black augité
from Frascati.
Pyroxine of
Haiiy.
Black garnet.
Gadolinite.
Fettstien.
ANALYSIS OF MINERALS: *
Black crystallized augite from Frascati*.
Melanitet+.
BU Ow FoF sieges Pape va Sate ek’ a
Lime). nila tach be [ns al ets
MagesBia'. Lhe aiinecasteasem aw ose say) x Sage
Alumine....... Teeter ee
Oxide of iron....... Seater tae
PAD EANESC eis u's\s seis 6's 1
‘Potash, a@ trace
93°75
SHORE oh, alsinin deer aie kee a meee a meee
gE phe: pe pie Ta ai a ea oo Oe
AMINE: 5.0(Uikia he bao he ome ee 9
Black oxide of iron.......... 2. 242a
Oxide of manganese .......... 0°40
101°65
Gadolinite from Bornkolm.
Eleolitet.
Witter Se tiaubaeaees «as . 60
Silex: fy... eye Yaak eit ee Scr aoe
Oxidulated iron .......2-eeeees 16°5
Watertacs owiss «.« doadceitays 28 ens jeyane aes
Oxide of manganese, a trace
99
Silex. Heals sheteisintehane cle fae) LAO SO
Altes cic is)2 cis he sae oka be
TD AMCE Ee iene wtnihe Shake os hfahaha ioe 075
Oxide of iron..... Teh ei’ot ete pele acon aed
Potash Nae cbcas ici evchar soar hecieeeearae 18
AVG LOTA Te ca delcuavcvon Uiacapeeelevaleien era 2
98'5
* See Journ. vol. XXVII, p. 148. + Ib. p, 151.
} See adescription of it, Journ. vol, XXVI, p. 384,
Apatite
ANALYSES OF MINERALS... 233.
Apatite in mass from Uto. Apatite.
Phosphated lime..... eaten nnshiens g2
Carbonated lime. ..........e020: 6
RNa. o aveta bat doen ee eee.
Oxide of manganese, a trace
Loss iffroasting,....2,.e0..0. O08
99'5
Brandschiefer, or bituminous schist, from Wologda. 200 grs. Bituminous
yielded slate,
c.inch, rs,
Sulphuretted hidrogen gas....80 = 28'8
Empyreumatic oi].......... He aoe ORO
An oil as thick as pitch........... 5
Ammoniacal water.......... ae fet ee
Charedal rch ci.. . 2. 0's ssl ie ies ayaa Se
Rea gets ss pap ct es ala ei tee 07'S
PE cue lieve Soelie unt ete OS
PC hao ine od 3.65 aren ota siatens tose! IOS
MP EEICRI A aie sais, fein w Ria pons sem ys iE
Oxide of iron........ siesta tere eeenass ate
196'3
Water from the Dead Sea. Sp. gray. 1'245*. Water of the
Muriated magnesia............ 24:2 Dead Sea.
= limes! t ee
Sodas Tt Se 2 Ek OS 78
PALES DS c-~s-0rorawwiniwhponsw thee. aed:
at
100
Crystallized vitriol of zinc, from Rammelsberg. - Sulphate of
PROPRIGENGE ZINC. .):5'5:s.er, s.xcen Baa ee rey ase
DIANBANCSE, wie cee cisnk | O'S
Bompharie acid. ao of cece oo 22
ASE a AREER, EC ok Ses ORE 50
100
t For avery full account of an analysis of this water by Dr. Marcet,
see Phil, Trans, for 1807, Part II; or Journal, vol, XX, p. 25.—C.
r Roth-
234. ANALYSES! OF’ MINBRALSs
Red silverore, Rothgultigerz.
DRL VETE Ain: asarasoialn.odeyaseio inde eaegeintake 60
Antimony..... ARR iti 19°
BUDE. cca esein pia miesinaemutn ois 17
ORIEN, 0... oc Wed vie W obit led 4:
100
Ore of lead Fibrous arseniated phosphated lead, from Rosier, near Pont
gibaud, in Auvergne.
Orximicnan teed. ol. 5.5 vet Son ae . 76
Phosphoric acid, 5.1. sas: so see
Arsenical acid,..... LENE Wl ey
Miurigtic acides << (2 cas. uo nae ey ee
WET 6 iota bre wis aioe stc fie eee - O50
BOSS. 5. sis: nies iw qinlaiatie-a ocak lela Sa
100°
Ores of tita-’ Tserine.
alum, Oxigiqated TTOO.:. 5 554,60. 02,00 :05 72:
Oxide of titanium,........... 28
100
Granular titanited irom.
Oxidalated trons. cet see seccs Ba
Oxideof titanium.... 2.2.0.0 14
TManganesey'.....0650° OS
*
100
Pitchlikeiron | Ferruginous pecherz, or piciform iron, from Freyberg.
hig Oxidesa@f fon, ,es200050> sane. OM
Sulpbusicacid*; osc ecencecn- 9S
Wratewege oo ia bo colccins bs one me
101
Octaedral crystallized volcanic eisenglanz. Sp. gr. 3°88.
Oxidylated iron,........--ese- G6
Silex... se. e see eeceeee eee ee 29:50
Tri So, oes 6 ace es yon ete 4
Wott oss aa ke hee eon 0°25
99°75
kronglance,
* $o in the French,—C,
Tig
ANALYSES OF MINERALS: 235
Tin: pyrites. ‘Tin pyrites. |
RNG sie sie ag so EEE eS tt
ds vic 4 aad apleenion 6 2
MS se ope heyrcanen aan wale :
TNE os a5 ine)nligningnslg esse S04. SO y
99
Realgar. Realgar,
Metallic. arsenic... ,........-- Prgeey 6.
RRMMARE Ds Sictwrcle nie)s s,'0'9 5 ns a eeel ee
100
Orpiment. , Orpiment.
Metalic arsenic... sce e cc anes 62
MR on 3 Kanan dis.c.0 ya ene 38
. ) ates. Ses
Sphene from Salzburg. Ore of tita-
Oxide of*titanium............- 46 ga
MUR RA .. ceeeitne teres Uucegn | ee
EG DOR fait ania tls Bes 16~
Da, v5 oy 6p w kins woth eeeeos 1
f Meteorolite of
Lissa,
Meteoric stone that fell at Lyssa, in Bohemia, the 3d o
September, 1808*.
MECC dais cin ahs cwarsaeisens | 2
a i sink tte de disivacicce,) OOO
PAANGAVCEE owes ete Salevia. eee
RIE ccke ay Sites 4's ec cittalncae sich: AO
RS er coc insoaleche heat eee
Miiae < S26 eet eee) PES
RN hc e pia itemcewy ce | DO
Sulphur and loss..........5.2- 3°50
190.
* See Journal, vol, XX XI, p. 224: 4
: ot itis Meterolite
2360
Smolensko,
and Stannern.
ANALYSES OF MINERALS,
\
Meterolite that fell in the government of Smolensko, the
15th of March, 1807*.
Trony 28 3). be slater dies Od eelwdtat vat d 17°60
iekcele ic: neiaie stctinetencuie diced Ue 0°40
Silex+. sé. WF deat saint’ Petipa ahaa 38
PU TS ler eon eee Onl IE LS 14°25
Alumimedieiee ais o'aveal ie Caco nee
Limes Bo: sees ap sis ae'onhy Ogos
Oxide of iron: y. . Pt te ae
Sulphur, manganese, and loss.,.. 3
100
Metereolite that fell near Stannern, in Moravia, the 22d of
May, 1808}.
Silexeeie ie B's whoteteld fatal diatatan *
Alumaiive tenn 0a at AEE
hame Ss Ace aUee Sule ca ee eae
Magnesia? suite, US eee
Proms tite aha ss RIS eeiele ve
Loss, including sulphur and
MANQAaNESE wees sseceressevece
48°25
14'50
9'50
2
23
2°75
100
‘
* See Journal, vol. XXV, p. 59.
+ See Journ, vol. XXXI, p, 229; and for analyse
Moser afid Mr, Vauquelin, vol, XXV, p. 56 and 5
s of this stone by Mr.
3.
} Crystallographie
- SCIENTIFIC NEWS. 037
“Crystallographic Models, exhibiting the forms of Crystg ls,
their Production, Geometrical Structure, Transitions of Forms,
and mechanical Dissections. Intended to illustrate the Science
of Crystallography, after the Method of Haiiy. Accompa-
nied witha Treatise elucidating the Elements of that Branch of
Knowledge: By Frepertcx Accum, M. R. I. A. Operative
Chemist and Lecturer on practical Chemistry, and on Mine-
ralogy and Pharmacy.
“In future the name of God, will be as distinctly written on a crystal,’
as it has hitherto been in the Heavens.” Philosoph. Journal, vol.
“ix, p. 87.
To Mr. Nicholson.
SIR,
HE general attention which of late years has been paid to Cultivation of
the science of minerals cannot have escaped the notice aeeti g
of the most superficial observers. No department of natural
history has been cultivated with more ardour and success than
mineralogy, and in none have the cultivators of science been
“more numerous, both at home and on the Continent. It em-
braces a wide circle of votaries among the curious and wealthy
‘classes of the community, and it is intimately connected with
that laudable passion for exploring the productions of nature
‘which characterises the age in which we live. _
Indeed, under whatever points of view we examine the shell Symmetrical
~ of our globe, we are struck with the variety of its productions. oe or cry-
» When we cast our eye over the substances which compose the
- collections of mineralogists, or the cabinets of the curious, we
behold a vast number of bodies, which are regularly shaped, and
exhibit the forms of geometrical solids. The substances are
called crystals.
When we examine the constitution of crystalline solids by General facts
- the methods of chemistry, we become convinced, that the same pacing ER
‘ identical substance, or material, does assume different figures, tiesin the same
- which frequently bear no such resemblance to each other, as Substance.
’ would seem to indicate their relation. And chemistry, or the
- chemical art, is alsocapable of causing bodies to assume symme-
‘trical forms: and the figures of these are likewise liable to be
altered by circumstances, which affect the crystallizing process.
’ Sugarcandy, for example, usually crystallises in oblique four-
3 sided
ir
£238 SCIENTIFIC NEWS.
sided prisms with wedge shaped summits; but it is ‘also niet
with in six-sided prisms variously:modified. ‘Alum crystallises
in octahedrons, but it likewise assumes the shape of a cube, It
is found nevertheless, that a certain number of figurés are
peculiar to each particular crystallisable material ; arid the crys
stals of that substance assume some.one of these forms, or'their
modifications, and no other.
Theelemen- | This however is not all. When we penetrate into the
asain interior structure of these solids, we become convinced, that
symmetry ac- their'mechanical elements are symmetrically placed according
eae to to certain laws, ‘which have ‘their measure and their value.
Their aggregation is absolutely geometrical, and appears as if it
had been effected by «instruments iguided by skill and iatelli-
gence.
—deducible To exhibit these Jaws of crystalline architecture, -is'the spro-
ane vince of crystallography. ‘This science ‘has in our time,been so
successfully cultivated, that it.gives a dignified aspect to the
philosophy of minerals, as grounded upon the results of the most
elaborate and skilful analysis. By these we are enabled to
calculate with the fewest possible data, simple inthe extreme,
and mathematically certain, the vast variety of forms of
crystals, with a like degree of accuracy as astronomers attain in
calculjating the motion of the heavens.
Great advan- But as the knowledge of crystallography in its improved
tages ofmodels state abounds in mathematical and algebraic calculations, and
for expla ning i ,
this doctrine, Cannot therefore be studied with success by such as are unac-
quainted with the mathematics ; it has been proposed to ilus~
trate its elements by the help of geometrical models, which,
in other departments of knowledge, are so singularly useful
in rendering mathematical demonstrations obvious to the sen-
ses. Undoubtedly the human mind is capable of receiving
information from the mathematics with much greater facility
for demonstrations afforded by tangibie solids, than by mere
reasoning from designs drawn upona plane surface. It requires
an eye familiarised with the rules of linear perspective to com-
prehend the diversified and often complicated forms of angular
polyhedrons represented by projections by straight lines only,
which must naturally cross each other in many directions in
the representation of crystalline bodies. \
Advancement ‘Lhe general advancement of science and arts must be.greatly
. dependant
SCIENTIFIC ‘NEWS. 239
dependant on the facility with which their practical‘ means can - — from
‘be obtained. Less'than thizty years ago there were not three eae rinigs
‘places at which the ready prepared materials of philosophical useful means
chemistry could be purchased in ‘this great metropolis. “There ©! Practce-
was but one maker of turning ‘lathes; philosophical instru-
ment makers were very few ; and there were no steam engine
makers, agricultural implement manufactories, &c. in
London, with which we now so plentifully abound. I would
submit to -your consideration, Sir, that he who establishes a
place of fabrication er deposit of an article of use ‘to ‘the
sciences, which could not before be purchased, ts a benefactor
to the public; and under this point of view, I offer you
the present notice, as a piece of scientific news, though it
is likewise of a private commercial nature. I have, with consi-
derable expense and attention, prepared a set of models of
crystals, partly solid and partly dissected ; and have made ar-
rangements, which enable me to supply the public. The dis- Dissected mo-
sected crystals are so.construeted, that they can readily be taken age Py reseed
to,pieces and.built up again in various ways, to give the un-
tutored eye a distinct conception of the laws of that geometry,
which are followed ‘by the integrant particles when they com-
bine, and the orderly arrangement of ‘which produces symme-
trical crystals. And this in fact constitutes the basis of the
science.
A single glance at the dissected models will enable the stu-
dent to ‘comprehend why crystals are always rectilineal bodies,
bounded by planes ; and whencethat immense variety of ac-
tually existing crystalline forms is derived, with which themi-
neral kingdom has hitherto astonished the world. ;
T have likewise composed a treatise, which will form a work Treatise refer-
distinct in itself; but nevertheless so composed, ‘that it may Ay acruase
serve as an index of reference to its models through the work*,
And as the series of solids to be finished.on the present ocea- subscription
sion will be limited, such individuals, who are desirous of re- proposed.
ceiving sets of them, will have the goodness to favour the
author with their orders, either ina direct way, or through
the medium of their booksellers.
*This work, which is in the press, will shortly be published by Messrs.
Longman, Hurst, Rees, Orme, and Brown, Paternoster-row, The copper
plates for the work are engraved by Lowry ; aul the linea! projections
by Berryman and Brandstone.
This
24.0 NOTICES AND CAEN TOD ETN
This condition is essential, because the author presumes he
could otherwse employ his time and labours with more ad-
vantage to himself, and the public. Farther information
may be had at the laboratory, where several thousand models,
both solid and dissected, are ready for inspection.
Iam, Sir,
Your obliged servant,
perigee: § FREDERICK ACCUM.
Old Compton Street, Soho,
October 25th, 1812.
Queries. By Inquisitor.
To Mr. Nicholson.
Sots. Eapinywelivnn, a! 84
* HE following queries are submitted to the scientific eye of
Queries aha. the perusers of your Journal, and an answer solicited by
tural history. IN QUISITOR.
Queries—lIs there a species of lichen, or of amy other crypto-
gamin plant, in the form of a powder, of alight azure colour ?
Or do the ova of any insect, or the insects themselves, exhibit
this appearance ?
Where is the description of such plant or insect to be found ?
{<= For want of room, the accounts of Kirchoff’s diseovery of a process for
converting starch into sugar ; with the experiments and inductions of other
chemists, are deferred to our next.
Dr. Pearson's reply to Dr. Marcet came too late or the present month.
“
The communication and drawing from Mrs. Ibbetson came duly ts
hand, and will be published in our next number.
———
ERRATA IN THE LAST NUMBER, ~
Pp. L.
146 18 For “ rectrified” —_ read rectified.
27 * AS to flziv” Asi) to fisiv.
)
1
— of the-weorel Os ofen prectiiy fme is if LPO |
C c
Mt
vert) i
ead foneeray
Nat me
Philos. Journal VolXSAM. PLV p.240.
| f |
elicaiisg
oe cr D cz E F Fe G o# A a BC ‘Ss
i. | |
| r | I ous | i |
| ‘(EB li TEE Ha ne
\
Fig. 6.
i mf
ad dig he “gt
JOURNAL
NATURAL PHILOSOPHY, CHEMISTRY,
AND
THE ARTS.
DECEMBER, 1812.
ARTICLE I,
On the Growth or Increase of Trees: by Mrs. Acnes Inxer-
“SON.
To Mr. Nicholson.
’
SIR,
HAVE before proved, that there is a vital principle in all
plants, from which all flowers proceed ; from which the
seed is formed, and from which the interior bud is protruded.
_ I have also shown, that in all plants which rise yearly from the
earth, whether annual or perennial, the buds shoot from the
root; butin all trees and shrubs, from the nearest line of life,
which is that vital purt adjoining the pith, The next matter show the
__ of importance to the development of the nature of trees is manner of the
i
to know and understand, as exactly as possible, how they in- ard ag a
erease in size. That the wood is enlarged by an additional cy-
jinder each year, we are well apprised ; and that a new shoot
is formed each spring and autumn, we also know : but here our
knowledge ends. No one has ever attempted to inquire in
what manner that stripe is added, or what preparations nature
makes for the purpose : satisfied with the result, they seek no
farther, though, without knowing it, the existence of a tree is
Vor. XXXIII, No, 154.~DecemBer, 1812, R une
YAQ GROWTH OF TREES,
unintelligible tous. Nor are we informed how nature, in so
hasty a manner, can protrude such a length of shoot as is often
seen, in the autumn particularly. And yet all this is of the ut-
most importance to be known ; it is that leading ray, which
should enlighten all the rest,/and give a more perfect perception
of the formation of that extraordinary production called a tree,
which perhaps may be truly said to collect within itself more
wonders than any other matter whatsoever, and which nothing
but the custom of viewing daily could enable us to see without
constantly increasing astonishment; a being endued with life,
and yet governed by mechanical powers ; capable of selecting
from the juices of the Earth the quantity of sap necessary to
its increase, and yet drawing only that, and adapting its increase
to the quantity drawn ; elaborating its own juices, and by this
means rendering them more suitable to the tender existence of
the new bud, fit to invigorate the flower, and prepare it for the
The mechani- perfecting the seed ; enabling it, by mechanical means, to sup-
Soll eae of port its leaves, that no rain water may drop from them on those
y below, which, if not provided against by nature, would soon
putrefy the lower part of the foliage* ; but by their varied mo-
tion, and mechanical action, so manage, as to throw off toa dis- |
tance the water thus gathered: enabling the leaves to turn in
such a direction, that each may partake of that light absolutely
necessary to the welfare and health of the whole, and though
producing a deep shade for the solace and refreshment of man, :
yet each leaf capable of placing itself so as to receive rays of
that vivifying matter, light, which we every day learn is more
necessary, not only to the animal creation, but also to the vege-
table world. A
For a considerable period my time has been dedicated to the ;
studying the new shoot in trees, watching its daily progress,
marking if witli threads, and then dissecting it in various states
of augmentation. By these means I have, I flatter myself,
gained a tolerably perfect knowledge of the whole proceedings,
* The contrivance selected by nature to enable the leaves of trees to
throw of the rain water which is not necessary to them, is to be found
in ‘the gatherers: they have moments of shaking, which seems tobe 4
caused by some sudden effect of the spiral wire. I have repeatedly ii
placed a paper windmill to ascertain whether it was the effect of wind,
and found it not so, |
2 and.
GROWTH OF TREES. 243
and no part of botanical physiology is more worthy a minute
inquiry. It is an easy matter to establish a beautiful theory to Necessary
captivate the imagination, though without elucidating a single eae oe
fact : but to understand every part of the formation of a plant, a
interior as well as exterior ; to dissect and watch its various
states and changes ; to examine thoroughly how it passes into
each, and what has been the general effect produced in the ve-
getable by such alterations ; to collect by dissection and by cul-
ture its habits and powers—these are the requisites, and all
this must be gained by examination and study, before we can
at last form a theory founded on truth, and learn to know
what a plant really is. This is my aim, and upon this I haye
already employed fourteen years of the most unremitted appli-
cation. J shall now show the manner of a tree’s increase in
every way ; how the. spring and antumn shoots are protruded ;
what is the difference of various trees in this respect, and also
the changes produced in the new shoot, when compared with
the older parts of the tree ; how the yearly stripe in the wood
is contrived, with many other particulars, as they may occur to
me.
If a tree be examined about the beginning of August, it will py. screws
be perceived, that a sort of screw is forming at the end of the which indicate
last year’s shoot. Each different tree has its own peculiar screw, the oa
appertaining to the whole genus. Thus, in the poplar it is long
and seattered ; in the oak, short and close. It is found by many
deep tims, which are partly the outward marks indicating the
bud, but perfectly divided all across the plant, one from the
other, within as well as without. When you take off the bark
and rind from the screw, you find the interior wood swelled
with the buds of the year, which are to develop the next
-spring, and will then be arranged and placed in the bark of the
screw. It is now that you see, inthe most pointed manner, all
J have before shown respecting the buds ; viz. that the wood
vessels open and disperse to let them out ; that the buds possess
all this time no other covering than a few coats of alburnum,
and have no scales till they reach their cradles in the bark ; and
that it isthe thickened form of this bark in each screw, which
allows of the concealment of the buds, where they remain till
they have woven their scales or winter covering, I have said,
that the screw isa collection of rings or links; there is also
R2 a part
Q44, GROWTH OF TREES.
a part attached to each, capable of increase, and which draws
out like a telescope ; this increase is generally the usual distance
allowed to new shoots in every sort of plant between bud and
bud, and of course varies according to the tree. When the
The shooting screw is formed, and the buds arranged in each, then the shoot
ef the screw. begins to push ; and here again great variety is discovered—in
some trees a quarter of a screw divides, and then runs up to
the end of the shoot, forming a long distance between the
buds in each new division, and thus continues to develop till
all the different links are expanded. In the horse-chesnut it
will separate into various pieces ; its leaves and buds growing
from each extremity, equally developing it both ways; but it
may always be known which link, or which part of the screw
is drawing out, by the youngest leaves being in éhat place. In
the ash, nearly half the screw first shoots up to the*termination
of the new branch, and then continues to unfold that piece of
the screw, till it is all expanded ; it then completes the forma-
tion of its winter bud, and when that is once protruded in a
plant, it never shoots a piece beyond it that season. This is the
The new shoot case, I believe, in every forest tree : in all trees the new shoot
ean from differs from the rest, not only in the manner of placing its
leaves, but in the appropriate distance of the buds. In the
oak the leaves are alternate, and there is not half an inch dis-
tance between them : but in a new shoot two leaves come out
almost opposite, or within a quarter of an inch, and then pass
on a full inch before they reconimence their former progress,
The first shoot of the elm is very different ; the leaves are all
twice the size of any other in the tree, and the distanee of the
leaves is in proportion. Also the screw almost always deve-
lops below, at the. part where the new shoot begins, and very
rarely at the extremity of the branch : besides, nature esta-
blishes a curious difference between shooting from an- embryo,
when a treeis first formed, and pushing its half-yearly branch in
spring andautumn. In the first, while yet in the seed, it forms
many buds, and while it is developing its seminal leaves, many
Shooting with. More are added to the number: from this preparation the branch
@ut screws, shoots at once, without waiting to arrange them in screws, be-
cause they then may be said to shoot, like an herbaceous plant,
from the root, which of course they can never do afterward ;
and must be protected by the sheath the leaves always lend to
young
GROWTH OF TREES,
young plants of every kind. It is wonderful to see how nature
adapts her proceedings to the case in point, and how you may
make her vary her modes by changing or altering the situation
to which she is exposed. This is the reason that makes me
so unwilling to trust to any knowledge gained by placing a
plant in an unnatural position, which is certainly the case when
we stop the sap ; arrest the flow of the blood ; varying the
growth of any particular part, or play any tricks of that kind
in order to benefit by the means she will adopt to right herself ;
but we are not enough acquainted with the whole arrangement
of plants, to improve by such a mode of practice: the result
is only formed to lead us into errour ; we misapply the cause, and
245
build a theory on falsehood. The only proper way of studying Necessary to
plants is constant watching and dissection. The person who
will not give up some years to the study, should not attempt it—
but, to return to my subject. It is not only the shoots from the
embryo that come up without a screw ; it is the case also with
hungry branches ; these hasty productions are seldom seen
in forest trees, though minor trees and shrubs are very subject
tothem. Whatever part of the tree may be the base from
which these branches shoot, a quantity of buds is first formed
at that place ; and it is, perhaps, this very cause, that makes them
run up so hastily. The buds being ready, they soon appear at
the extremity of the twig, one by one, till they have expended
give much
time to the
study.
all that were assembled—it is the same also when a stool is wanner of
hewn for procuring trees, or when a pollard is fresh cut ; the shooting in
stools and pol-
large space allows room for such a number of buds to form,
that it appears no longer necessary to arrange them in that exact
manner ; but they run up hastily, and are soon seen rising alter-
nately at the end of the twigs, and developing both buds and
leaves. I have sliced several pollards and stools in this situa-
tion, just as they were going to shoot; and the buds have so
crowded on each other, that it has been absolutely impossible
to count their numbers, This manner, however, of shooting
never takes place above once ; the second time always comes
with the screw as usual. A
T shall now show how the yearly increase of the stripe in the
wood is contrived, which forms the horizontal addition to a
tree in width: it is, if possible, attended with more curious
circumstances than the increase of the new branch—but I
know
lards.
246
Yearly in-
crease of sap.
GROWTH OF TREES.
know not any thing more difficult to discover, or that has cost
me so much trouble to gain ; as it requires so perfect a know-
ledge of the formation of the tree, and the general disposition
of the several parts in each different wood :—but the dissecting
and comparing the shoots of autumn and spring, by fresh vege-
table cuttings, and watching in trees their increase, has at last
enabled me to effect it; and it will be much more easy for a
person to follow me, now the matter is known, than first to
ake the discovery. Choose a tree of any kind that you can
cut to pieces, take off a large branch near the stem at the be-
ginning of August ; between the wood and bark a row of al-
burnum will be found—it is distinguished by being of a clearer
and softer substance than any other in the tree : it is this albur-
num which is deposited each season, half a circle at a time,
and which the next season becomes wood, You will then find
the bark and rind are retired back at the south side of the tree,
leaving a diminutive space between the alburnum and bark,
which is preparing for the season’s increase. It is this
which causes them to be so easily severed, and, makes this the
proper season for barking. Take a vegetable cutting of the
branch, and examine the alburnum in the solar microscope ;
it will appear perfectly clear and free from all vessels, and to be
merely what I before announced it, a jelly of sap. Continue
to cut fresh specimens, and display them daily before good mag-
nifiers, and they will soon show the sap-vessels beginning to
run through this stripe of alournum, and the bastard vessels
shooting also across it, but ina contrary direction. In a fort-
night’s time, that part which was alburnum is now become per-
fect wood, and the jelly of sap will appear to be forming
beyond it, filling up that place from which the bark had re-
ceded for the purpose, and forming a new circle of alburnum,
which the next autumn, in its turn, will be converted into com-
plete wood. This must at once show how the wood and bark
are protruded in trees ; and end that eternal dispute, whether
the bark make the wood, or the wood the bark. It is certain,
that they are of a totally diiferent nature, and yet in one re-
spect agree in their formation. That it is the juices which
form the softer part of each; that these coagulate, and then
wait for the growth of the separate vessels, which shoot out
vessel within vesse), thus lengthening as necessary, and pro-
truding
GROWTH OF TREES.
trading like the new shoot of the spring and autumn, and draw-
ing out like a telescope. This is the manner in which the wood
vessels increase ; the bark vessels are rather different, as I shall
explain at another opportunity. But this is not all which is
47
of consequence to the subject—the retiring of the bark-vessels The retiring
to make way for the new row of alburnum is managed in various i
ways in different trees. In most fruit trees the bark-vessels
bend up, receding from the part the alburnum is to occupy,
and then pushing out towards the rind, and thus increasing the
circle. In forest trees the smaller cross vessels break away, and
Jeave all the circular ones to retire towards the rind. But
whichever way they act, I have a specimen which elucidates
each fact, and makes it beyond contradiction : and it may easily
be seen, that constantly taking the cutting of a branch every
season from the same tree, its incréase, and the manner of it,
must be exactly noted : but it sometimes happens, that the
season is unfavourable, and that the severity of the weather so
checks the sap that should form the new row of alburnum in
March, that it rises not sufficiently to deposit so large a semicir-
cle ; then the old remains on that side, and causes that appear-
ance sometimes found in wood, which presents the yearly circle
incomplete ; but it occurs not often, especially in zndigenous trees.
Nature performs her part too perfectly, unless we make her
fail by removing various trees and shrubs from a more favour-
able climate to our own—then I have seen it produce a strange
effect. Ihave many specimens, in shrubs particularly, where
the pith has been wholly on one side, almost joining the bark,
though twenty or thirty circles, well defined, have shown three
quarters of the year ; but the winter quarter has been as void,
as if it should never have had a mark—this must be wholly
Owing to its missing its spring shoots, from the coldness or
damp of our climate. The exact manner, in which every
branch in a tree tells its own age, is also acurious fact. I have
before observed, that the trunk of a tree shows exactly how
long it has been planted, but the branch shows only the seasons
it has grown, one row for each year. I have taken a whole
tree in this manner, examining each division ; and the exact
way in which it answers to the time of its shooting is curious
to see—the autumn shoot, however, is so much wider than
the
/
back of the
rk,
248
GROWTII OF TREES.
The pith sel- the spring*, that the pith is seldom in the middle of the trunk,
dom in the
middle of a
tree,
except the tree is very strong, and in a very sheltered situation.
But there is another point worthy of attention. / If a deep in-
denture is made in a tree, the mark will go on increasing as
long as the tree continues to grow, just as in a range of circles,
an angle increases from the centre to the circumference. Thus,
if I form across on thestem of a tree, twenty years hence
that mark will show exactly what increase that stem has made in
the middle ; and, by the number of coats laid on it in the wood
part, how many years since it was first indented. But it cer-
tainly appears, on first consideration, most wonderful, that it
should do so, considering the extreme change each fibre
undergoes, and how often every part must be moved to let the
buds pass out from the interior; but on examining a tree barked,
the miracle ceases—when once an impression is made, every
succeeding cylinder is so conttived, that it must enlarge the
mark by the progressive motion of the parts, the very thin
layers that are added each year, and the forcible and perpetual
compression the whole undergoes. It is the same with many
natural marks formed by the missed buds or bulbs, the existence
of which I have before shown, or any other accidental impression
The effect of inatree. This natural effect was productive of a very curious
cutting matks consequence during the time of irreligion and riot in France.
.On a tree.
A poor widow cleaving a tree to procure some fire-wood to sell,
found the mark of across in the interior of the trunk of an
ash—she never looked at the rind to seek a correspondent im-
pression, but took it for a miracle, a declaration of the Al-
mighty. All the people crowded to see it ; the widow was
soon enriched, and it hada better effect on their morals, than
all the edicts in favour of religion afterward promulgated by
Bonaparte, or the horrid experience of times divested of all
piety.
* It is astonishing, how many exotic shrubs, and even trees, grow
only in the autumn, and miss their spring shoots, and have, therefore,
the pith quite on one side. I have traced this in a number, and, by
taking'them at the proper time in several different specimens, secured
the most absolute proof, that this is the manner in which they increase :
thistruth, therefore, like the coming out of the bud from the interior,
cannot be denied, since no tree or shrub can be examined, without
proving it.
But
GROWTH OF TREES.
But that wood ever so old should get into that torpid state
described by some botanists, is certainly a very gross mistake :
as soon as the sap ceases to flow, the pipes decay, the rot is in-
troduced, and death ensues : for when all motion ceases in the
wood, it can no longer divest itself of those minute pasts, which,
accumulated, would soon cause itsruin. There are little fibres
which join together the bastard vessels, and are constantly re-
newed every few years, decreasing in length as the compression
of the wood makes it necessary. Their motion, therefore, in
letting out the buds also divests them of their extraneous matter,
which would otherwise fill up the places left for the new shoot
of alburnum : but let the age be ever so advanced, the stems
will throw out new branches, the line of life new buds.
I have a log of a tree adjoining the trunk, with above ninety
yearly circles where there are two or three large buds pro-
truding, and the wood vessels making way, as in quite young
trees: but that there is some age at which the wood ceases to
form in width, there can be no doubt. I think I have traced
its manney of proceeding in this respect—but I have so seldom
an opportunity of gaining a fit specimen froma very old tree,
to ascertain the truth, and am so unfortunately circamstanced
for procuring any thing of the kind, (although ever so much
wanted.) that few would have the courage to study, so sur-
rounded with obstacles. Ina specimen known to be between
two and three hundred years old, I have got a vegetable cutting :
for eighty years it proceeds in the common manner—then the
rows increase, not in the usual place, but between the others,
forming five between each row—this continues for near thirty
years ; then it passes on to the old place between the bark and
the wood, and increases only on the south side of the tree
each autumn, without any sort of addition in the spring, or
north quarter. This goes on about sixteen or eighteen years,
when an entire stop to the growtb seems to take place in width—
it may then be supposed, that the tree, having attained its perfect
size, stops for a certain number of years, and then begins to
decline, still throwing out buds and branches, and never too
old for this, since the oldest possible tree, if freed from rot, and
_ having the exterior pared, and a plaster put on, would form
new wood, and generate a quantity of buds. I have tried this
in such extremely old subjects, that I am convinced it is part of
the
249
No torpidity
in wood.
Get rid of éx-
traneous mat-
ter,
Shooting on
thesouth side
ouly.
Ili usage of
‘trees.
Drawing to il-
lustrate the
manner in
which trees ip-
crease in
growth,
GROWTH OF TREES.
the wonders of the vegetable ; and that if, therefore, trees were
taken care of, they would die only at a very old age. But few of
our trees are allowed to gain maturity : we, indeed, use them so
shockingly ill, that there is no chance of their reaching to such
a time of decay. If noblemen and gentlemen, instead of plant-
ing such a number of trees, would Jessen the number, and take
care of those growing—be as saving of them as of their game—
make itthe business of the land steward, or bailiff, or game-
keeper, to see that no trees are damaged, or allowed to decay
before their time—that the unprofitable branches are lopped,
the cankered arms cut off, the withered tops curtailed—that the
trunk is not allowed to form holes, or to split, without being
joined and plasiered—that they are, when first growing, cleared,
the sun, air, and wind admitted to them (for to this last they
owe their being saved from vermin and blights)—But I mean
not now to enter on a farther discussion of this matter—my
present subject is not the preservation, but the increase of the
tree, which strictly examined by the rules, and in the manner I
have advised, will, I flatter myself, be found exactly conformable
to truth, and delineated with as much precision as the difficulty
of the subject will permit,
I am, Sir,
Your obliged Servant,
AGNES IBBETSON.
Description of the Drawings.
I shall now give the drawings, grieved that it is not in my
power to show them in their natural state ; for to argue from
living specimens at once makes all contradiction impossible, and
is as delightful to the teacher as to the instructed. Pl. VI, fig. 1,
is the screw of the beech with the winter bud already formed :
it is much magnified, and the three leaf-stalks show the manner
in which the old branch shoots in the beech, while fig. 2 is the
way the new shoot throws out its leaves ; in the old parts the
leaves are in threes or fours ; in the new shoot the leaves are
always alternate, with a distance of an inch and a half between.
Fig. 3 is part of the same branch laid open, with the buds in
their cradles, and with the divisions that show completely how
they are to shoot at BBB : and CCC, buds more advanced, with
the line of lifeleading to each bud at DDD. Fig. 4 are three
screws of the same without the outward marks of the buds
(that
GROWTH OF TREES.
251
(that it may not confuse), only showing the piece which will Drawing to il-
draw up or increase : there should be an inch and a half between mail eRe
t 3 : 4 P bn in
each in the natural size ; from E to E is the lengthening piece. which trees in-
Fig. 5 shows the way the wood increases in the contrary direc- Crease in
tion, I mean in width. FF isthe row of alburnum deposited ®
last autumn, and to be completed ¢his, which is now done at
GG; while the bending up of the bark-vessels at HH allows
the sap to deposit a new row of alburnum at II, which is also
seen at fig. 6, where the bending of the bark-vessels leaves it
‘free. They are soon straightened at K, by the enlargement of the
side of the circle, which the next spring will be made even by
another row on the north side. Fay. 7 shows the increase on
one side only, when the climate prevents exotics from receiving
their spring shoots in width, and this is no very uncommon
case. I have many specimens of the kind by me. Fig. 8
shows the manner of forming the circles—when a tree is past
eighty, it then marks its lines between the others. But I have to
get more specimens, which will complete my kngwledge in this
respect, which is yet partly but conjeciure, and therefore not
wholly to be trusted to. Fig. g is the manner in which the
wood-vessels draw one out of the other ; but as they lengthen,
the upper ones soon decrease to the smallest size.
st ce
i:
Some Horticultural Observations, selected from French Authors.
By the Right Hon.~ Sir Joseru Banxs, Bart, K. 8.
PR. SS. Sc*
Peaches.
HOUGH the English, excel in many branches of hort:-
culture, there are others in which they are materially out-
rowth.
Attention to a
done by the French. Absolute perfection in any branch of an particular
art, so extensive as that of gardening, cannot be obtained by a branch of gar-
person, who allows his talents to range over every part of it. |
dening alone
eads to per-
This the French knew long ago, and have regulated their prac- fection.
tice accordingly. The English have not yet begun this subdi-
vision of skill. Gur fruit gardeners, who carry every sort of
fruit to market of a good quality, cannot be said to have
* Trans, of the Hort. Soc, vel. i, App. p. 4
brought
252
Peaches only
cultivated at
Montreuil.
Soine of tl
best raiseu
fromthe stone,
Almond the
best stock for
budding.
HORTICULTURAL OBSERVATIONS FROM FRENCH AUTHORS,
brought any one kind to absolute perfection. In France, whole
villages are employed in the culture each of one single kind of
fruit. In consequence of this arrangement, the fruits, under
the management of individuals, who for many generations have
exerted their whole energies to this ene point only, are brought
to a degree of perfection, which can never be attained in a
garden, where fruits and vegetables of all sorts must be pro-
vided by one man, for a large and opulent family, or for a weekly
market,
At Montreuil*, a village near Paris, the whole population
has been maintained, for several generations, by the cultivation
of peaches, which is their sole occupation. It is there alone,
where the true management of this delicious fruit can be stu-
died and attained ; for it is impossible, from written precepts,
to acquire the whole.art. ‘The modes of winter and ef summer
praningt are varied not only according to the differences of
soil and of exposure, but even according to the state and con-
stitution of each individual tree.
Some of the best of their fruits are never budded, but
always reared from the stone ; the rest are budded on stocks of
a half wild peach, called peche de vigne.
Peach trees, budded on an almond stock, are larger and more
durable than others; but they require a deep and light soil,
and do not fruit so soon. The best almonds for stocks are the
* An English tourist tells us, that he had stored his carriage with
peaches, which he thought excellent; when he arrived at Montreuil, the
inhabitants there, who offer their fruit for sale to travellers, told him
that he would, if he tasted one of theirs, throw those he had got out of
his chaise ; which, in fact, he did, as soon as he had tasted a Montreuil
peach.
‘Two modes of ' t Fruit trees may, in respect to their mode of bearing, be divided
bearing in
fruit-trees,
into annuals or biennials, Figs, walnuts, &c., are annuals, that is, they
bear their fruit on the branches of the present year; peaches and pears,
&c., are biennials, thei: fruit is produced on wood of the second year’s
growth. In this case much advantage is derived from the practice of
rubbing off the leaf buds of the fruit-bearing branches, leaving only as
many as are wanted to produce wood for the succeeding year. This,
no doubt, is the éaille d'été of the French; it does not only leave the
remaining wood to grow stronger, and to ripen sooner, but it materially
increases the size of the fruit. The French use this method with their
Jigs, as is noticed in page 254.
red
HORTICULTURAL @BSERVATIONS FROM FRENCH AUTHORS. 953
red-shelled sort, and some prefer the bitter; but it is more
difficult to succeed with these, than with the soft-shelled
almond,
_ Stocks of the apricot, and of the prune de St, Juliers, produce Apricot and
smaller trees, that bear sooner, but do not last so long, and, of Pum stocks.
course, answer better in a shallow soil.
The season of budding depends on the weather being more or Season of bud-
Jess wet ; the end of July, in ordinary years, is proper for the 4i78-
plum stock, that for the @pricot and the almond stock is later :
_ and for the young almond stock, the middle of September is the
_ most proper.
| In order to provide stocks, the fruit stones are sown in bas- Raising stocks,
kets; which, when the tree has attained a proper size, are
sunk in the ground where it is intended they should grow, pro-
vided the soil is deep; for shallow soils the young plant is
taken up, and its larger roots cut off, which forces it to throw
out Jateral roots, and in the event to become a more productive
bearer. pe
The climate of France is certainly better suited to the culture The séees in
of the peach, than that of England, as some sorts produce Saar e
their fruit there in perfection on espaliers, and a few on stand- ARS, frost.
ards in the open air. The people of Montreuil are, however,
abundantly more careful, than we are, to protect their trees
- from the action of frosts, during the time of flowering: at that
time a very slight degree of frost is apt to seize upon the pistil ;
and ifthe sun shine upon the flower before it is entirely thawed,
‘this organ loses its power of receiving the pollen, and the
_ flower, in consequence, drops off without setting its fruit.
To guard against this, the tops of the peach walls are fur- Modes of
nished with long wooden pegs, or with iron wall-hooks, on 21g this.
which planks are fixed ; and on them straw mats are hung in
such a manner as to be rolled up or let down at pleasure.
' Those who do not use this precaution, light fires with damp
‘straw in such a manner, that the smoke may pass over the
flowering branches at sun-rise. This intercepts, in some de-
“gree, the direct rays of the sun, and, by its gentle warmth,
thaws the frozen pistils by gradual and slow degrees ; others
fasten the branches cut from ever-green trees, with their leaves
‘upon them, in front of the peach trees, to break off the cold
‘air. :
Peaches
945A HORTICULTURAL OBSERVATIONS FROM FRENCH AUTHORS.
He i pai Peaches are never eaten in perfection if suffered to ripen on
ripenonthe the tree; they should be gathered just before they are quite
tree, soft, and kept at least twenty-four hours in the fruit chamber.
Figs.
Figs cultivated The inhabitants of Argenteuil, near Paris, derive their chief
at Argentenil. support from the culture of fig trees ; near that town are im-
mense fields covered with these trees, on the sides of hills
facing the South, and in other places sheltered from the North —
and the North-west winds. |
The branches Inthe autumn the earth about the roots of these trees is |
buried to pro- stirred and dug ; as soon as the frosts commence, the gardeners
nponaie a bend down the branches, and bury them under six inches of
mould, which is sufficient to preserve them from being frozen.
The branches must be entirely stripped of their leaves
before this is done; the gardener then, taking hold of the top §
of each branch, bends it down gradually, and with much care, §j
to prevent its breaking, placing his knee or his hand under J
such parts as resist the most ; the branches that will not bend
low enough to be buried are cut off close to the ground.
A fig-tree will remain buried in this manner seventy-five or
eighty days without harm ; when the season is mild, the gar-
2 deners uncover them, especially in times of warm rains, but —
on the first symptoms of frost they are again buried. Severe §
frosts sometimes reach them, but the branches only are de- |
stroyed. The roots produce anew crop in the summer; but |
these do not bear fruit till the next year, and are more tender
and liable to be killed by frost during the next winter, than
older and more woody branches. | |
Deatiinds In the spring the trees are carefully inspected ; and where a §
pinched out double bud is observed, the gardeners, who are able to distin-
eee ans guish a leaf-bud, which is more sharp, from a fruit-bud,
which is rounder, pinch out the leaf-buds without hurting the #
fruit-buds; these, as they receive the sap prepared by the
plant for two purposes, produce fruit of double the ordinary
size; this is done at Paris between the first and the tenth of
June ; but these leaf-buds may be suffered to expand a little,
till they can be distinguished with certainty ; they must not be §
all destroyed at the same time. In cool seasons, the ripening
of
HORTICULTURAL OBSERVATIONS FROM FRENCH AUTHORS. O55
of the fruit is hastened by inserting a drop of oil in the eye, Artificial ri-
from the point of a pen, or tooth-pick. pening.
It is n¢cessary in dry seasons to water jig trees; the nature In dry seasons
| of the plant requires to have its root cool, while its head is ex- they require
_ posed to the hottest sun. If planted against the south wall ofa
water.
house near a spout that brings water from the roof, it thrives Gooq situa-
i
luxuriantly. Figs do well also in a paved court; the stones tions.
keep the ground under them moist and cool, while the
surrounding buildings reflect and increase the heat of the sun’s
rays.
Apricots.
Our icnets believe that the Moor-park apricot is the fruit Apricot.
called abricot péche by the French; but this is a mistake, the
abricot péche is a large tree, which may be raised from the
stone without grafting ; it ripens later than the rest, not till the
end of August. The stone is so soft, that a pin, will pierce
through it; the kernel is bitter.
Pears.
The crassane may be improved, and all its harshness de- Pear.
_ stroyed, by grafting upon the doyenn¢é, a pear known in our
if n
elgg Se cS eS sis
gardens.
Apples.
The golden pippin. (reinette d’ Angleterre) is described not Golden pip-
_ only as an excellent'fruit, but as a very productive bearer ; in Pi
_ England it appears to be in its last stage of decay. It is pro-
_ bable that trees decay by age sooner in colder than in warmer
climates.
The French do not suffer their apple or their pear trees, to shape givento
if form wild heads as ours do, and shade all things planted near standards.
them; their standard trees, of all kinds, when in gardens, are
"trained i in such manner as to cast the least shade possible. A
form like a pyramid, called by them quenoutlle, is very gene-
i ‘rally used,
Plums,
‘The green gage, called in French la reine Claude, is much Green gage.
“improved, if grafted on an apricot or apeach stock*.
Maixe,
_. * The name of green gage is said to have originated from the fol- Etymology.
res)
Gr
[=>
HORTICULTURAL OBSERVATIONS FROM FREN€H AUTHORS.
Maize, Egg Plant, and Sweet Potatoes.
All these plants are reared for use in some kitchen gardens
of France, though probably not in many.
Indian corn, Maize is sown in the ground, without heat ; when the spike
is about half an inch thick, it is eaten fried in butter, as arti-
chokes are, or made into pickle with vinegar. _
Egg plant. The egg plant is called in the gardens la plante qui pond.
The seeds of this, as of the other varieties of solanum, are
sown on a hotbed, in March; the plants, when ready, are
transplanted into pots, and plunged in a gentle heat ; after the
plant has advanced considerably, it may be placed in the open
air. The fruit is much used for ragouts in Provence.
Sweet potato, The sweet potato* is planted on a hotbed in the middle of
April, in about six inches of mould: when the shoots are eight
or ten inches long, they may be taken up, and replanted in a
bed of light mould, in the open air, about eighteen inches
deep : all the leaves, except the uppermost, are first to be taken
off, and the shoot then buried so deep, that the small bunch of
leaves only appears above ground.
~~ In October the tubers are ripe and ready to be dug up; in
doing this, the greatest care must be taken not to wound the
‘skin, as the slightest scratch disposes them to rot.
They must be kept free from frost and damp ; if exposed to
either of these, they exhale an odour like that of the rose, and
rot immediately. Both the yellow and the red variety are
cultivated in France ; the red is preferred.
t Straw berries.
Alpine straw- The French cultivate the alpine strawberry in the mode
berry. recommended by Mr, A. Knicurt in the Horticultural Trans-
actions}, and find the fruit so much better when produced by
lowing accident. The Gage family, in the last century, procured from
the monks of the Chartreuse, at Paris, a collection of fruit trees : these
arrived at their mansion of Hengrave Hall, with the tickets safely
affixed to them, except only the reine Claude, the ticket of which had
been rubbed off in the passage. The gardener being, from this circum-
stance, ignorant of the name, called it, when it bore fruit, the green
gage.
* Convolvulus batatas, L. t Journal, vol, xxix, p. 214.
2 seedlings
.
MORTICULTURAL OBSERVATIONS FROM FRENCH AUTHORS,
seedlings of the first year, that they seem to prefer the alpine to
all other sorts, and to be supplied at market with the fruit of it
in every month of the year, by the use of some heat in the
winter, :
The seeds, they say, may be sown either in a little heat, or in
the open air, but always in the shade; they should be sown in
sifted mould, and scarcely covered ; have a thin layer of moss
strewed over them, and they ahogld be frequently moistened,
Fresh seed grows up ir eighteen days : old seed is much slower.
The runners must be.carefully removed.
The market gardeners near Paris sow theirs twice a year, in
March, and toward the end of August; in six weeks they are
large enough to be transplanted, which is done at eight ifiches
apart, Those sown in March, fruit in May and June; those
sown in dugust, the spring following. See Traité des Arbres,
p-9. I rather suppose that the plants sown in March give their
fruit in autumn,
It is good to sow strawberries within the distance of five or
six feet from a north or a west wall ; in the latter case, the moss
is absolutely necessary. The plants grown from the Marc
sown seed must be well watered through the summer; in hot
weather twice a day, if they are expected to bear in the
autumn. The French seem to find the August sowing most
productive. Even in the autumn, in the almanac called Le bon
Jardinier, the author tells us to sow the seeds of strawberries in
February, if we have not done it in the preceding August.
Sowing the
seed.
a
The hautlois is called in French, caperonier ; it is lately only prautbois and
that we have observed an hermaphrodite variety, which bears
abundantly ; in fact, the plant is polygamous: this the French
have long known, and they say that the Chili strawberry is also
polygamous, and that the females may be made fertile by the
Chili straw-
erry.
impregnation of the male flowers of the hautbois. ©
Y
Vou. XXXII, No. 154.—Dscemzer, 1812. S$ Farthe
258 ACTION OF POISONS ON THE ANIMAL SYSTEM.
Ill.
Farther Experiments and Observations on the Action of Poisons
on the Animal System. By B.C. Bropiz, Esq. F. R. S.
Communicated to the Society for the Improvement of Animal
Chemistry, and Ly them to the Royal Society*.
Former obsor- =I. INCE Thad the honour of communicating to the
ae OM poi- Royal Society some observations on the action of cer-
; tain poisons on the animal systemt, I have been engaged i in the,
farther prosecution of this inquiry. Beside some additional
experiments on vegetable poisons, I have instituted several with
a view to explain the effects of some of the more powerful
poisons of the mineral kingdom. ‘The former correspond in
their results so nearly with those which are already before the
public, that, in the present communication, I shall confine my-
self to those which appear to be of some importance, as they
more particularly confirm my former conclusions respecting
Rhcoveer the recovery of animals apparently dead, where the cause of
from apparent death operates exclusively on the nervous system. In my expe-
death. riments on mineral poisons, I have found some circumstances
Effects of mi- Wherein their effects differ from those of vegetable poisons,
neral and ve-and of these I shall give a more particular account. What-
Aa a "ever may be the value of the observations themselves, the
medicine may subject must be allowed to be one that is deserving of inves-
abeimproved tigation, as it does not appear unreasonable to expect, that
ee ae such investigation may hereafter lead to some improvements
‘ in the healing art. This consideration, I should hope, will be
regarded as a sufficient apology for my pursuing a mode of
inquiry by means of experiments on brute animals, of which
we might well question the propriety, if no other purpose were
to be answered by it than the gratification of curiosity.
Former ac- In my former communication on this subject, I. entered into
count given gq detailed account of the majority of my experiments. ‘This I
moreat large conceived necessary, because in the outset of the inquiry I had
been led to expect, that even the same poison might not always
operate precisely in the same manner ; but | have since had
* Phil. Trans, for 1812, p. 205,
+ Phil. Trans, for 1811, p. 178; or Journal, vol, XXX, p. 295, 324.
abundant
ACTION OF POISONS ON THE ANIMAL SYSTEM. 259
abundant proof, that in essential circumstances there is but little but the effects
variety in the effects produced by poisons of any description, Of poisons dif-
when employed on animals of the same, or even of different fe DOG ti
species, beyond what may begeferred to the difference in the
quantity, or mode of application of the poison, or of the age
and power of the animal. This will explain the reason of my Hence fewer
not detailing, in the present communication, so many of the cents ai
individual experiments from which my conclusions are drawn, ve ear
as in the former : at the same time I have not been less care-
ful to avoid drawing general conclusions from only a limited
number of facts. Should these conclusions prove fewer, and
of less importance than might be expected, such defects will,
I trust, be regarded with indulgence, at least by those who are
aware of the difficulty of conducting a series of physiological Difficulty of
experiments ; of the time which they necessarily occupy ; of Physiological
the numerous sources of fallacy and failure which exist; and bait nie
of the laborious attention to the minutest circumstances, which
is, in consequence, necessary, in order to avoid being led into
errour.
IT. Experiments with the Woorara.
In a former experiment I succeeded in recovering an ani- Artificial re-
mal, which was apparently dead from the influence of the pita ate: see
essential oil of bitter almonds, by continuing respiration arti- rma from ihe
ficially until the impression of the poison upon the brain had Poison of Bit
ceased ; but a similar experiment on an animal under the in- perenne
fluence of the woorara was not attended with the same suc- that of woo-
cess. Some circumstances led me to believe, that the result ae
of the experiment with the woorara might have been different
if it had been made with certain precautions ; but I was unabie
at that time to repeat it, in consequence of my stock of the
poison being exhausted. I have since, however, been able to
procure a fresh supply, and I shall relate two experiments
which I have made with it, In one of these, an animal appa- yet it has final-
rently dead from the woorara, was made to recover, notwith- Reta
standing the functions of the brain appeared to be wholly sus- Snag
‘pended fora very long period of time; in the other, though
ultimate recovery did not take place, the circulation was main-
tained for several hours after the train had ceased to perform
its office.
$2 Expe-
260
a
ACTION OF POISONS ON THE ANIMAL SYSTEM.
Exp.1, Acat Experimené 1. Some woorara was inserted into a wound in
poisoned with
woorara.
a young cat. She became affected by it in a few minutes, and
lay in a drowsy and half-sensible state, in which she continued
at the end of an hour and fifteen*minutes, when the applica-
tion of the poison was repeated. In four minutes after the
second application, respiration entirely ceased, and the animal
appeared to be dead ; but the heart was still felt acting about
one hundred and forty times in a minute. She was placed in
a temperature of 85 of Fahrenheit’s thermometer, and the
lungs were artificially inflated about forty times in a minute.
The heart continued acting regularly. _
When the artificial respiration had been kept up for forty
minutes, the pupils of the eyes were observed to contract and
dilate on the increase or diminution of light ; saliva had flowed
from the mouth, and a small quantity of tears was collected
between the eye and eyelids ; but the animal continued per-
fectly motionless and insensible.
At the end of an hour and forty minutes, from the same
period, there were slight involuntary contractions of the
muscles, and every now and then there was an effort to
breathe. The involuntary motions continued, and the efforts
to breathe became more frequent. At the end of another hour
the animal, for the first time, gave some signs of sensibility
when roused, and made spontaneous efforts to breathe twenty-
two times ina minute. The artificial respiration was discon-
tinued. She lay, asif ina state of profound sleep, for forty
minutes, when she suddenly awoke, and walked away. On
the following day she appeared slightly indisposed; but she
gradually recovered, and is at this time still alive and in health.
Exp.2,Arab- Experiment 2. Some woorara was applied to a wound in a
bit.
rabbit. The animal was apparently dead in four minutes after
the application of the poison ; but the heart continued acting.
He was placed in a temperature of gO’, and the lungs were arti-
ficially inflated. The heart continued to act about one hundred
and fifty times in a minute. For more than three hours the
pulse was strong and regular; after thisit became feeble and
irregular, and at the end of another hour the circulation had
entirely ceased. During this time there wasno appearance of
returning sensibility.
The circulation of the blood may be maintained in an animal
frora
ACTION OF POISONS ON THE ANIMAL SYSTEM. 261
from which the brain has been removed for a considerable, The circula-
but not for an unlimited, time. We may conclude, that in the ey Ma
: : , ept up
last of these experiments the animal did not recover, because above a cer-
the influence of the poison continued beyond the time dufing ‘#\2.ue with
: : Hy HE 2 out the brain.
which the circulation may be maintained without the brain.
III, On the Effects of Arsenic.
When an animal is killed by arsenic taken internally, the Two opinions
stomach is found bearing marks of inflammation ; and it is a Of the effect of
very general opinion, 1, that this inflammation is the cause of —
death : 2, that it is the consequence of the actual contact of
the arsenic with the internal coat of the stomach. But jn se- Death is not
veral cases I haye found the inflammation of the stomach so th¢ tesult of
c ‘ Hatin inflammation
slight, that on a superficial examination it might have been of thesto-
easily overlooked ; and in most of my experiments with this ™#°b-
poison death has taken place in too short a time for it to be
considered as the result of inflammation : and hence we may
conclude, that the first of these opinions is incorrect ; at least as
a general proposition.
Many circumstances conspire to show, that the second of The inflam-
these opinions also is unfounded. mation, abs
In whatever way the poison is administered, the inflamma- ed by the con-
tion is confined to the stomach and intestines—I have never (°°: or HE tn
seen any appearance of it in the pharynx or cesophagus.
Mr. Home informed me, that in an experiment made by If applied to a
Mr. Hunter and himself, in which arsenic was applied to "Pehe od viene
wound in a dog, the animal died in twenty-four hours, and the inflamed.
stomach was found to be considerably inflamed.
I repeated this experiment several times, taking the pre-
caution always of applying a bandage, to prevent the animal
licking the wound. The result was, that the inflammation of
the stomach was commonly more violent and more immediate,
than when the poison was administered internally, and that
it preceded any appearance of inflammation of the wound*.
; Some
* Since the greater part of my experiments on this subject were made, Dr. Jaeger of
I have seen an account of an inaugural dissertation on the effects of the same opi-
arsenic, by Dr. Jaeger of Stuttgard. Dr. Jaeger has come to conclu- rir Nesey the
sions similar to those above stated, that in an animal killed by arsenic, u
the inflammation of the stomach is not the cause of death, and that the
poison
262 ACTION OF POISONS ON THE ANIMAL SYSTEM.
Vegetable poi- Some experiments are already before the public, which led
sons acton the me to conclude, that vegetable poisons, when applied to
system : : :
throughthe | wounded surfaces, affect the system by passing into the cir-
blood : culation through the divided veins. From this analogy, and
from all the circumstances just mentioned, it may be inferred,
so does arse- that arsenic, in whatever way it is administered, does not pro-
nic. duce its effects even on the stomach until it is carried into the
blood.
How far the But the blood is not necessary to life, except so far asa
se on constant supply of it is necessary for the maintenance of the
functions of the vital organs. The next object of inquiry
therefore is, when arsenic has entered the circulation, on what
organs does it operate, so as to occasion death ?
Arsenic causes. When arsenic is applied to an ulcerated surface, it produces
a aoe "°'a slough, not by acting chemically, like caustics in general,
but by killing but by destroying the vitality of the part to which it is applied,
oe ae independently of chemical action. This led me at first to
suppose, that, when arsenic has passed into the circulation,
death is the consequence, not so much of the poison disturb-
Acting asa ing the functions of any particular organ, as of its destroying
Ree adic 11 at once the vitality of every part of the system. The follow-
the lite of ing circumstances, however, seem to show, that this opinion
saat part a is erroneous. Inan animal under the full influence of arsenic,
: even to the instant of death, some of the secretions, as those
of the kidneys, stomach, and intestines, continue to take place
in large quantity ; and the muscles are capable of being ex-
cited, after death, to distinct and powerful contractions by
means of the Voltaic battery.
Exp. 8. Arse- Experiment 3 Seven grains of the white oxide of aiseuig
nic applied to were applied'to a a wanna in the back of a rabbit.
a woundina
rabbit. In a few minutes he was languid, and the respirations were
| small and frequent. The pulse was feeble, and after a little
time could not be felt. The hind legs became paralysed*.
ive . . He
poison does not produce its fatal effects until it has entered. the circula-
tion, I have to regret, that I have had no Toppensunit y of seeing the
original of this dissertation, ‘
The influence * Ihave observed, that, where the functions of the brain are disturbed,
ofthe brain: paralysis first takes place inthe muscles of the hind legs; alterward ia
less easily con- those of the trunk and fore legs; aud last of all in the muscles of the
BE ; ; ears
ACTION OF POISONS ON THE ANIMAL SYSTEM.
He grew insensible, and lay motionless, but with occasional
convulsions. At the end of fifty-three minutes from the time
of the arsenic being applied, he was apparently dead; but on
opening the thorax, the heart was found still acting, though
very slowly and feebly. A tube was introduced into the tra~
chea, and the lungs were artificially inflated ; but this appeared
to have no effect in prolonging the heart’s action. On dis-
section, the inner membrane of the stomach was found slightly
inflamed.
263
Experiment 4. ‘Two drams of arsenic acid dissolved in six Exp. 4. Arse
ounces of water were injected into the stomach of a dog, by
nic injected
into the sto=
means of a tube of elastic gum, passed down the cesophagus. mach of a
In three minutes he vomited a small quantity of mucus, and this dog:
occurred again several times. The pulse became less frequent,
and occasionally intermitted, At the end of thirty-five minutes
the hind legs were paralysed, and he lay in a half sensible
state. At the end of forty-five minutes he was less sensible ;
_ the pupils of the eyes were dilated ; the pulse had fallen from
140 to 7Oin a minute, and the intermissions were frequent.
After this, he became quite insensible; convulsions took
place, and at the end of fifty minutes, from the beginning of
the experiment, he died, On opening the thorax, imme-
diately after death, tremulous contractions of the heart were
observed ; but not sufficient to maintain the circulation. The
stomach and intestines contained a large quantity of mucous
fluid, and their internal membrane was highly inflamed.
These experiments were repeated, and the results, in all The experi-
essential circumstances, were the same. The symptoms pro-
the other parts of the body ; convulsions ; dilatation of the
pupils of the eyes ; insensibility ; all of which indicate disturb-
ance of the functions of the brain: 2, a feeble, slow, inter
mitting pulse, indicating disturbance of the functions of the
heart. Where the heart has continued to act after apparent
ments repeated
, ‘ with similar
duced were, 1, paralysis of the hind legs, and afterwards of lalla:
ears and face. These facts seem to show, that the influence of the veyed to res
brain, like that of the heart, isnot propagated with the same facility to mote parte,
the distant as to the near organs ; and this is farther confirmed by cases
of d’sease which occasionally occur, in which, although the paralysis is
confined to the lower half of the body, the morbid appearances met
with on dissection are entirely confined to the brain,
death,
saved
ts
oO)
pee
ACTION OF POISONS ON THE ANIMAL SY6TEM.
death, I have never, in any one instance, been able to pro-
long its action by means of artificial respiration. 3, pain in
the region of the abdomen; preternatural secretion of mucus
from the alimentary canal ; sickness and vomiting in those
animals which are capable of vomiting; symptoms which arise
from the action of the poison on the stomach and intestines.
There is no difference in the effects of arsenic, whether it is
employed in the form of white oxide, or of arsenic acid, except
ae 4p- that the latter is a more active preparation. When arsenic is
wounds acts @pplied to a wound, the symptoms take place sooner than
most speedily. when it is given internally ; but their nature is the same.
tig ofarse- The symptoms produced by arsenic may be referred to the
- influence of the poison on the nervous system, the heart*, and
the alimentary canal. As of these the two former only are
concerned in those functions which are directly necessary to
life, and as the alimentary canal is often affected only in a
slight degree, we must consider the affection of the heart and
nervous system as being the immediate cause of death.
In every experiment which I have made with arsenic, there
were evident marks of the influence of the poison on all the
organs which have been mentioned; but they were not in all
cases affected in the same relative degree. In the dog, the
affection of the heart appeared to predominate over that of the
brain, and on examining the thorax immediately after death,
this organ was found to have ceased acting, andin a distended
state. In the rabbit, the affection of the brain appeared to
predominate over that of the heart, and the latter was usually
The heart in * When Isay, that a poison acts on the heart, ide not mean to imply,
some respect that it necessarily must act directly on the muscular fibres of that organ.
independent It is highly probable, that the heart is affected only through the medium
foto ce nh of its nerves; but the affection of the heart is so far independent of the
nervous sys- affection of the nervous system generally, that the circulation may cease
rem, although the functions of the brain are not suspended, and ihe functions
of the brain may be wholly suspended without the circulation being at
all disturbed. _In proof of the first of these propositions, Imay refer to
my former experiments on the upas antiar, in which the sensibility of
the animal continued to the very instant of death ; and respiration,
which is under the influence of the brain, continued even after the heart
had ceased to act. In preof of the second, I may refer, among many
others, to the experiments detailed in the Croonian Lecture for 1810.—
{Phil. Trans, for 1811, pp. 36, 211; or Journal, vol. KXIX, p. 359.]
found
ACTION OF POISONS ON THE ANIMAL SYSTEM. 265
\
found acting slowly and feebly, after the functions of the
brain had entirely ceased. In the rabbit, the effects of the
arsenic on the stomach and intestines were usually less than
in carnivorous animals.
The action of arsenic on the system is less simple than that Actionof arse-
of the majority of vegetable poisons. As it acts on different Tie Jess simple
organs, it occasions different orders of symptoms ; and as the most vegetable
affection of one or another organ predominates, so there is some poisons.
variety in the symptoms produced even in individual aninaals
of the-same species.
In animals killed by arsenic the blood is usually found fluid Appearances
in the heart and vessels after death ; but otherwise all the */ter death.
morbid appearances met with on dissection are confined to the
stomach and intestines. As this is the case, and as the aftec-
tion of these organs occasions remarkable symptoms, it may
be right to mention the result of my observations on this
subject.
In many cases where death takes place, there is only a very State of the
slight degree of inflammation of the alimentary canal ;. in alimentary ca-
other cases the inflammation is considerable. It generally ae
begins very soon after the poison is administered, and appears
greater or less, according to the time which elapses before the
animal dies. Under the same circumstances, it is less in gra-
minivorous, than in carnivorous animals. The inflammation is
greatest in the stomach and intestines; but it usually extends
also over the whole intestine. I have never observed inflam-
mation of the oesophagus. The inflammation is greater in
degree, and more speedy in taking place, when arsenic is
applied to a wound, ‘than when it is taken into the stomach.
The inflamed parts are in general universally red, at other
times they are red only in spots. The principal vessels leading
to the stomach and intestines are turgid with blood; but the
inflammation is usually confined to the mucous membrane of
these viscera, which assumes a florid red colour, becomes soft
and pulpy, and is separable without much difficulty from the
cellular coat, which has its natural appearance. In some in-
stances there are small spots of extravasated blood on the inner
surface of the mucous membrane, or between it and the
cellular coat, and this occurs independently of vomiting. I
have néver, in any of my experiments, found ulceration or
sloughing
266 ACTION OF POISONS ON THE ANIMAL SYSTEM.
sloughing of the stomach or intestine; but if the animal sur-
vives for a certain length of time after the inflammation has
begun, it is reasonable to conclude, that it may terminate in
one or other of these ways,
Sloughing sel- 1 am disposed to believe, that sloughing is very seldom, if
pose aeaki a ever, the direct consequence of the application of arsenic to the
sequence of the Stomach or intestines. Arsenic applied toan ulcer’ will occa-
ee me sion a slough ; butits action in doing this is very slow. When
stomach or in- | have applied the white oxide of arsenic toa wound, though
testines; .- the animal has sometimes lived three or four hours afterward,
and though violent inflammation has taken place in the sto-
mach and intestines, I have never seen any preternatural ap-
pearance in the part to which it was applied, excepta slight
effusion of serum into the cellular membrane. Arsenic speedily
produces a very copious secretion of mucus and watery fluid
from the stomach and intestines, which separates it from actual
contact with the inner surface of these organs, even though
taken in Jarge quantity and in substance ; and in animals which
are capable of vomiting, by much the greater part is rejected
from the stomach very soon after it has been taken in, Hence
though a few particles of arsenic are sometimes found en-
tangled in the mucus, or in the coagulaum of extravasated
blood, and adhering to the inner surface of the stomach, I have
never scen it in such a quantity as might be supposed capable
Bupsieted of producing a slough. In one instance, where a dog had
sloughs from swallowed a large quantity of arsenic in substance, a brown
ak pena spot, about an inch in diameter, was observed after death on
" the inner surface of the cardiac extremity of the stomach,
having so much of the appearance of a slough that at first I
had no doubt of its being so; but on examination this proved
to be only a thin layer of dark-coloured coagulum of blood,
adhering very firmly to the surface of the mucous meme
brane, and having a few particles of arsenic entangled in it.
On removing this the mucous membrane still appeared of a
dark colour ; but this was also found to arise from a thin
layer of coagulum of blood between it and the cellular coat.
The mucous membrane itself was inflamed ; but otherwise in
a natural state. I have observed a similar appearance, but oc-
cupying a less extent of surface, several times. In the Hune
terian Museum there is ahuman stomach, which was preserved
to show
>
ACTION OF POISONS ON THE ANIMAL SYSTEM. 267
to show what was considered as a slough produced by the
action of arsenic. On examining this preparation, I found that
the dark-coloured spot, which had been supposed to be a slough,
was precisely of the same nature with that just described.
Although the affection of the stomach and intestines from The affection
arsenic is not the cause of death under ordinary circumstances, ee gcse ee
it is reasonable to conclude, that it may be so in some in- from arsenic
stances, if the animal survives the effects produced on the neta i
organs more immediately necessary to life. Mr. Henry,
Earle informed me of an instance, in which this appeared to ba
the case. A woman in St. Bartholomew’s hospital, who
had taken arsenic, recovered of the immediate symptoms, but
died at the end of four or five days. On examinationafter
death, extensive ulcerations were found of the anton llc
brane of the stomach and intestines, which we can hardly
doubt to have been the cause of death.
It is an important matter of inquiry, as connected with judi- Important ju-
cial medicine, how far may the examination of the body, after ae Pipa de
death, enable us to decide, whether an animal has died of the possible to as-
effects of arsenic? On this subject, however, I have only a eis eee
few remarks to make. from examina-
The inflammation from arsenic, occupying in general the fo8 a iene
whole of the stomach and intestine, is more extensive than that By
from any other poison with which I arn acquainted. It does
not affect the pharynx or cesophagus, and this circumstance
distinguishes it from the inflammation which is occasioned by
the actual contact of irritating applications.
But Jittle in general is to be learnt from the examination of
the contents of the stomach after death. When arsenic has
been taken in substance, small particles of it are frequently
found entangled in the mucus, or -in the extravasated blood;
but. where this was not the case, I have never known, inan
animal. that was capable of vomiting, that arsenic could be
detected in the contents of the stomach after death, though
‘examined by the most accurate chemical tests. As some sub-
stances when taken internally are separated from the blood
very soon afterward with the urine, I thought it probable, that
arsenic might be separated with the urine also ; but Mr. Brande
(to whom I am indebted for. assistance on this, as well as on
ms many
t®
>)
ie
Manufacture
of Prussian
blue offensive,
One source ob-
Viated.
Another from
the potash,
Apparatus to
obviate this.
Described.
APPARATUS FOR PRUSSIAN BLUE.
many other occasions) could never detect the smallest trace of
arsenic in it,
(To le concluded in our next.)
IV.
Description of an Apparatus Ly means of which all bad Smell
may be avoided in manufacturing Prussian Blue: by Mr.
D’ARCET*,
WHE manufactures of Prussian blue diffuse to a distance
a] two kinds of bad smell. The first, that produced from the
combustion of animal matter, is easily avoided by covering the
crucible with a dome, at the summit of which is the chimney
of the furnace, and setting fire te the vapours emitted from the
crucible, as soon as they are hot enough to burn.
The second source of the bad smell is found in the use of
the potash of the shops, which contains more or less sulphate
of potash. When the mixture of blood and potash is calcined,
the temperature is high enough for the sulphate to be decom-
posed and converted into sulphuret, by means of the animal
charcoal mingled with it: whence it follows, that. the Prussic
liquid always contains hydrosulphuret of potash in solution ;
and that, when this liquor is mixed with the solution of alum
and sulphate of iron, a large quantity of sulphuretted hidro-
gen gas is evolved, which is extremely fetid, and diffuses itself
to a distance, tarnishing plate and spoiling meat, that is within
its sphere of action.
By means of the apparatus about to be described, these in-
conveniences may be avoided, and the sulphuretted hidrogen
gas evolved on the mixture of the two liquids may even be
turned to advantage.
Pl. VII, fig. 1, a, is atub of white wood, well hooped, and
firmly supported by two pieces of wood, that raise it from the
ground, and preserve the bottom from rotting.
b is a hemisphere of thin copper, of the same diameter as
the tub, and serving as a cover toit. It fits into it up to the
* Ann. de Chim, vol. LEXXII, p. 165¢
rina
a
APPARATUS FOR PRUSSIAN BLUE. 569
rim that appears in the figure. Before the cover is put on, the
edge of the tub and the lower face of the rim are to be coated
with potter’s clay well diluted, which will render the juncture
perfect. ;
¢ is a copper tubulure, through which the stem of the beater:
h is to be passed, before the cover is put on the tub,
h elevation of the beater. Toward the upper end of the
stem is seen a piece of skin fastened to it. When the beater
is placed in the tub, and the stem passes out through the cover,
the lower part of the skin is fastened to the rim of the tubu-
lure, and thus the communication with the air is prevented,
without prejudice to the movement of the beater. The skin
used should be soaked in oil, that it may not be injured by the
liquids put into the tub.
£ plan of the foot of the beater.
~ d fannel through which the different solutions are poured
into the tub.
1a wooden plug used to stop the neck of the funnel.
4 acock, or spigot and faucet, by which the Prussian blue is
drawn off from the tub, after the solutions have been well
mixed in it.
m a small tub, sunk into the ground, into which the result
of the mixture runs. As the liquid Prussian blue runs into
this, it is dipped out with a ladle into a bucket, to be carried to
the casks, in which it is to be washed with a large quantity of
water.
ea curved tube fixed to the dome.
fatube of the same diameter fixed in the ground. The
dotted lines, terminating at m, point out the situation of this
tube, which is placed parallel with the surface of the ground,
and terminates in the ash-pit, near the grate of the furnace
_ where the prussiate of potash is prepared. When the cover is
put down on the tub, the tube e should enter into the tube /
and the juncture is to be luted with a little potter’s clay.
‘Hig. 2 represents the apparatus put together, and ready for Mode of using
use. When the solutions are prepared, the door of the ash-pit, **
in which the tube terminates, is to be shut close; the plug / is
to be taken out of the funnel, and the solution of alum and
sulphate of iron poured in, A workman mounts a little stool,
takes hold of the stem of the beater h, and begins to agitate the
liquor
270 APPARATUS FOR FPRUSSIAN BLUE.
Jiquor in the tub, Two others pour the prussic liquor gently
into the funnel d, and the workman who holds the beater moves
itin all directions, that the liquors may be intimately mixed. A
little of the mixture is drawn off occasionally by the cock 3,
filtered through blotting paper, and examined, to find whether
a sufficient quantity of prussiate of potash have been poured in:
if not, more is added ; and, when it has reached the point of
saturation, no farther addition is to be made, but the stirring
of the mixture with the beater is to be continued about ten
minutes.
The ash-pit of the farnace being closed, the draught of the fire
causes the outer air to enter through the tube of the funnel d;
this air mixes. with the gasses extricated from the mixture, and
the whole is conveyed through the tube e m underneath the
grate of the furnace, where the sulphuretted hidrogen takes
fire, loses thus its offensive smell, and serves also to keep up the
heat of the crucible.
When the stirring of the mixture is finished, the tub may
be emptied by the cock, and a new mixture immediately com-
menced.
The cover of the tub need not be taken off, except when
the apparatus wants repair. When it is left some time out of
use, the tub should be kept full of water, and this water may
be employed afterward for lixiviating the residuum of the calci-
nation of the blood and potash.
It has been The apparatus here described and figured I have caused to be
et with ftted up at the paper-hanging manvfactory of the brothers Jac-
quemart. It has succeeded completely, no inconvenience has
been found in its use, and it has entirely freed the work-shops
and neighbourhood from the bad smell diffused by mixing the
prussic liquor, and the solution of alum and sulphate of iron.
Note of the French Editors.
A similar ap- An apparatus of this kind, but by no means so well con-
Paratus atano- structed, has also been employed with success for several years
ther manufac- . ‘ ; d
tory in a manufactory of Prussian blue in St. Nicholas-street.
a ,
METHOD OF SAWING CAST IRON,
©
ae!
ps
Vs
Extract from a Letter addressed to Mr. v’Arcet bly Mr. Du-
FauD, Director of the Iron Works at Montalaire, near Creil*.
SIR,
HAVE undertaken, with the greatest pleasure, the expe- Sawing heated
riments on sawing hot cast iron, that you recommended to aa wera
me: I have followed your instructions ; my trials have been
attended with the most complete success, and I hasten to give
you an account of them.
These experiments were the more interesting to me, as I
have since applied them to practical purposes.
My first trial was made with the support of a grate, 108 mil. Experiment.
{425 in.] thick. This piece of cast iron was heated in a forge
fire with coal : and as soon as it had acquired a sufficient de-
gree of incandescence [this is the French term] it was placed
on an anvil, and I sawed it with a common carpenter’s saw,
without any difficulty, and without any injury to the saw,
which I dipped immediately into cold water. The carpenter
continued to work with the same saw, without having any
occasion to repair it.
In this my first trial a little accident occurred. The end of The iron
the iron I was sawing off not being supported, it broke, when eka, ane
20 or 25 m. (about a line) remained to be cut through ; but done, for want
this slight defect I immediately removed with the saw. Con- ela “a
vinced of the ease with which a common saw would cut hot
cast iron, I afterward applied it to the demands of the iron-
works,
I had occasion to shorten a pivot of 135 m. [5°3 in.] in dia- second experi-
meter ; but, afraid of its breaking if I cut it cold, an operation ment.
besides very tedious and uncertain, unless executed in a lathe,
I had resolved to cast another, when the experiment I have
just mentioned determined me to saw it.
Having marked the place of section with red lead, I placed
the pivot in a reverberatory furnace ; and when I thovght it
sufficiently hot, I had it taken out of the furnace, and placed
on an iron support, so that the two ends had equal bearings.
? Ann, de Chim, vol, LAXXII, p. 218.
In
eS)
“I
ee)
Third experi-
ment,
General re-
marks,
The practice
METHOD OF SAWING CAST IRON.
‘Tn four minutes, with two saws, which I used and cooled alter-
nately, the piece was cut off, tothe great astonishment of my
workmen, who found the saws unhurt.
The same day I performed a still more difficult operation.
I had an anvil, which I was about to cast afresh, because it was
41 m. [1°6 in.] too thick, so that it could not be placed in its
bed.
I marked the place of the saw kerf with red lead. The
two cuts to be made were 217 m.[8°5 in.] long, by 189 m.
[7'4 in.] high ; and the thinness of the piece to be cut off re-
quired precision, This anvil was heated in a reverberatory
furnace, in the same manner as the pivot; and, when suffi-
ciently hot, two workmen took hold of it with a strong pair of
tongs, and Jaid it on a block of cast iron. It was cut with
much ease and precision by the same saws that had been used
in the preceding instance.
In the course of these experiments I remarked,
1, That hot cast iron may be sawed as easily, and in the
same space of time, as dry wood.
2, That, to diminish the resistance, the saw should be set
fine.
3, That iron heated in a furnace saws more easily than if
heated in a forge: and the reason is simple ; in a furnace it is
heated equally throughout, while in a forge the part near the
tewel is almost in a state of fusion, while that opposite to at is
scarcely red-hot.
4, That the iron must not be made too hot ; for, if its surface
be too near a state of fusion, the saw will be clogged, and the
process will not go on well.
5, That the saw should be moved very quickly, because then
it will be less heated, make its way better, andthe cut will be
more clean and exact.
G6, Lastly, that the iron should be so placed as to have a firm
bearing every where, except where the saw is to pass, otherwise
it is liable to break before the cutting is finished.
These, Sir, are the whole of my experiments and observa-
tions ; and I shall be well pleased if they answer your views.
It is the more to be wished, that this method of cutting cast
may be of ex- iron should be rendered as public as possible, as it may be hap-
pily
METHOD OF SAWING GAST IRON. 973
pily applied in many arts. I thank you much for having sug- tensive use.
gested it to me, for I shall find frequent occasions for it.
Note by Mr. p’Arcer.
Several years ago Mr. Pictet observed a workman saw a Practised some
cast iron pipe in the workshop of Mr. Paul, of Geneva. He haa cM at
had lately occasion to mention this to Mr. Thenard, who after- ‘
ward communicated it to Mr. Mollard. Mr. Mollard, struck
with the uses to which it might be applied, tried it at the Con- Experiments
servatory of Arts and Trades on pieces of cast iron 7 cent, at Paris.
[2°75 in.] square, and on plates of different thicknesses.
Mr. Mollard used a common saw, and succeeded. perfectly
with these various pieces, without injuring its teeth. He ob-
served, that the iron should be heated on!y toa cherry red ; and Instructions.
that it should be cut briskly, using the whole length of the
saw. Mr. Mollard afterward found, that this process was raown to
Known to a workman of Mr. Voyenne, who practised it in others,
fitting the cast iron plates used for making stoves. It is pro-
bable, that this simple operation may be known in other work-
shops ; but it is lost, as it were, since persons of distinction in
the arts are generally ignorant of it.
We see, that the experiments mentioned in Mr. Dufaud’s The practica-
letter confirm the account of Mr. Pictet, and the trials of Mr, bility demon-
Mollard : of course there remains no doubt of the possibility ars
of cutting cast iron when hot, or of the utility of the process,
We conceive it would be practicable to employ it in the fa- 17.05 t9 which
brication of iron cannons, for cutting off the cap of the piece, it may be ap-
and even for removing the square piece left at the extremity of Plied =
the button, which serves for mounting it on the boring machine. ron x
Perhaps advantage might be taken of the red heat, which the
cannon retains long after it is cast, for sawing off the cap in the
mould itself, its upper part only being removed.
The same process would certainly furnish an easy and ready ianeaviite-up
method of cutting a cannon to pieces, and thus rendering it remelting
unserviceabie ; or facilitate its melting in the reverberatory them,
furnace, when required to be cast afresh, Perhaps it might be
employed also to ascertain the different ranges of a piece of ..9 ascertains
cannon, shortened by little and little. It seems to us, the ing their
knowledge of a practice applicable to so many purposes of the bine Ais,
arts cannot be too generally made known.
Vou. XXXIII, No. 154.—Decemser, 1812, T Vi.
274
Sugar had not
been chemi-
cally com-
pounded.
Supposition
that it might
he formed
from starch,
and from gum,
Said to have
been done:
but by no one
before Kir-
choff.
Component
partsof starch,
Starch reu@
SUGAR OF STARCH.
VI.
On the liquid Sugar of Starch, and the transmutation of sweet
Substances into fermentable Sugar : by Mr. VocEt. Abridged
by Mr. Bouitton-Lacrance*,
O chemist has hitherto been able to form sugar by che-
mical agents. It is true, that Fourcroy and some others
supposed, that at some time or other we should perhaps effect
the conversion of starch into sugar, as the component parts
of these two substances come infinitely near each other.
** Starch,” says Fourcroy, ‘‘ announces itself as a little less
carbonated than gum : we may say, that it comes very near to
saccharine matter ; and we shall see hereafter, that it appears
in fact capable of forming it by a particular alteration of its
own substancef.”
Under the head gum, the same chemist expresses himself
as follows. ‘ It is not improbabie, that art may effect the
conversion of gums into saccharine matter ; and already I have
several times remarked, that an aqueous solution of gum,
through which oximuriatic gas is passed, acquires a saccharine
taste, mixed with a strong bitterness. This view of the subject,
at present quite novel, will lead to many researches, and to
useful results.”
It is even pretended, that several authors say they have ef-
fected this transmutation of fecula into saccharine matter : but
how is it possible, that they should have succeeded, and been
silent on a fact of such importance ?
On looking over what has been published by natural philoso-
phers, it appears incontestable, that it was reserved for Mr,
Kirchoft, of the imperial academy of Petersburgh, to convert
starch into gummy matter, and this into saccharine mattert.
His
* Ann, de Chim, vol. LXXXII, p. 148,
+ According to Messrs, Gay-Lussac and Thenard, starch is composed
of
Carbon éisis's | sarees seis 43°55
Oxigen:+++e« evecese 49°68
Hidrogen+ +++ s+e+++ 6°77
16°000
¢ Mr, Bouillon Iaagrange has already found means of rendetin
SUGAR OF STARCH: 275
His discovery, which - opens a new ¢areer to vegetable His discovery
analysis, and may lead to interesting results, has induced Mr. heer Ys by
Vogel to pursue these new facts. His first experiments, some ore
particulars of which he has given in the Journal de Physique,
differ scarcely in any thing from those of Mr. Kirchoff, except
in his observing, that part of the saccharine matter is formed
in the course of two hours boiling, and that the proportion of
two hundredths of sulphuric acid produces more than that of
one hundredth, the quantity mentioned by the chemist, of
Petersburgh.
Since that time Mr. Vogel has followed up his experiments
with more care, in order to acquire an intimate knowledge of
the saccharine matter, and the mode of its formation.
‘To remove every idea of the saccharine matter being the Not ready
result of simple extraction; a matter that, having escaped eae
fermentation, was eoncliitel by the starch ; he washed the
starch with a stream of cold water, before he made use of it,
When well dried and reduced to powder, he mixed 2 kil, Method of
[Albs. 65 oz. avoird.] with 8 kil. of Seine water, acidulated prndennes
with 40 gr. [0°02 of the weight of the starch] of sulphuric
acid at 56° [1631].
He then boiled the mixture in a silver basin for thirty-six
hours. There is no danger of its burning, except during the
first hour, when it must be kept constantly stirring with a
broad wooden spatula. After that time the mixture grows
much more fluid, and requires only to be stirred occasionally.
It is essential to keep up the quantity of water, by adding
fresh as it evaporates.
After this boiling, it is to be clarified when cold by means of @larification.
charcoal and chalk, and the whole is to be filtered through
flannel. :
The liquid having been evaporated nearly to asirupy con- Evaporation.
sistence, it must be left to cool, that more of the sulphate of
lime may fall down ; after which the clear liquid is to be de-
canted off, and the evaporation finished.
The sugar thus obtained with two hundredths of sulphuric A Sadar gy
Acid in a silver basin was much more saccharine, afd less tinned copper.
high coloured, than that made in a basin of tinned copper.
starch soluble in cold water by a slight torrefaction, and thus assimi- dered soluble
lating it to mucilages. See Builetin de Pharm., tom. iti, p, 395. in cold water,
T2 The
276
Lead may be
used.
Quantity of
sugar pro-
duced.
4
Many sweet
substances
e€entain no
sugar.
2
Sugar from
starch fer-
mented,
giving out
SUGAR OF STARCH.
In general the latter cannot be used for the purpose, the tin
being strongly attacked by the long continued boiling. A
leaden vessel has been substituted for it with success.
The 2 kil. boiled with two hundredths of sulphuric acid
yielded, in several comparative experiments, sometimes a little
less, sometimes a little more than 2 kil. of sirup at 33° of the
areometer [1295]; so from a mean of them we may con-
clude, without any material errour, that starch yields its own
weight of sirap*.
As many substances havea decidedly sweet taste, for instance
sugar of milk, the sweet matter in liquorice, the sweet prin-
ciple of Scheele (formed during the action of fat oils on litharge
in making plasters), without however, containing an atom of
sugar, Mr. Vogel thought it necessary to ascertain, in the first
place, whether the sweet liquor from starch contained real sugar.
For this purpose he mixed some yeast with 200 gr. [3089
-gxs.] of sirap of starch in warm water, and put the whole into
a phial, communicating with the pneumatic apparatus, by
means of a sigmoid tube.
‘Fermentation soon took place, witha very brisk extrication
carbonte acid, ‘of carbonic acid gas.
and yielding
alcohol.
Sirup of starch
contains gum.
Result of its
evaporation.
May be em-
ployed in
pharmacy ;
but itis deli-
quescent.
Fecula of po-
tatoes equaliy
yields sugar.
‘Phe 200 gr. of sirup yielded by the fermentation upwards of
5 lit. [near 6 quarts} of carbonic acid gas ; and a notable quan-
tity of alcohol was obtained by distillation.
I¢ is certain, that all sirup of starch contains more or less
gum, the quantity of which variesextremely, according to the
time of boiling, and the weight of the acid employed. _
The most saccharine sirup evaporated slowly in a stove, and
dried in tin moulds, afforded a perfectly transparent elastic
substance, in every respect similar to the paste of jujubes.
The author has no doubt, that apothecaries may avail them-
selves of the sirup of starch, for all this kind of gummy saccha-
rine medicaments, particularly those that may remain in a soft
state; for the sirup of starch, thus reduced to a solid state, at-
tracts moisture from the air.
Mr. Vogel substituted the fecula of potatoes for starch, and
equally obtained a very saccharine gummy sirup.
’
* Starch boiled eight hours with four hundredths of sulphuric acid
yielded thesame results.
The
f
SUGAR OF STARCH,
277
‘The gum was separated by boiling the sirup in a close vessel
with alcobol at 30° [0'868.]
The matter on which the alcohol had no action, and which The gum
was found in the most perfect sirup to the quantity of two
tenths, was very viscous, Being dried and powdered, it exhi- gmitor to gum
bited al] the characters of gum arabic, namely, its solubility arabic,
in cold water, forming a thick mucilage, insoluble in alcohol.
The only character, that appears to distinguish this matter but does not
from gum arabic, is its not forming mucous acid with nitric yield macons
acid. acid,
It has been asserted, however, that. the gummy matter pre- The eum said
cipitated from sirup of starch isa compound of starch, water, to be a com-
and sulphuric acid. pound,
To satisfy himself on this head, Mr. Vogel poured a small but this dis-
portion of alcoho! into sirup of starch. The precipitate first Proved.
_ formed was composed of sulphate of lime and gum. When
this was separated, he poured more alcohol into the sirup that
had been decanted from it. The second precipitate was
gummy matter, unmixed with sulphate: its solution in water
was no longer rendered turbid by muriate of barytes.
The author, however, was not content with this experiment ; Farther confir-
for it might be objected to him, that the sulphuric acid, being pee oo > ie
chemically combined with the gum, would not quit it to unite sulphuric acid.
with the barytes. He dissolved this gum therefore in barytes
water evaporated to dryness, and gave the mass a strong red
heat in a platina crucible: thus the sulphric acid should
have been set free, and no doubt would have seized on the
barytes. Besides, this sulphate would have been decomposed
by the carbon of the gum, and converted intoa sulphuret : but
muriatic acid poured on the calcined matter extricated nothing
but carbonic acid gas, and not an atom of sulphuretted hidrogen
gas that could be rendered sensible by paper impregnated with
acetate of lead.
Besides, the gum distilled on an open firedid not give out any
sujphurous acid, or sulphuretted hidrogen gas.
It is not therefore a hydrate of starch combined with sul- pypotheses
phurie acid ; which affords us a fresh proof, that we must take tly ocr eal
_ care not to frame hypotheses before we consult experiment.
He made the same trials with the sirup deprived of gum by No
alcohol, which did not precipitate the muriate of barytes ; but
he
sulphuric
278 SUGAR OF STARCH.
acid in the si. he could not discover in it the least trace of combined sulphuric
rup. acid.
Action ofacids hese experiments could not fail gradually to lead to an exami-
on other sub-» nation of the action of acids diluted with water on some other sub-
stances tried. stances. Sugar of milk first drew his attention; and with the
greater reason, as we have already announced this substance to
become more soluble in water after it has been treated with
acid.
Sugar of milk Mr. Vogel boiled 100 gr. [1545 grs.] of sugarof milk with
treated with 4090 gr. of water, and 2 gr. of sulphuric acid at 56° [1°631],
sulphuric acid, : j
for three hours, adding more water as it evaporated. After hav-
ing saturated the excess of acid by carbenate of lime, he filtered.
_ The liquid, though clear, was slightly coloured. Evaporated
slowly ina stove, a thick brownish sirup remained, which con-
creted into a crystalline mass at the expiration of a few days.
PUN eles This matter resembling soft sugar has a much mote saccharine -
product, taste than the most concentrated aqueous solution of sugar of
milk, From this extremely saccharine iaste the author was led
to suspect, that a real sugar had been formed, capable of giving
rise to the alcoholic fermentation.
Fermented, In fact this product mixed with yeast diluted with water was
scarcely placed in favourable circumstances for the alcoholic fer-.
mentation, before it commenced in a very brisk manner;
though sugar of milk never ferments, as is well known to all-
chemists, and has been recently placed beyond all doubt by the .
numerous experiments of Mr. Bucholzt.
and yielded This fermented liquor yielded a considerable quantity of
rele alcohol. On varying the proportions of sulphuric acid tothree, .
four, and even five hundredths, very saccharine crystals, that
ran into fermentation with extreme facility, were constantly ob-
tained, particularly with five hundredths of acid.
Nitric acid has With two or with four hundredths of nitric acid the sugar of
not thesame miJk could not be converted into a fermentable sugar.
effect. ne ’
Mutiaticaciad _Lhree grammes [46°3 grs.] of muriatic acid converted the
has. sugar of milk into a very saccharine sirup capable of the alco-
Acetic acidhas holic fermentation ; while 2 gr. [30°89 grs.] of radical vinegar
pms made no alteration i in the sugar of milk.
* See Delamétherie’s Journul de Physique, July, 1811.
+ See Delamétherie’s Journ, de Physique, for December, 1811.
All
SUGAR OF STARCH. é 979
All these sirups reduced to the crystalline state differ from The supsiance
sugar of milk, not only in being susceptible of the alcoholic gia ia
. eran, A . ircer
fermentation, but also in being very soluble in alcohol, a property supun ee em
that sugar of milk does not possess. Evaporated to dryness by
a gentle fire, a white, granular, and extremely saccharine mass
is the result.
qt remains to explain the manner in which sulphuric acid Theory difi.
acts on starch and sugar of milk, to take from them the principie ut.
that masks the saccharine substance, or to convert them into fer-
mentable saccharine matters. The author confesses, that it is
difficult, and out of his power, to givea clear and plausible
theory of this metamorphosis ; and, if he risk some notions on
this subject, it will be with much reserve.
Many are disposed to adopt the opinion, that sugar exists ready Supposition,
formed in ‘starch, andthat the sulphuric acid only dissolves or that the sugar
destroys the principle that holds it enchained. a rent ae
It is obvious, that this reasoning is in a considerable degree Opjections.
vague ; and besides, that it is founded on no experiment, direct
or indirect. In this hypothesis too we must imagine a com-
pound altogether new, sugar combined with a substance that
renders it insoluble in cold water ; and sugar has never yet pre-
sented us with such a compound.
Others have supposed, that heat alone is capable of effecting Shippuuiian
this conversion of fecula into saccharine matter ; a fact which, that the con-
aye : st +. Version is ef-
if it were confirmed, might throw fresh light on the saccharine ¢7r by, best
fermentation of Fourcroy. alone.
Accordingly starch has been boiled with water four days in yi gis.
succession, till it became extremely fluid. The filtered liquor proved.
was evaporated, and the result was a thick mucilage, very bitter,
without the least taste of sugar. The starch remaining on the
filter resisted the action of boiling water, and exhibited a very
hard horny matter. .
It remains to be examined, therefore, whether the sulphuric Is the acid, or
acid, or the starch itself, be decomposed. choneal
To judge by the letter from Petersburgh, the Russian chemists 7) op sans
seem to suppose, that a decomposition of the sulphuric acid seem to think
takes place the former.
To account for these phenomena, we should operate in close PRIN
vessels. Accordingly, the author introduced into a tubulated ““Pement
receiver
280
with sugar of
milk,
The sugar of
milk decom-
posed, not the
acid.
Experiment
repeated in
close vessels,
Water appa-
rently formed,
SUGAR OF STARCH.
receiver a hundred grammes of sugar of milk, four of sulphuric
acid, and four hundred of water. To the neck of the retort
was adapted a tubulated receiver, from which proceeded a sig-
moid tube, opening under a jar filled with water.
After boiling for three hours, no gas had come over, except
the air contained in the vessels. A piece of blue paper intro-
duced into the neck of the retort was not reddened. The wa-
ter that had passed into the receiver was without taste, did not
redden litmus paper, had no smell of sulphurous acid, and did
not precipitate lime-water, muriate of barytes, or acetate of lead;
consequently it contained no sulpburous, sulphuric, acetic, or
carbonic acid ; in short, it was nothing but pure water.
Barytes-water traversed by the bubbles, extricated during the
process, was not rendered turbid in the least, and the gas that
had passed into the jars was nothing but the air of the vessels.
It is evident, that the sulphuric acid had not undergone the
slightest decomposition : nevertheless, the sugar of milk was
decomposed ; it had a much more saccharine taste, and after
saturation with chalk it fermented very readily with yeast.
Tt was necessary, therefore, to examine the decomposing
action of the sulphuric acid on the substances in question.
For this purpose the same experiment was begun afresh in close
vessels, with i100 grs.of sugar of milk, 400 grs. of water, and
4 grs. of sulphuric acid. During the process no gas was evolved,
as in the preceding experiment. ;
The liquid was then concentrated in a dish accurately
weighed, after having added 5 grs. of potash to saturate the
acid,
The | mass thus evaporated to dryness should have weighed
109 ors. in consequence of the 100 grs. of sugar of milk, 4
gts. of sulphuric acid, and 5 grs. of potash employed; but it
weighed only 98 grs. consequently there was a loss of 11 gts.
This experiment was repeated twice more, and there was still
a loss of 9 or 11 grs. giving a mean of 10 gts.
This loss is too great to be ascribed to any errour in the
weighing, which was conducted with the greatest care.
Hence we must conclude, tbat this diminution of weight
is occasioned by a quantity of water formed at the expense
of the sugar of milk; and this with the more reason, as no
gas,
ee
.
:
SUGAR OF STARCH. 281
gas, no acid, and no other volatile substance, was extricated
during the boiling.
All these experiments with the sugar of milk were equally starch aford-
repeated with starch, except that a much larger quantity of wa- ed similar re.
ter was added to prevent it from burning. The results were ak
the same as those obtained with sugar of milk.
Conclusions.
From all that has been said, it follows :
le That starch and the fecula of potatoes, boiled with water General con-
acidulated with sulphuric acid, are converted into a liquid sac- clusions,
charine matter, the quantity of which corresponds with the
weight of the starch employed. ;
2. That this saccharine matter is susceptible of the alcoholic
fermentation.
3. That the sirup of starch is composed of gummy matter
and saccharine matter in variable proportions.
4, That the sirup evaporated slowly in a stove exhibits an
elastic substance, perfectly transparent.
5. That the gummy matter exhibits all the characters of a
true gum, except that of forming mucous acid by means of the
nitric.
6. That neither this gum, nor the saccharine matter, holds
sulphuric acid in combination.
7. That the heat of boiling water alone is insufficient to con-
vert starch into saccharine matter, as nothing is obtained but
a bitter matter, and a horny substance insoluble in boiling water.
8. That sugar of milk treated with two, three, four, or five
hundredths of sulphuric acid is converted into confused crys-
tals, which have an extremely saccharine taste, and are suscep-
tible of the alcoholic fermentation.
g. That this saccharine matter does not contain any sul-
pharic acid in combination.
10, That the muriatic acid effects the same changes in sugar
of milk.
11. That neither the nitric nor acetic acid converts sugar of
milk into fermentable sugar.
12. That sugar of milk thus converted into fermentable
sugar becomes very soluble in alcohol,
; 13, That
4
282
Deliquescence
reducible to
general prin-
ciples,
»
Owing to the
attraction of
a substance for
water.
ON THE DELIQUESCENCE @F BODIES.
13. That sulphuric acid is not decomposed in its action on
starch and sugar of milk: and that, from the facts mentioned,
it ismuch more probable, that the acid takes from these sub-
stances oxigen and hidrogen in the proportions necessary to
form water.
VII.
Abstract of a Paper on the Deliquescence of Bodies ; 3 by Mr.
Gay-Lussac*.
N the 17th of May [1812] I communicated to the So-
ciety of Arcueil some observations on the property that
bodies have of attracting the moisture of the air, and which is
more particularly designated in chemistry by the name of
deliquescence. This property, hitherto badly analysed, may
be reduced to general principles, by which we may easily
ascertain what bodies possess it, the variations it undergoes ac-
cording to the temperature, and the degree of the hygrometer
at which it begins to manifest itself.
As the deliquescence of a body is owing to its affinity for
water, and as the effect of this affinity isto diminish to a i:
tain degree the elastic force of the vapour contained in a deter-
minate volume of air, it is very essential, both for knowing
Mode of ascer- Whether deliquescence can take place, and for obtaining com-
taining it.
Exists where it
had not been
suspected.
Temperature
to be attended
ta,
Method of
finding the de-
parable results, to place each body in an atmosphere completely
saturated with moisture. Thus we find, that muriate of soda,
sugar, &c., are very deliquescent; and that even nitre, and
many other substances, in which this property had not been ob-
served, possess it more or less.
We cannot thus ascertain the degree in which a substance
is deliquescent : but, to accomplish this, we must first observe,
that, the deliquescence of a substance depending on its affinity
for water, and this affinity itself being strikingly modified by
heat, it is necessary to consider each temperature in par-
ticular.
Suppose then a given substance, solid or liquid; and we
wish to know its degree of deliquescence in an air saturated
* Ann, de Chim, vol. LXXXU, p. 171.
» with
a ia a ee PS
ON THE DELIQUESCENCE OF BODIES. 933
K
with moisture at 150 of the centigrade thermometer [59° F.]. gree in which
Af it be solid, first make a saturated solution of it in water at @ substance Is
15° [59° F.], and boil the solution®. If it boil at 100° [212° F.] “°"a8sscents
the boiling pointof pure water, the substance is not deliques-
‘cent: but if it do not boil at so low a degree, it is more deli-
_quescent in proportion as the boiling point rises higher above
“100°. Thus muriate of soda will be very deliquescent in air
saturated with moisture, for its solution in water at 15° [59° F.]
will not boil below 107°4°. [225°32° F.]. Nitre, too, will be
deliqueseent, but much less than the preceding salt, as its solu-
tion at 15° boils at 101°4° [214°52 F.].
Experiment here perfectly agrees with the theory ; but to The theory
. “MAN ghey si. - agrees with
have agood view of the deliquescence of nitre, and of all sub- experiment.
stances like it feebly deliquescent, they must be taken in small -pyeatment of
separate parcels : in this state they will be found to dissolve slightly deli-
completely, while large crystals would only be covered with a a stile
liquid stratum, or would dissolve very slowly.
‘It is easy now to perceive how important it is to attend to Importance of
the temperature ; for as heat greatly favours the combination of ec tat
salts with water, the boiling point of each solution will vary
according to the temperature at which it is made. Thus nitre, Nitre.
which is but slightly deliquescent at 15°, the saturated solution
of which boils at 101'4, would be greatly so at the temperature
of 100° [212°], as the solution saturated at this temperature
would boil only at 110° or 112° [230° or 233°6° F.]
Acetate of lead and corrosive sublimate do not perceptibly Salts not deli-
tetard the boiling of water; and accordingly they are not at all Tse’
- deliquescent.
In ascertaining the boiling point of saline or acid liquors, I Liquids boil
_ observed a singular phenomenon, that deserves to be made at tower tems
é E : “ , . perature’ in
known, It consists in this, that water, or any other liquid,
* Ichall here observe, that, instead of taking the boiling point of
each liquid, it would be more accurate to take the force of iis va-
pour atthe temperature at which we would determine its degree of
deliquescence, because the elevation of the boiling pointis not pro-
portional to the quantity of salt held in solution. Similar means
should necessarily be employed to know the force with which solids
attract the vapour of water, without any change in their state ensu-
ing, as would take place with lime and salts deprived of their water
of crystallization, This subject is treated at Jength in my original
paper.
ee r does
984 ON THE DELIQ@UESCENCE OF BODIES.
metal, than in does not boil so soon in a glass vessel as in one of metal, unless
te ecauiy filings of iron, copper, or some other metal, powdered charcoal,
some insoluble OF pounded glass, be put into the former. The difference of
powder. temperature for water reaches to 1'3° [2°34° F.], and sometimes
This may af- evenmore, This fact is of the more importance in the gradua-
AS eee" tion of thermometers, as we may observe a similar difference be-
mometers. tween two of these instruments made with equal care, but the
upper points of which were taken one in a glass, the other ina
metallic vessel. It is true, that if care be taken not to immerse
the ball of the thermometer in water, the difference will be less.
No salt lowers TT have found too, that no salt possesses the property of lower-
the boiling J a :
point. ing the boiling point of water, though Mr. Achard has asserted
the contrary. : :
Degree of the Knowing the boiling point of each solution, by means of
AR aa i which we have a measure of the deliquescence of the salt, and
wil! deliquesce of its affinity for water, we may go farther, and ascertain the
ascertainably. Gesree of the hygrometer at which deliguescence begins to
take place. All that is necessary is to place the hygrometer
under a jar moistened with the saline solution, and observe the
degree it will point out at the expiration of a few hours. ‘Thus
“it will be found, that with a solution of muriate of soda, satu-
rated at 15° [59°], the hygrometer will stop at g0°; with a solu-
tion of nitre made at the same temperature, it will stop at 97°>
or thereabout, &c. ;
Muriate of Hence we may conclude, that muriate of soda will not be
ae deliquescent below 90° of the hygrometer, but will begin to be
so at this poist, and become much more deliquescent beyond it.
When a table indicating the degrees of the hygrometer corres-
ponding to the boiling point of a certain number of salts is con-
structed, we may determine the degree of the hygrometer at
which all the others will begin to be deliquescent, as soon as we
know the boiling points of their aqueous solutions. 1 need not
observe, that what is applicable to deliquescent salts is likewise
so to all the solid or liquid bodies that have any affinity for
eulphuric acid Water. On these principles we shall find, that concentrated
absorbs more sulphuric acid is capable of taking more than fifteen times its
Sigil ers weight of water from air completely moist. In setting out
water, from this property of various saline solutions having different
degrees of elasticity at the same temperature, it is easy to deter-
mine with precision for every temperature, and every degree
; 4 of the
al
ON THE UNCOMBINED ALKALI IN ANIMAL FLUIDS. 935
of the hygrometer, the quantity of vapour contained in a given Quantity of
volume of air; which Saussure could not do, notwithstanding V@POUr mir
i : : ascertainable.
his accuracy, on account of the imperfection of his processes.
This method, which I have already pointed out, consists in Process.
taking liquids, from which nothing but water is separated by
heat, and boiling them at very different temperatures; for in-
stance, sulphuric acid more or less diluted ; placing the hygro-
meter underneath jars wetted with each of these liquids ; and
observing the degree at which it stands. On the one hand we
know from my experiments the density of aqueous vapour,
which is to that of airas ten to sixteen; on the other we know
the boiling point, or elasticity of each liquid enclosed under a
jar with the hygrometer : consequently we have all the neces-
sary data for the solution of the problem in question. On this The author
I am at present employed, and I trust it will not prove unin- cP vt
teresting to the science of hygrometry.
VIL.
Remarks on the Correspondence between Dr. Bostock and Dr.
Magcert, on the subject of the uncombined Alkali in the ani-
mal Fluids. In a letter from Grorce Pearson, M.D.
PROS, &c.
To William Nicholson, Esq.
Georpe Street, Hanover Square, Oct, 27, 1812.
SIR,
“WEN your Journal for the present month I read the letter of tptroduction,
Dr. Marcet, addressed to his friend, Dr. Bostock ; in which hie
. . r. at-
he offers the evidence of some experiments to prove, that the ee intor te
potash which exists in the animal fluids is in the state of muriat a rey
(muriate), and ‘‘that the whole of the uncombined alkali is sca ap Sra
soda.” ' by Dr. B.
Itappears, that Dr. Bostock was of opinion, that the sup-
posed uncombined alkali was potash, according to my pro-
visional conclusions, and not soda: but on the representation
of evidence just mentioned, he has changed his opinion, and
therefore has become the vehicle of Dr. Marcet’s letter to the
e public;
286 ON THE UNCOMBINED ALKALI IN ANIMAL FLUIDS.
public ; confiding, as he says, Mr. Editor, that you will
assent, that the evidence offered ‘* must entirely set the question
at rest,”
Statement that One authority declaring the question to be entirely set at
riba d IC rest, and the other affirming that every shadow of doubt is
clusions sup- now removed, alihough { was not ready to believe, as I have
eo Mag had occasion to assert, that more than provisional conclusions
tohave been are likely to be obtained, I at least expected to find some new |
produced. contravening testimony. This I was prepared to acknowledge ;
for, reasoning merely from the known facts, I should have felt
no humiliation if new evidence indicated adverse conclusions—
** Nos non judicis sed indicis personam sustinemus.” (Bacon.)
But on examining the evidence, which it is asserted has pro-
duced conviction, ‘* removed every shadow of doubt,” and
‘set the questiou at rest,” I was unable to perceive any new
facts to alter my former conclusions ; hence I might have
replied merely by a‘counter-ceclaration and reference to my
unanswered experiments and inferences. As, however, this
mode of procedure may be deemed neither decorous to my
opponent, and the testimony produced of respectable personal
authority, nor satisfactory to the public, I respectfully offer the
following brief exposition and remarks.
Rie: awranowes The process, which Dr. Marcet says authorises his confidence
process stated,in former conclusions, was this. ‘The saline matters of the
serum of blood were procured by evaporation to dryness, inci-
neration, dissolution in water, filtration, evaporation again to ©
dryness, dissolution in acetic acid, dissolution again of the desic- |}
cated acetic compound in aleohol ; evaporation of this to dry- —
ness,and fusion. The fused mass, amounting to about four
grains, was divided into four parts, a, b,c, d. |
I, a. 1. “* contained abundance of muriatic acid.”
2. Dissolved in water, and suffered to evaporate sponta-
neously, an efilorescént mass of feathery crystals was afforded.
3. Tartaric acid and oxymuriate of platina manifested the
presence of potash.
Now, I can only infer from’ these experiments, that a mu- ©
tiate was present, probably either of soda, or of potash, or of |
both—that potash was present combined, but with what sub- ;
stance is quite equivocal ; being only a small fractional part ofa —
, grain, it may be united to a doublesalt, although weakly, yet so as
to be —
ON THE UNCOMBINED ALKALI IN ANIMAL FLUIDS.
to be no longer deliquescent. _ It may also be united to mu-
riatic or other acids, especially the sulphuric and carbonic ; but
here is no evidence of soda in a free state, and even only equi.
-vocal evidence of it as united to muriatic acid.
II. The portion b, with sulphuric acid, gave sulphate of soda,
and sulphate of potash.
Here he testimony is equivocal; for the soda may be, and
most likely was, from the decomposition of muriate of soda
by the sulphuric acid. And the sulphate of potash may arise
from the decomposition of potash united to some acid, such as
carbonic, muriatic, &c. united, though weakly, to the other salts,
Hence I perceive no evidence of sodain a free state.
III. The portion c, with nitric acid, afforded rhomboidal crys-
tals, and no prismatical crystals.
I will not repeat the objections I urged to any conclusion
from the form of crystals, especially in such minute portions of
matter as a small part of a grain, set forth so fully in a former
paper ; but it may be right just to remark, that this experi-
ment is inconclusive and unsatisfactory : 1. because if all the
crystals were nitrate of soda, then all the saline mass must have
been soda; and 2dly, if only a part was soda, and the rest
Was muriate, then this must have been decompounded by the
nitric acid: but 3dly, if this could happen, then the whole of
the rhombs might be from the decompounded muriate of soda :
4thly; if the whole of the crystals were rhombs of nitrate of
soda, what became of the cubical crystals of muriate of soda ?
IV. The portion d, with oxymuriate of platina, gave a pre-
cipitate of potash oxymuriate of platina, and by evaporation
soda-muriate of platina.
Here the questions occur, 1. what are the proofs of soda
muriate of platina? 2. What are the proofs, that soda mu-
riate of platina was from free soda, and not from muriate of
soda ? :
To omit nothing supposed to be favourable to the adverse
party, it must be noticed, that ‘“the carbonaceous alkaline
mass above spoken of after fusion did not deliquesce on ex-
posure to even damp air.” 1 never met with such a result, at
least with expectorated matters, and dropsical fluids ; and if
no deliquescence took place with the salts of serum of blood,
it is not unreasonable to account for it from the very small pro-
portion
a)
CO
i
Why the alka-
line mass, did
not deliquesce,
288
Objections to
Dr. Marcet’s
inference,
ON THE UNCOMBINED ALKALY IN ANIMAL FLUIDS,
portion, probably not one fourth of a grain, or at most half a
grain of alkali, in the whole mass; and this by fusion might be
united to form a compound unknown.
To the inferences of my adversary I also object. 1. That it
is assumed, without testimony, that alcohol dissolves a large
proportion of muriate of potash. It is, I believe, admitted,
that this menstrnum dissolves none at all; but if this be an
errour, I demand the proof.
2. It was not admitted, as I reasoned, that acetate of soda
is nondeliquescent ; and therefore the proof 1 offered of the
alkali being potash from the deliquescent property of the ace-
tate was eagerly seized to expose my ignorance, by exultingly
exclaiming, that I had committed a palpable errour. I acknow-
ledge, that I had taken for granted, with most chemists, what
I subsequently admitted was not a fact; but I am now in a
doubtful state of mind, with regard tothis property ; for professor
Berzelius confidently assures me, that acetate of soda was found,
by repeated experiments, to be uniformly nondeliquescent : and
on observing, that in my experiment Ihad found it otherwise,
we agreed, that probably the different results were owing to
the soda I used containing a proportion, - however minute, of
potash, and which I could not perceive by tartaric acid, whereas
that he employed was exempt. — If this be true, it will be a
stronger proof, that the alkali is potash, than the united testi-
monies produced to prove that it is soda.
3. Dr. Marcet argues, that from principle it may be inferred,
that soda, and not potash, is the impregnating alkali, because
the Jatter attracts muriatic acid more strongly than the former.
This is true in the circumstance of single elective attraction ;
but any reasoning from this law, when more than one men-
struum is present, and two or more bases, is fallacious; espe-
cially when the different substances present are not certainly
known. And here I must observe, that I have never contem-
plated potash as existing in an uncombined state in the animal
fluids, but in reality in combination witha destractible acid, or
with animal oxide. This acid, from some trials I was inclined
to propose, is the malic acid ; but I did not venture to offer it
to notice, although I did not abandon the notion: however, I
find from the conversations of professor Berzelius, now in Lon-
don, that he coincided with me in an analogous, if not a simi-
lar
ae
ON THE UNCOMBINED ALKALI IN ANIMAL FLUIDS.
lar result. “ You very nearly,” said he, “* made a capital
discovery ; for I have ascertained, that it is the lactic acid in
union with the alkali of the animal fluids.” I hope the British
public will soon be edified by the translation from the Swedish
language of a work of this most acute chemist, and, as I hear,
by a most able editor. Hence much light will be afforded, espe-
cially in animal chemistry. This fact is, however, only within
the record before us, to repel any a priori conclusion from a
case of simple elective attraction. I had long considered the
case of this kind noticed by my opponent, for it was too glaring
tobe passed by. If reasoning from principle could be depended
upon, I would argue; that, as all animals either immediately or
mediately live upon vegetables, and as vegetables very generally
contain potash combined with acids, or other things destructible
by fire, it is reasonable to conclude, that the fluids of animals
must be impregnated with potash in such a state of combination.
I know it has been argued by some able chemists, that the
potash must be united to muriatic or sulphuric acid, and
soda must be united to some weaker acid, such as carbonic,
lactic, acetous, malic, &c., agreeably to the assumed law, that
the stronger menstruum unites with the stronger basis, and
the weaker menstruum with the weaker basis. But there are
so many exceptions to this rule, that it cannot be justly termed
a law.
289
Lastly, in his P.S. Dr. Marcet says he has instituted the Mere general
statement of
the result inad-
tity, some gallons, of bullocks’ blood, with the same results as missible testi-
process above examined on a very large scale, on a large quan-
on small quantities of animal matter. I believe such evidence
is inadmissible ; for if mere general statements of results be
received as testimony, much errour will be liable to be intro-
duced; as the public in these cases cannot be in possession of
the means of repeating the experiments, and judging of their
accuracy. It is to be regretted, that the author did not render
his experiments instructive, by the necessary detail ; however,
if they were a mere repetition of former ones, the questionable
fact would still remain undetermined.
The chemical world mav now perhaps be furnished with the
means of judging whether or not Dr. Marcet has removed
every shadow of doubt by legitimate inductive reasoning,
VoL, XXXII, No, 154.—Decempggr, 1812.. U My
mony.
290
Authority no
proof,
Reasons why
the author pre-
ferreda jocular
tone,
ON THE UNCOMBINED ALKALI IN ANIMAL FLUIDS.
My oppenent, not content with proofs by experiment, has
endeavoured to command assent by a most respectable autho-
rity ofopinion. But Truth is not the daughter of mere human
authority, but of Time, producing testimonies of sense and of
reason.
I beg to have permission to make a very few remarks, which,
although justifiable, yet being personal, will afford but lenten en-
tertainment, and stil! less instruction, to the public. In mak-
ing this authority the vehicle of his letter, my opponent thinks
proper to express disapprobation of my mode of controversy, and
to more than insinuate, I should not have been honoured with
further notice, but for the ‘* interference” of his friend. Ac-
cordingly, but for this fortunate circumstance the public would
not have been instructed by his letter before us. This conduct,
lt own, I think is rather selfish ; for a public-spirited man will
always make sacrifices of his feelings for the benefit of the
republic. It is, however, good, that the interference overcame
the resolution after four months’ obstinate resistance. The
head and front of my offending was, it seems, to the extent of
an attempt to be jocular, in which I never meant to inflict any
wound on the feelings. It grieves me, certainly, to find, that some
of my expressions were construed, insidiousness—‘‘ Non vul-
nera fidelia amantis, sed oscula blandosa malignantis.” In the
endeavour to expose the inefficiency of the proposed method of
investigation, and to honour illustrious chemists, whose suc-
cessful methods were unworthily disvalued, I preferred the
manner of controversy complained of, to the alternative—a
serious remonstrance. For as my affectionate friend, the Prince
of Philologists, (now no more!) was wont to say, ‘‘ Cantantes
minus via ledit.”
In conclusion ; I would fain hope, that, if this warfare must
be continued, special care will be employed, that nothing be
said or arise, which can reasonably excite* painful sensations in
either party. And if it be agreed, that our axioms and conclu-
* Thave no where charged Dr. M, inthe terms alleged, that he had
committed blunders. I can well spare the word blunder from my vocabu-
lary, having little use for it, although by the law of retaliation amply
justifiable,
sions
HYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY. 291
sions are but inductive reasonings, according* to the known
facts, which therefore are liable to be subverted by the facts
being multiplied, whatever be the issue, no humiliation ought
to be experienced, as the parties will moult no feather,
I have the honour to be,
Dear Sir,
Your most faithful Servant,
GEORGE PEARSON..
f x IX.
On Hygrology, Hygrometry, and their Connexions with the
Phenomena observed in the Atmosphere. By J. A. Dz Luc,
Esq. F.R.S.
To W. Nicholson, Esq.
SIR,
N the third part of my paper on the electric column, pub- Atmospheric
phenomena ime
lished in your Number 124, for December, 1810, where portant to the
I have considered that instrument as an aerial electroscope, I es Fad
have shown the importance of studying all the atmospheric phe- ae "
nomena, before a final decision could be obtained of the ques-
tion agitated for some time, on the nature of water; whether
it is a compound or a simple substance; a question which em-
braces the whole theory of chemistry. Especially I hope to
have made it evident in that paper, that, since atmospheric phe-
nomena are to be considered in the solution of the above ques-
tion, we ought to study particularly all those of the electric and particu-
fluid in the atmosphere ; to which we might be led by the seedeoes "ang
phenomena of the aerial electroscope, provided we did not con. electricity.
nect them with arbitrary hypotheses, nor forget to take into
consideration the nature of the electric fluid, which, from the
great phenomena of lightning and thunder, has evidently a
‘great share in meteorological appearances. My papers, Sir,
* Experientiz ordo prim6 lumen accendit, deinde per lumen iter de-
monstrat, incipiendo ab experientia ordinata et digesta, atque ex ea
educendo axiomata, atque ex axiomatibus constitutis rursus nova experi-
menta.—Nov. Organum F, Baconis.
U2 in
992, HYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY.
in the last numbers of your Journal, were destined to show,
from our own experiments and atmospherical observations, what
are the nature of the electric fluid, and its interference in me-
teorological phenomena ; and I now come again to the same
subject, under another point of view.
Rain not from 1. My observations of the aerial electroscope, published in
ee inthe your No. 124, show, that the changes in the phenomena exhi-
bite by this instrament have no connexion with the state of
moisture in the ambient air.. I proved also, in the same paper,
this important point in meteorology, that rain does not proceed
from a moisture actually existing in the atmosphere. This, if
it be certain, overturns the new theory of chemistry ; for thus
but the pon- rain cannot proceed from any other cause than that of a decom-
ee position of the atmospheric air itself, a fluid sut generis, the
ponderalle part of which must be walter.
Groundsofthe 2. But this conclusion rested on the indications of the hygiro-
conclusion. meter, Myr. De Saassure’s observations, and my own, on high
mountains; in the very region of the atmosphere we saw the
clouds forming around us, and pouring rain, while an instant
before our /y ygrometers testified, that there was very little
eee motsture in the air. Bat here a question arises : is the hygro-
pended on? ‘meter an instrument to be depended upon, for the purpose of
indicating the real quantity of moisture, or evaporated water,
mixed with the air, in the place where it is observed ?
ae ead ae 3. This, Sir, is a very important question, as well in natural,
g "as in experimental philosophy ; and I wish, through your valua-
able Journal, to attract the attention of your readers to this
instrument. I had very little hope of success on this point,
when I wrote my preceding papers in your Journal; because,
from a circumstance which I shall explain Hoesen none of
my hygrometers could be found ; but it is not the case now.
Progress made 4. J had already made some progress in the correspondent
in the inquiry. researches of the indications of the hygrometer, and the phe-
nomena of rain and fair weather, when, in 1786, I published
in London my work, Idées sur la Meétéorologie* ; but I had
carried them much farther, when I delivered to the Royal
Society my papers on hygrology and hygrometry, ys
# This work may be had of Messrs, Dulau and Co, booksellers ia
oho Square.
MYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY: 903
in the Phil. Transactions for 1790 and 1791 ; the subjects of
which I shall here shortly explain, for those of your readers who
do not possess the Phil. Trans.
5. There is no physical instrument, the name of which The hygrome-
terminates in meter, as used for measuring the intensity of the eed at
cause acting upon it, so deserving that name, as the hygrometer moisturein the
described in these papers; for this instrument alone has the 7°
property of measuring the whole extent of the cause which
influences it ; which extent is comprised between two natural and
opposite extreme points, one of which I shall first describe : it is
extreme dryness, or absence of all moisture; which, there-
fore, is an absolute 0. _I have proved, in the above papers to post oF ex-
‘the Royal Society, that this point is effectually obtained, by treme dryness.
placing the hygrometer in a close vessel, filled previously with
a sufficient quantity of fresh calcined lime, taken red-hot from
the kiln.
6. The principle which led me to this method is, that, evapo- Principle on
ration being produced by heat, if red-heat is not destructive of Wisin os ey
a hygroscopic body, it must occasion the evaporation of all the is fouls
uncomlined water the latter contains in its pores. And by pre- bs
vious experiments on various bodies of that kind, I found, that
lime, passing from red-heat to extreme moisture, increased in
proportion of nearly half its weight. I fixed therefore, upon /ime,
and I employed a large vessel, which I filled with red-hot lime.
When it was cool, that vessel having at the top smal] openings
for introducing the hygrometers, (after which they were closed,
and opened only for taking them out,) I took thus the point 0
on a great number of various sorts of hygrometers, of which I
shall speak hereafter. I have described this vessel in the
Phil. Transactions; it is cylindrical, 1 foot diameter, and
3 feet high; I have it still, and when I place in it one of the
hygrometers, ‘the 0 of which had been fixed in it 10 years ago, os varied by
I do not find any sensible difference in this point. Thus, ian
therefore, the point of extreme dryness is perfectly ascer-
tained.
7.. As to the opposite point, that of extreme moisture, I have point of ex-
proved in the same paper, that it was surely obtained by oe mois-
immersing the hygrometer into water ; where it soon attainsa” =~
point, beyond which it does not go, whatever length of time it
remains
994. HYGROLCOGY, AND ITS CONNECTION WITH METEOROLOGY
remains there. This point I have called 100, and the scale is
divided into 100 parts.
Inquiry after 8. Another important object treated in the same paper,
Oa a and which occasioned me much Jabour, was, of what substance
grometers. the hygrometer should be constructed. On _ this particular
point I related a long series of experiments, occasioned by the
first results I obtained by trying many kinds of animal and
vegetable ‘substances : some of which could be used in thin
threads, torn in the length of their fibres; and also in thin
slips cut across the filres. Now, I found, that when used in
the length of the fibres, their lengthening by moisture decreased,
and at last they were even shortened, while the same substances
cut across the fibres continued to lengthen : which at first em-
barrassed me very much*,
Exp. to find 9. I could not decide immediately from these observations,
whether sub- whether the substances taken in length continued to imbibe
Stances cut
lengthwise i im- moisture, while, however, their leah was decreasing ; and
bibed moisture in order to ascertain this necessary point, I contrived a vessel,
hil :
Pe eae described in the same paper. In that vessel I enclosed together
Scale.
ing.
several pairs of hygrometers, made of the same substances ; in
one, it was used in the length, and in the other across the fibres ;
and a beam, indicating the 500th part ofa grain, to which I
Reason why * The reason of the difference in the successive expansion by moisture.
the substance of the same fibrous substances, taken in the /ength and across their fibres,
IS By proceeds from the nature of these substances. The main fires in their
grain, length are united by fibrils, which are seen when we split these bodies.
Sete These small fides form with the larger ones asort of meshes, similar to
those of amet. The first effect of moisture is on the longitudinal fibres,
which it lengthens ; but when it penetrates the meshes, it widens them,
and thus shortens the body ; as the length of a net is lessened by stretch-
ing it across, Moisture therefore acts in two opposite ways on the fi ibrous
substances taken in length, differently: 4 in its progress on the same sub-
stance, and differently also in different substances. And besides, the
whole lengthening i is very small i in allof them. Now, one of these effects
is suppressed by taking the same substances across the fires, namely,
that which acts on the length of the latter ; there remains only that
which acts on the breadth of the meshes, which, if not absolutely pro-
portional to the increase of moisture, is never in an opposite sense. Be-
sides, there is a great gain with respect to the extent of the lengthening,
and therefore of the degrees of the hygrometer ; for instance, a slip of
whulebone, by passing from extreme dryness to catreme moisture, increases
Bia one ninth in Teng’ the
suspended
HYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY. 295
suspended very thin shavings of the same substances as the
enclosed hygrometers; which shavings indicated, by the
increase of their weight, the weight of the water which pene-
tratedthem. I had a léme-vessel by which I first produced
extreme dryness in the vessel containing the instruments; and
when I had observed them in that state, and taken off the vessel
containing the lime, I had also a manner of increasing moisture
by degrees in that of the instruments, observing at each step
the motions of the hygrometers, and the increase of weight of
the shavings.
10, The general results of this experiment were the follow- Results.
ing :—1. That substances taken in Jength continue to imbibe
moisture, though they cease to lengthen, and some even begin
to shorten. 2. That slips cut across the jilres continve to
lengthen so long as the moisture increases. 3. That the slip of Whalebone
whalebone follows very nearly in its lengthening the rate of the periie
increase of moisture, indicated by the increase of weight in its
shavings. From this last result, and from the great elasticity
of this substance, which makes it always sensibly return to the
same length with the same degree of moisture, I fixed on a
slip of whalebone for my hygrometer.
11. Such was the point which I had attained, when I deli- The instru-
vered my papers to the Royal Society ; thus concluded by the mange
determination of an absolute and comparable hygrometer,
which was wanting in the set of meteorological instruments
commonly observed : but by an unlucky circumstance, it still
remains little known, and thus enters very seldom into the
considerations concerning meteorological systems. I had di-
rected, in the construction of that instrument, a very able Ger-
man instrument-maker in London, Mr. Haas; but after he
had sold a few, he. was engaged to go to Portugal, with a pen-
sion from the government ; and since that time, no other instra-
ment-maker had undertaken toconstruct it. But lately a Hano- but now may
verian gentleman, Mr. Hausmann, who lives now at Cumber- Be none.
Jand lodge, near Windsor, seeing that it was a very important
instrument for meteorology, has undertaken its construction,
and having succeeded, he is disposed to make it for those expe-
rimental philosophers, who may wish to have it.
12. So far, however, as may be seen in the above account of The quantity
these experiments, I had only obtained a ratio “between the plein:
quantities
296
given degrees
of the hygro-
meter still re-
mained to be
found,
Mr. De Saus-
gure’s experi-
ments objected
to.
‘The author
resolved to re-
peat them.
Ast. objection.
2nd. objection,
3d. objection,
HYGROLOGY, AND ITS CONNECTION WITM METEOROLOGY.
quantities of moisture, and the degrees of my hygrometer; or
what part each degree was of the whole: but I had not ob-
tained a knowledge of the absolute quantity of evaporated water,
which, in a given bulk of air, corresponded to these degrees ; a
knowledge very essential in the investigation of the cause of.
rain. I saw that this was at least necessary for obiaining more
certainty in meteorological conclusions, i relied in this respect
on Mr. De Saussure’s experiments, as T had not yet had time to
undertake them myself; but I thought then to repeat the same
experiments, for the following reasons.
13. Mr. De Saussure had made these exneriments with his
hair-hygrometer, which was so dissimilar to mine in the rate
of lengthening with the same increases of moisture, that his
results could not-be immediately applied te my instrument.
But especially, he had made all these observations iu the course
of one day ; so that he could only obtain a few immediate
points of comparison, whence he deduced a general law of the
correspondence of the degrees of his fhygrometer with the
quantities of evaporated water in a given bulk of air. This was
a first reason why some natural philosophers did not admit the
results 6f his experiments. There were also some other rea-.
sons, which I shall hereafter mention : but these results were
so important in meteorology, as he himself explained, that I
resolved to repeat the same experiments in such a manner, as to
remove all the objections, which I clearly saw could only affect
the exactness of his experiments, but not their main results. I
shall now mention all these objections, and the manner in
which I proposed to remove them.
14. The first objection, as I have said above, was the short
time employed in his experitments, to which he had been
obliged by the nature of his vessel: I therefore wanted to use
a vessel in which I could prelong these operations as long as I
should find it necessary, A second objection had been made
against the manner in which he first produced extreme dryness
in his vessel, which was by new-calcined salt of tartar; a
substance which has chemical affinities with water, and might
absorb air with it: I wanted therefore to use new-calcined
lime, as I had used it for fixing the point of extreme dryness on
my hygrometers. Lastly, there was an objection against the
manner by which he had determined the quantities of evaporated
: water
HYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY.
tS
6
Be
water in his vessel: it certainly could not be very exact; but
it was sufficiently so, for the final and most important conclu-
sions of a first attempt of these experiments. However, these
objections had rendered the greatest number of experimental
philosophers inattentive to this great step concerning meteoro-
logy, so that it was almost forgotten. This was my first motive
for undertaking the same experiments with the precautions
above explained.
15, I found this attempt much more difficult than I had The experi-
expected ; for it cost me more than two years in useless trials, 1 lati
for obtaining, first, a vessel which would remain air-tight
during all the time that these experiments should require. At
last, however, I succeeded, and the experiments themselves
took me afterWard more than one year. These experiments pojated ina
are related in a work which I published at Paris, in 1803, French work.
under the title of Traité élémentaire sur les Fluides expansibles :
but on account of the present circumstances of Europe, and
this work being in French, a few copies only are come to Eng-
land. This, Sir, makes me desirous to consign to your Journal
a short account of these experiments.
16. My purpose was to ascertain what quantities of Object of the
evaporated water in a known !space of air corresponded to oii
each degree of my hygrometer; and I determined, that this
space should be one culic foot. My first success in overcoming
the difficulties was that of obtaining a vessel, which would Vessel for ma-
remain air-tight during the whole course of these experiments, king them in,
I found, that no vessel could be rendered air-tight so long,
which had a large opening at the top; and that therefore this
opening should be only what was necessary to introduce the
instruments into it. I then procured a glass vessel, about 23
inches high, and 85 in diameter, the opening of which at the
top was only 23 inches in diameter. {[ measured the capacity
of this vessel ; it was not quite one cubic foot; but I ascer-
tained the differences to which I was to proportionate the quan-
tities of evaporated water, so that they might be as 1 grain ina
cutic foot.
17. Before that time, I had foand a sure method of ascer- Method nes
taining the quantities of water successively evaporated in a ves- Sdaniieyor %
sel, without opening it; in order to prevent any exchange of Water evapo-
f i 8 rated in a ves~
the internal with the external air, lest the latter should intro- se] with cer-
duce tainty.
298 HYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY.
duce some moisture with it. This method was to enclose equal
quantities of eater in very thin and small glass bubbles, with a
neck drawn toa very small point, easily sealed with the flame of
@ taper; and before this last operation, I determined the
quantity of water that each contained, by a beam which indi-
cated 1000th part of a grain. These glass Lublles were placed
in the upper part of the vessel on a circular stand, and I had,
outwards at the top, a mechanism for breaking them without
opening the vessel. ‘This method I applied to the glass vessel
above mentioned.
18. Such were the means which I employed for ascertaining
the quantities of evaporated water in a cubic foot of air, acting
Mr. de Saus- on the enclosed hygrometer. But these experiments required
eat ren another condition, which Mr. de Saussure had already intro-
condensed by duced in them: kecause those natural philosophers, who attri-
cold. buted rain to the moiséure in the atmosphere, had supposed,
that this mozstwre was condensated by cold. Mr. De Saussure
had sufficiently proved, that it was not the case, by observing
the effects of the changes of temperature on his enclosed
hygrometer. I was therefore to introduce the same condition
Thevrenee in my experiment, and for this punpose T enclosed also in my
enclosed in the Vessel a thermometer with Fahrenheit’s scale. Lastly, as I in-
vessel. tended to make the same observations on every successive gram
of evaporated water, which would take a very long time;
Extreme mois- having previously found that extreme moisture was produced in
i hal the vessel by a small number of grains of water 5 and even
of water toa that they could not undergo great changes in the degree of
ag footof heat, without some water being deposited in the sides of the
The experi- vessel: this obliged me, in order to obtain the same tempera- -
oe tures in the observations of the effects of each successive grain
autumn for Of evaporated water in the vessel, to make these experiments
uniformity of only in the spring and the autumn ; because, in these seasons,
temperature. : .
=) - J could obtain naturally almost every day in my room the tem-
peratures of 50, 55, 60 of Fahrenheit, on which I fixed for all
these experiments. By this method I was sure, that the tem-
perature would be always the same in every part of the vessel
it being that of the air in the room.
Two series of 19. I made two series of these experiments; one beginning
experiments jn the autumn of 1795, and ending in January, 1796; the
Sadia other beginning in the autumn of 1796, and terminating in
February,
HYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY. 299
February, 1797: each of them began by producing extreme
dryness in the vessel, and proceeded by the evaporation of suc-
cessive gtains of water ; observing afterward the changes pro-
duced on the hygrometer at the three fixed temperatures. In The vessel re-
the course of these experiments E hada proof, that the vessel mained air
remained air-tight. For in order to ascertain the effects of the 8
increase of water at the three temperatures, I consecrated many
days, even wecks, to the observation of each step, by repeating
it many times; which made both sets of experiments last near The experi-
6 months: however, I found no sensible difference in these ments many —
observations from the first to the last day, with every quantity eae
of water; and in ending them, I had an immediate proof,
which it would be too long kere to explain, that the aqueous
yapour, which had been produced in the vessels, had added its
expansibility to that of the air originally enclosed in it.
20. This, I think, was a complete determination of the cor- Rules of hy-
respondence between the degrees of my hygrometer, and the Seance Bags
quantities of evaporated water in one cubic foot of air, at the experiments.
observed degrees of heat. I then undertook to derive from
these experiments general rules of hygrometry. These deduc-
tions begin at p. 325, of the 2d vol. of the above-mentioned
work ; they are given in 13 successive, tubles, of which I shall
only mention, two.
21. In table ii. are united the results of both experiments,
(which differ very little from each other), reduced to their
mean terms, Lach set began at the point of extreme dryness in
the vessel ; a point where the hygrometer stood at O in both.
At that point, no moisture being in the vessel, the change of
heat from 50 to 60 of Fahr. produced no change in the hygro-
meter. During both sets of experiments, the limits of the Limits of eva.
evaporation in the vessel were the same: 5 grains only of water hha ae
could remain evaporated at the temperature of 50; 6 grains at ratures.
that of 55, and 7 grains at 60. Beyond these quantities, at the
Tespective femperatures, a certain quantity of water was depo-
sited on the sides of the vessel in the form of dew ; but when
this effect took place at the temperature of 50, the dew was
dissipated when the heat of my room.came to 55 ; and when
it happened at 55, it was dissipated when the hea/ in the room
arrived at 60. .
22. Thus therefore we have the natural limits of the quanti-
ties
—
S00 HYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY.
ties of evaporated water that can subsist in one cubic foot of air
with these three degrees of heat; but by the rate of its pro-
gress, this correspondence may be continued to higher and
lower temperatures, as I shall explain, after the following indi-
cation of the immediate effects observed on the hygrometer of
each increase of 1 grain at the three temperatures. In the
first two columns of the table, the points of the hygrometer
cease to be indicated at the period when dew appeared on the
side of the vessel.
Tablerobauales: Grelon metas Points of the Points of the Points of the
ture indicated in 1 cubic foot. " hygr. at oes hygr. at tome. hygr. at temp.
by the hygro- 5B. 55°. 60°.
meter at differs ct tt NO a ST en
ent tempera~
3 ° a
cures: 1 15'2 14°5 13'9
2 29'9 28°5 27°6
3 51:6 47°92, 43°2
4 74:9 641 55°
5 $9'8 78'6 68'3
6 93'9 82"!
7 966
Rararkecd 23. This table shows the progress of the effects on the hy-
this table. grometer of the evaporation of the successive grains of water.
These increases were stopped, as I have said above, by some
water being deposited on the sides cf the vessel. This effect
took place for the 6th grain with the temperature 50°, and
for the 7th grain at 55° : however, this happened only when
the grains were entirely evaporated, during which time the
hygrometer had moved ; but there was no fixed point to be ob-
tained correspondent to the new grain of water, since a part of
it at last was deposited on the sides of the vessel.
Accountofthe 24. The tables which follow this, in my work, serve to com-
nee bine these résults, by the rules of interpolation, for obtaining
. the intermediate terms not given by the experiments; and also
to continue the same series, on one side, up to 98 of the ¢her-
mometer, and on the other, for a particular purpose, down to 0.
The table ix., which is the result of all these combinations, is
construeted in such a manner, as to afford immediately the an-
swer to the following questions, very important in meteorology.
Oaestionsan- 1. A point having been observed on the hygrometer in the
- epen
HYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY. 301
open air, what are the quantities of evaporated water in one swered by ta-
cubic foot of that air, at any given temperature ? ble ix.
Il, The points of the Aygrometer and thermometer having
been observed, what is the quantity of evaporated water in one
cubic foot of that part of the atmosphere ?
III. The points of both instruments having been observed, to
what degree ought the thermometer to fall, in order that the
hygrometer should arrive in that air at 100; which point it
must attain before there is any precipitation of water ?
25. The answers to these questions, from the immediate re- yo georce of
sults of my experiments, led to this first conclusion ; that cold a the aic
no diminution, of heat in the atmosphere could occasion in it pel ho dees
the precipitation of such a quantity of water as to produce rain.
clouds pouring rain; which confirmed me in the opinion
already expressed in my work, Idées sur la Météorologie, that
the aqueous vapour, constantly ascending in the atmosphere, Aqueous va-
ceased in great part to act on the hygrometer, being converted Pe'r Kaige
into an aeriform fluid, namely, the atmospheric air, and that ye eas
clouds and rain were produced by the decomposition of this i being con-
verted into
fluid. ] atmospheric
96. Such was the conclusion of all the above hygroscopic air.
experiments ; and with respect to atmospheric phenomena, it See
coincided with the observations of Mr. de Saussureand myself scopic experi-
in the high regions of the atmosphere. Having both long in- ee
habited our mountainous country near the Alps, we had sepa- spheric pheno-
rately followed the same meteorological observations with our anes of the
hygrometers, and we had absolutely ascertained these two!
points.—1. uhat the more we ascend in the atmosphere, the.) . same de-
dryer the air is observed ; and that even, in clear weather, it is ductions form-
dryer in the night than in the day. 3. That clouds, rain, hail, # ae
and thunder, are produced in certain strata of the atmosphere ae Mr. de
which were clear a moment before, and in which one culic foot Saussute-
of air did not contain above two grains of water. Having
both separately, at different times, and also in different parts of
the mountains, made the same observations, and published them
separately, I cannot suppose, that their results can be contested.
‘ "Thus it is certain, that rain is not produced by a moisture exist-
ing in the atmosphere ; and consequently that it proceeds from
a decomposition of the air itself.
47, From what I haye said so far, it may be judged, that the Proofs, that
whole
302 HYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY.
the modern whole of this work was intended to prove, how erroneous was
ie Bist the modern theory of chemistry, the foundation of which is to
neous, suppose, that water is a compound of two substances, called by
its authors hidrogen and oxigen, and that the atmosphere is
principally composed of two fluids called by them hidrogen air
and oxigen air; a system in which, for the explanation of the
greatest atmospheric phenomena, which ought to have been
their first objects of comparison, those of clouds and rain, they
had been reduced to suppose a condensation of the aqueous va=
pour by cold, which supposition the above experiments prove to
be absgiutely erroneous. This is the only point, which I have
here considered ; and indeed it is sufficient to overturn the
whole theory: but in other parts of the work I entered into the
examination of allits parts, beginning with the original experi-
ments from which the composition of water had been concluded ;
and in analysing these experiments I made it manifest, that, far
from being satisfactory, there were many unwarrantable hypo«
theses to be made, in order to connect the facts with the conclu
sion, |
Berthollet’sat- 29. When my work had been published at Paris, Mr. Bers
temptto de- THOLLET, one of the authors of that chemical theory, attempt-
as ai ed, inthe Annales de Chimie, and in another French Journal,
to defend the only resource of that theory, namely, that rain
was the effect of the condensation by cold of the aqueous va-
pour existing in the atmosphere. He acknowledged however
two points, first, that my experiments with respect to the effects
of evaporated water on the hygrometer at different temperatures
had been made with an uncommon accuracy ; and that I had
thus demonstrated the errour of those, who attributed evapora-
tion to a dissolution of water by air, These were two impor-
tant concessions; but being loth to abandon his theory, and
totally unacquainted with meteorological phenomena, he at-
tempted again, as it was absolutely necessary forthe sapport of
his theory, to explain rain by the cold condensating the aqueous
vapour in the atmosphere ; thinking that by transporting the
condensation to very high regions of the air, no objection could
be made from immediate facts : but he was mistaken ; since Mr.
de Saussure and myself had proved, from immediate facts, that
the upper regions of the atmosphere are dryer than those that
we can attain.
29. I
WYGROLOGY, AND ITS CONNECTION WITH METEOROLOGY. 303
29. I answered, in the Annales de Chimie, toevery part of Answered by
Mr. Berthollet’s objections ; and neither himself, nor any other the author.
experimental philosopher, has ever replied ; while, on the con-
trary, many have abandoned the fundamental part of that theory,
the composition of water: and indeed, one of its first inventors, +4, compo-
with whom, having seen his experiments, I had acquiesced in sition of water
his conclusion, and for a time maintained it, I mean Dr. Priestley, sal te
made me himself abandon it, on account of new chemical re- supperters.
sults obtained in his experiments, which he opposed to Mr.
Berthollet.
30. I have been induced, Sir, to give you this abstract of a We are too
work little known in England, in order the more to fix the poet
attention of natural philosophers on the hygrometer, of which theses.
I have thus proved the importance-in natural science. It is
difficult to abstain from making ¢heories on the first phenomena
we observe of a new kind, or from admitting those which ap-
pear probable to us ; and I have said above, that I had at first
acquiesced in that of the composition of water : but by the pro-
gress of experiments, new facts are discovered, and correct the
theories too soon admitted. My long study of every branch
of meteorology, being united with the experiments related in
this paper, which indeed were directed to that object, have de-
monstrated to me this great point in natural philosophy—that it
is impossible to attribute ratn to a moisture actually existing
in the atmosphere ; which alone entirely refutes the new che-
micaltheory. Moreover, all the experiments on the combina-
tions of gasses with other bodies concur to show, that the pon-
derable part of these fluids is water. Lastly, in the above men-
ticned work I proved, as I have done succinctly, Sir, in my paper
published in your Journal for December, 1810, that, when we
consider the atmospheric air as an aeriform fluid, though never
mixed but with a very small quantity of aqueous vapour, all
the atmospheric phenomena are explained.
I may conclude, therefore, that meteorology makes an
essential part of natural philosophy, and that it is not so ob-
scure as it is commonly thought.
1 have the honour to be,
Sir, ,
Your obedient, humble Servant,
J.A.DE LUC.
Windsor.
S04. METEQROLOGICAL JOURNAL.
x.
METEOROLOGICAL JOURNAL.
BAROMETER.
1812. Wind.| Max.
oth Mo.
SEP. 27|S Wj 30°04
2815 E} 29°90
29IN EI 29°90
30} E j 29°90
190th Mo.
Ocr.
=
W | 29°98)
E} 20°08
W} 29°90
W! 20'78
E} 29°32
re § 29°32
EK] 29°40
W{ 29°40)
20°35)
11] W j 29°28
COON OOK WY HY
w
13\S E} 29°16
14;5 Wj 29°14
15| W } 20°39
106. W.) 20°56
17/8 W] 29°56
18} .W { 29717
19|S Wy 28°81
20\N W} 29°54! :
21IN WI 29:74
22/5 WI 2945,
SW 29:92)
25/8 -F} 29°50;
S W 29°74
|
ne es wm |
29'92| 2
W_ | 29°92) 2¢
Min,
to bo
SS
ON
») br Gi
12} Var. | 20°23] 29°
go74
29°40)
29°72
Med.
99°175|
29°620)
29400,
| 29'685)
29°30.
20° 450)
24'730! 5
a) ie 29°468} 69
THERMOMETER.
Max. } Min.
Cea ae erent ee ee es Fe . tl oem Go
Med.
59 } 63°5
53 | 58°O
55 | 560
55 |} 570
48 | 55:0
AS | 56:0
Al | 51:0
44 1 50'5
554 62:0
Al | 52°5
45 } 51:0
40 } 51°'0
46 | 49°5
43 } 40°5
38 | 45'5
37 | 47°0
45 1 510
42 | 465
3 | 480
34 | 45°0
39 | 47:0
50 | 55°5
49 | 540
AD P54:
37 | 45:0
AG | 52:5
4l | 47°5
Al | 48°5
Al | 485
38 | 455
| &4 51°46
The observations in each line of the table apply to a period of twenty-four hours,
beginning at 9 A. M. onthe day indicated in the firstcolumn. A dash depotes Sy the
the result is included im the re
xt following observation.
at
METEOROLOGICAL JOURNAL,
REMARKS.
Ninth ' Month. 26. Windy. Some rain in the night. 28 a.
m. Very foul sky. 28, 29, 30. Rain at intervals in very small
quantity.
Tenth Month.1. A thunder-storm about 1, p.m. which
was chiefly in the W. with heavy showers. 4,5. Much dew.
A storm of wind about midnight on the 5th. 6. Windy. 7.
Misty morning: the trees dripping. 8. Rainbow, several
times repeated between 8 and 9, a.m. Showers followed. 10.
Rainbow, p.m. 11,12. Rain in the night, misty morning.
13. Cirrostratus and Nimbus a.m. sunshine, and showers: a
wet night. 16. Sunshine, with Cumulostratus. 17. Misty
morning. 18. Squally during the night, with heavy showers.
19. Thunder and lightning about 2 p. m. Very heavy
squalls with rain. 20. Sunshine a.m, much wind. 21. Clear’
and calm this evening. 22. a.m. Overcast, windy. In the
evening awet squall, with some lightning. 24. No swallows -
have been since the 19th or 20th. 25. A few swallows ap-
peared again to-day.
RESULTS.
Prevailing winds westerly.
Barometer : highest observation, 30°04 inches ; lowest 28°74 inches ;
Mean of the period 29°468 inches.
Thermometer : highest observation 69° ; lowest 34°.
Mean of the period 51°46°.
Evaporation 0°63 inches. Rain 3°64 inches.
The evaporation was much greater, during the above period than
the amount here stated ; as appears by observations as the Laboratory.
It was probably not less than 2 inches, The situation of the guage
had been changed.
-
PLaistow, Ps L. HOWARD,
Eleventh Month; 18, 1812.
Vou. XKXIII, No, 154.—Ducemser, 1812, X XI.
Pe
305
WATURE AND DETECTION OF METALLIC POISONS.
é*
©
>
XI.
On the Nature and Detection of the different Metallic Poisons.
Ina Letter from Mr. Caaries SYLVESTER.
To William Nicholson, Esq.
DEAR SiR,
WNatere and \ LTHOUGH an inquiry reiative to the nature and detec-
pan ie tion of the different metallic poisons would need no apo-
logy, at any period, for its introduction to the readers of your
metallic pai-
sons, subject Journal, yet I feel it to be the less necessary, at the present
of inquiry. d :
wry moment, from the great interest which has, of late, been ma-
nifested for investigations of this nature; and am indaced,
therefore, te send you the following essay, which was, for the
most part, prepared for a particular purpose many months ago,
Should it tend to lessen any of the difficulties attendant on a
stibject of such importance, or at all interest those who have
devoted themselves to researches of this description, it wil!
fully repay me for the labour of transcribing it.
i remain, dear Sir, :
Your's very faithfully,
CHARLES SYLVESTER.
-
Derly, Nov. 16th, 1812.
I. Arsenic.
White oxi he As a poison the most virulent, and, at the same time, the one
of arsenic. most to be dreaded, from its extreme insipidity, and the con-
sequent readiness with which it may become an instrument in
the hands of the murderer, or be received into the system by
Detection of accident, is the white oxide of arsenic. For the detection of
ie this substance, when thus admitted, various processes have, at
Dr. Bostock’s different times, been recommended ; and the papers of Dr.
Be ee Bostock, published in the 5th vol. of the Edinburgh Medical
red, » and’ Surgical Journal, have, very generally, been thought to
contain the best directions for this purpose. After various ex-
periments he decides in favour of sulphate of copper, and
carbonate of potash, which precipitate the white arsenic under
Objection to the form of Scheele’s green.. It cannot fail to have occurred,
Ihe however, to every one who has repeated these experiments, that
the phenomena produced in this process are very much too am-
biguous toenable a man, where the life of an individual is at
3 ey stake,
ee ee ee
NATURE AND DETECTION OF METALLIC POISONS.
Stake, to swear positively, that arsenic has been detected in his
operations. The alkali employed, whether arsenic be present
or not, uniformly occasions a precipitate, by detaching the
oxide of copper from its combination with the sulphuric acid,
The colour of the deposit, it is true, is not absolutely the same
in both cases; but, when it is recollected, that experiments of
this kind are, for the most part, conducted on solutions coloured
to a greater or less degree from the matters found in the sto-
mach or intestines, this minuteness of distinction will be deemed
scarcely appreciable by the eye even of the most experienced
operator. Such uncertainty ought, most assuredly, not to at-
tend investigations of this nature ; and the process of Dr. Bos-
tock, therefore, becomes objectionable from this circumstance.
The method of detecting arsenic next deserving of remark,
307
Process lately
is one lately recommended by Mr. Hume, of London. It recommended
consists in adding a quantity of subcarbonate of soda to a solu-
tion suspected to contain this metal ; and afterward presenting
to it a small piece of nitrate of silver. It is far preferable, Mr.
Hume finds, to employ the latter salt in a solid form; and he
recommends an angular piece, of the size of a pin’s head, or
thereabouts, held at the surface of the fluid, on the point of a
knife. The existence of arsenic will be shown by a yellow
precipitate, which falls down in ratner abundant quantity,
Whenever arsenical mixtures are operated upon, which have
but little contamination with foreign ingredients, this process
will, undoubtedly, succeed very well; but if ever mariatic
acid be present, and this is always the case where materials
from the stomach are mixed with the fluids under experiment,
the test is then wholly useless, as a muriate of silver will be
immediately formed, and the yellow compound, said to be so
unequivocal in its indication of arsenic, of course be prevented
from appearing. Neither of the processes yet spoken of,
therefore, can receive that confidence, which ought to attach to
by Mr. Hume,
Objection to
it.
investigations of such high importance, This is not a mere spe- The difficulties
culative difficulty, but was fully proved to me daring a course
of experiments made some time ago, in consequence of a case
of poison which came under my notice ; and having, with the
assistance of my friend, Mr. James Oakes, devoted, at that
period, a good deal of attention to the subject, with a view,
proved by ex-
perience.
if possible, to supply the deficiency, we were led to the use of A different
X 2 two
308
process re-
commended,
‘T we tests pro-
posed,
Advantages in
the use of these
tests.
Of thetwo, the
acetate of cop-
per prefer-
able.
Preparation
of the oxya-
cetate of iron.
NATURE AND DETECTION OF METALLIC POISONS.
two reagents, which, I think, will not only be found free from
the objections applicable to those already mentioned, but ap-
peared to cormbige most of the advantages requisite in opera-
tions of such extreme delicacy. Thereagents employed were
the acetate of copper, amd oxyacetate of iron. For the pre-
paration of them it is merely necessary to decompose oxysul-
phate of iron, and sulphate of copper, by acetate of lead, ad-
ding the latter until a turbidness ceases to appear. The result-
ing mixtures should contain as little of the original ingredients
in combination as possible ; particularly the iron test, since an
excess of the oxysulphate, as was observed in our experiments,
suspends the action of the acetate, and prevents its combination
with the arsenic. The presence of acetate of lead is objection
able from its causing a precipitate with arsenic, which cannot
be distinguished by the eye from sulphate of lead. When the
two acetates are properly prepared, they combine with arsenic
with considerable facility ; that of iron producing a bright
orange yellow deposit, and that of copper, green. The de-
composition, however, especially of the former, does not ap-
pear to be complete till they have been suffered to stand a few
seconds. One of the great advantages attending these reagents
is, that their action is independent of the use of alkali, which,
in the two former processes, from the precipitate uniformly
occasioned by its presence, throws considerable uncertainty
over the results of an experiment ; and where the mixtures are
coloured, as will always be the case, in a greater or less degree,
in examining the contents of the stomach, must rob these’
methods of the whole of their value. With the tests here
recommended, the colour of the compounds produced is not of
that primary importance ; for, since almost all their combina-
tions, particularly those of copper, are soluble in water, except
the one produced by an union with the white oxide of arsenic,
the appearance of any precipitate may, without much risk, be
referred to the présence of this metal. Of the two, experience
has confirmed us in a preference of the acetate of copper,
partly from its more sensible action on arsenical mixtures, and
in some measure, also, front the easier mode of its preparation,
As the oxyacetate of iron, however, may sometimes be occa-
sionally resorted to, in order to afford additional evidence of the
accuracy of an experiment, it may be necessary to add, asa
| Pi farther
NATURE AND DETECTION OF METALLIC POISONS. 309
farther direction for its preparation, that the oxysulphate from
which it is obtained, should be made by dissolving iron with
the aid of heat in nitric acid, afterward precipitating the oxide,
and redissolving it in sulphuric acid. The salt thus formed
contains the metal at a maximum of oxidation.
The whole of the above processes for the detection of arsenic Reduction of
of course refer to the cases where it has been exhibited only in th arsenic to
i t : e preferred
a fiuid state. Whenever it can be accomplished, however, by when practi-
far the most satisfactory means of arriving at a knowledge of “ble-
the presence of this substance, is to reduce it toa metallic
state, which may be readily effected, either by subliming it in a
glass tube with the aid of charcoal, or exposed between two
plates of copper, according to the plans recommended in che-
mical works.
IT, Corrosive Sublimate.
For the discovery of corrosive sublimate, the methods almost Oxymuriate
exclusively resorted to until very lately were its precipitation by of mercury.
means of one of the carbonated fixed alkalis, or by lime water,
which detach it under the form of an orange-coloured, or
orange yellow, sediment. Dr. Bostock has since recommended Muriate of tin
muriate of tin; but, to the use of this test there is considera- ae dig
ble objection, inasmuch as a precipitate, very similar in ap- tock. 1
pearance to the one obtained from mercury, is always occa- Objection.
sioned whenever muriate of tin comes into contact with a solu-
tion containing water. This could not fail to render the result
- of any experiment ambiguous ; but should it so happen, that,
from a particular circumstance, the employment of the mu-
riate might be rendered at all desirable, its effect upon the fluid pEsoeG eats
suspected to contain corrosive sublimate should be collated with degree, sur-
the appearance produced from its mixture with an equal quan- ™ounted.
tity of water, since the precipitate occasioned in a mercurial
solution is remarkably more abundant than in the latter case,
and sufficient to dispel all uncertainty arising from this cause.
But a test, at once the most easy of application and satisfactory, Hitcanain
is furnished by means of galvanism, in which the mercury is supplies a
separated in a metallic state. This experiment can be made by —— better
any person, and almest in any situation. It is merely neces- :
sary to take a piece of zinc wire, or in its absence a piece of
| iron
310
NATURE AND DETECTION OF METALLIC POISONS.
iron wire, about three inches in Jength, bent twice at right
‘angles into a shape something like the letter U, but with a flat-
Lead.
Cautions
against its use.
Why not uni-
formly injuri-
ous in these
CASES,
tened bottom*. Its width should be about equal to the diame-
ter of a common gold wedding ring ; and the two ends of the
bent wire must afterward be tied to a ring of this description.
This being accomplished, take a plate of glass not less than
three inches square, lay it as nearly horizontal as possible, and
on one side drop some sulphuric acid, diluted with about six
times its weight of water, till it spreads to the size of a half-+
penny. Ata little distance from this, towards the other side,
next drop some of the svlution supposed to contain corrosive
sublimate, till the edges of the two liquids join together,
After this is done, let the wire and ring, prepared as above,
be laid in such a way, that the wire may touch the diluted acid,
while the gold ring is in contact with the suspected liquid. If
the most minute quantity of corrosive sublimate be present,
the ring, in a few minutes, will be covered with mercury on
the part which touched the fluid. It might be proper to filter
the mixture before submitting it to experiment, or otherwise to
pour it clear from the top ; since calomel, which is so fre-
guently taken as a medicine, might possibly be present, and
give rise to these appearances. The insolubility of this sub-
stance, however, enables us easily to avoid it by the precautions
here suggested. .
HL Lead.
Although lead is not so virulent a poison as either arsenic or
corrosive sublimate, its effects upon the animal economy are so
greatly to be dreaded, that those liable to its influence in ma-
nufactures or domestic life, cannot be too much cautioned
againstit. ‘The use of lead, in the construction of water cis-
terns, pumps, and conduit pipes, would, at first thought, ap-
pear highly objectionable ; and in many instances it is, no
doubt, productive of injury. The reason of its not being uni-
formly so, has been ingeniously pointed out by Gayton de Mor-
veau. Most mineral waters contain a greater or less quantity
of some salt formed by sulphuric acid. This acid is not only
* The Greek 1 is no doubt the figure intended.
the
NATURE AND DETECTION OF METALLIC POISONS. 311
the means of precipitating any lead which may happen to be
dissolved in the water, but has the effect also of completely
coating the interior surface of the vessels with the sulphate
thus formed, which is a substance not liable to decomposition,
_and therefore defends the lead from all future ‘action of any
solvent in the mineral water.
The dreadfal disease called the Devonshire colic was clearly Devonshire
shown by Sir George Baker to be occasioned by the lead ‘con- colic.
stituting the lining of the cider press, and other vessels, and
which was dissolved by the acetic acid developed during fer-
“mentation. The acetic acid is here asserted to be the solvent,
because the malic acid forms a salt with lead which is insoluble.
The effects of this metal have been still more conspicuous Great injury
in its use by wine merchants to correct the acidity of wine, done by wine
The practice was at one time so common in France, that in a Ss &:
particular year, when much sour wine prevailed, many thou-
sands of people are said to have fallen victims to its influence ;
and had it not been for the interference of government, it is
impossible to say how widely this dreadful evil might have ex-
_ tended itself,
In the new rum of our West-India colonies the presence Lead present
of lead has been marked by still more deadly consequences, 2 new rum.
It became a matter of great surprise, however, that, after this
liquor had been kept in casks for twelve months, it Jost its dele-
terious qualities. The lead employed in the vessels for the
manufacture, but more especially in those for the distilla-
tion of rum, could not fail to introduce this metal in great
' quantity through the medium of the acetic acid, which is a con-
stant product of fermentation ; and had it not been for a cir-
cumstance about to be mentioned, it is difficult to conceive
where the calamity might have terminated. Nature, however,
in the shape of accident, stepped in as mediator, and redeemed
the lives of those destined to drink the fascinating potion. It
was before observed, that the ram lost its poisonous property
by remaining a certain time in the casks; yet, although the
fact was known, and the evil remedied, many years ago, I am
not aware that any one has accounted for the change produced How thisis
in theliquor. About two years since, my friend, Dr. Forester, remedied by
of this place, gave an interesting lecture, on behalf of the keeping.
Literary and Philosophical! Society, upon the subject of poisons ;
and
312
Mode of pre-
ic
paring gal
-acid.
A sensible test
of lead,
Means of de-
tecting lead in
wine,
Lead should
not be used in
dairies.
NATURE AND DETECTIGN OF METALLIC POISONS,
and it was not till then, that I became acquainted with the cu-
rious facts above mentioned, It immediately occurred to me,
that gallate of lead was insoluble ; and I lost no time in mak-
ing some experiments, to ascertain the fact. The method by
which I prepared some gallic acid for the purpose may, per-
haps, be new, and not wholly uninteresting, to some of your
readers. My first step was to make a strong tincture of nat-
galls in proof spirit. To this was added, by little at a time,
a nearly saturated solution of isinglass, till the whole of the
tannin was precipitated. The liquor separated from the coa-
gulum at first appeared rather opaque, but without colour.
By standing at rest for a few days, a deposition of flocculent
matter took place, consisting of gelatine and tannin, which left
the liquor transparent and colourless. This I considered as a
solution of gallic acid, nearly pure. At all events, it did not
contain any substance which prevented its being an excellent
test for iron or lead. I soon found, that in very dilute solutions
of lead, where sulphuric acid, or a sulphate, produces no visible
precipitate, the presence of this metal was made sensible by the
aid of,the gallic acid. This confirmed my suspicions on the
subject, and left me in no doubt as to the real cause of the rum
losing its pernicious qualities ; for, since the joint existence of
lead and gallic acid in any fluid is impossible, from the formas
tion of an insoluble gallate, the lead of the rasa becomes
precipitated by the gallic acid furnished by the oak cask.
These facts supply an excellent, though indirect, method of
ascertaining, in many instances, whether lead be dissolved in
wines. If, on testing the wine with iron, it is found to contain
gallic acid, we may safely infer, that no lead is present ; but if
no gallic acid be detected, then either this acid, or the sul-
phuric, may be added, which will precipitate the lead. in the
form of a white powder. Sulphuret of potash, or lime, may
also be employed, which will occasion a blackish deposit.
The, prevailing use of lead in dairies is very objectionable,
especially when the milk is immediately used as an article of
food. On the separation of the curd and butter, the dissolved
lead will, no doubt, exist in the whey. When milk is kept too
long in warm weather, the acetic acid is formed, which takes
up the lead; and it is a fact well known in dairies, that milk
remains sweet longer in leaden vessels than any other, This
is,
ON FACILITATING THE GROWTH OF ROOTS FROM LAYERS, 313
is, mistakenly, attributed to the coolness of the lead; but the
true cause is as above mentioned. The evil would, in all, pro-
bability, be much more considerable, were it not for the pre-
sence of the saccholactic acid, which takes the lead from the
acetic acid, and forms an insoluble compound.
LV. Copper.
The only other metallic substance likely to be taken into the Copper.
' stomach is copper ; and for this the beautiful blue colour pro-
duced in its solutions by pure ammonia, is the most decisive Ammonia its
and satisfactery evidence that can be required. ae al ei
As a general reagent, either for the present metal, or for Gororal test of
lead, mercury, or arsenic, none, in point of delicacy, can metallic poi-
exceed liquid sulphuretted hidrogen. It detects the smallest °°"
quantity of metallic matter present in any mixture; and
although the coloured media, in which experiments of this
sort are generally obliged to be made, prevent that reliance
upon the mere colour of a precipitate requisite to give this test
an exclusive preference; yet it may frequently abridge the
labour of an operation very considerably, and at once decide whe- '
ther the poison has been metallic or otherwise. In conducting general pre-
this sort of experiments, the recommendation of Dr. Bostock, cautions.
to view the result by reflected, and not by transmitted, light,
is highly important ;- and in no case, perhaps, ought a decision
to be given without comparing the effect of every test on the
suspected mixture with the phenomena it presents in fluids of
known composition.
XII.
On facilitating the Emission of Roots from Layers. By T. A.
Knicur, Esq. Pres. H. S*,
T is my custom, annually, to repeat every experiment that Experiments
‘occurs to me, from which I have reason to expect informa- veined es ei
tion either in opposition, or in favour, of the opinions I have tion of sap in
advanced respecting the generation and motion of the sap in ‘recs.
* Trans, of the Hort, Soc, vol. I, p, 255,
| trees ;
314 ON FACILITATING THE GROWTH OF ROOTS FROM LAYERS.
trees; and one of these experiments appearing to point out an
improvement in the propagation of such trees by laying, as do
not readily emit roots by that process, I send the following state-
ment, under the hope that it may be acceptable to the Horti-
cultural Society,
Sap descends | have cited, in a former communication*, apart of the
oe aie evidence, upon which I have inferred, that the sap of trees
bork” descends from their leaves through the bark; and FE shall
here only observe, in support of this opinion, that, if a pieee
Proof of this, Of bark be every where detached from the tree, except at its
upper end, it will deposit, under proper management, as
much, or nearly as much wood, upon its interior surface, as
it will if it retain its natural position ; and that the sap which
generates the wood, deposited in the preceding circumstances,
must deseend through the bark, as it cannot be derived from
any other source.
Sap employed When a layer is prepared, and deposited in the ground,
moe eager the progress of the sap, in its descent towards the original
roots in a lay- roots, is intercepted upon the side where the partially de-
bhi tached part, or tongue, of the Jayer is divided from the braneh ;
and this intercepted sap is, in consequence, generally soon em-
ployed in the formation of new reots, But there are many species
of trees, which de not readily emit roots by this mode of treat-
ment; and I suspected that, wherever roots are not emitted by
layers, the sap, which descends from the leaves, must escape
almost wholly through the remaining portion of bark, which
counects the layer with the parent plant. I therefore at-
tempted, in the last and preceding spring, to accelerate the
emission of roots by layers of trees of different species, which
do not readily emit roots, by the following means, having de-
tached the tongue of the layers from the branches in the usual
manner,
In layers Soon after midsummer, when the leaves upon the layers
en ® had acquired their full growth, and’ were, according to my
been formed, hypothesis, in the act of generating the trne sap of the plant,
the layers were taken out of the soil ; and I found, that those
of several species of trees did not indicate any disposition to
generate roots, a small portion of cellular bark only having
# Horticultural Transactions of 1811; Journal, vol, KXXIL p. 350,
; i ; — issued
JAMROSADE CULTIVATED IN FRANCE. ig eS
issued from the interior surface of the bark in the wounded
parts. I therefore took measures to prevent the returm ofthe return of
the sap through the bark, from the layers to the parent trees, nage ong
by making, round each branch, two circular incisions through vented by re-
the bark, immediately above the space where the tongne of ™0v#! of bark,
the layer had been detached; and the bark, between these
incisions, which were about twice the diameter of the branch
apart, was taken off. The surface of the decorticated spaces
was then scraped with a knife, to prevent the reproduction
of the bark, and the layers were recommitted to the soil;
and at the end of a month I had the pleasure to observe
that roots had been abundantly emitted by every one. In and roots were
other instances I obtained the same results, by simply scraping Produced.
off, at the same season, a portion of the bark, immediately at
the base of the tongue of the layers, without taking them out
of the ground.
By the preceding mode of management, the ascending Effect of this
fiuid is permitted to pass freely into the layer te promote its M@22sement.
‘growth, and to return till the period arrives at which layers
generally begin to emit roots: the return of the sap through
the bark is then interrupted, and roots are, in consequence,
emitted ; and I entertain little doubt that good plants of trees,
of almost every species, may be thus obtained at the end of a
singie season. I wish it, however, to be understood, that my
experiments have been confined to comparatively few species of
trees ; and that I am not much in the habit of cultivating trees
of difficult propagation.
XIII.
On the Cultivation of the Jamrosade (Eugenia Jamlos L.) in
the National Garden at Paris. Abridged from the account given
by M. Txoutn, in the Annales du Museum, V.1, p. 357.
_ By Richarp Axruony Sauispury, Esq. F. B.S. O*
4 | VHE jamrosade, or engeniazamlos of Linné, is one of those Jamrosade, or
. trees, the fruit of which is seldom brought to perfection in *°° apple.
Europe.—In Hindostan, where it grows wild, it is called amlos,
* Horticult, Trans, vol. 1, Appendix, p. 11.
or
316
Described,
The fruit.
SAMROSADE CULTIVATED IN FRANCE.
or jambose, and in those colonies where it is cultivated, jamrosade,
or rose apple. There are several varieties, differing in the size
and colour of their fruit; some red, or reddish; others white
and smaller. Rumph calls the last variety Jambosa Sylvestris
alla, and this is the tree I now propose to describe.
The species being already well known and figured, I shall
only mention the differences peculiar to this variety with white
fruit, its habit at Paris, and the method there adopted to make
it produce fruit.
Our tree is at present about 11 feet high, with a stem 2
inches and a half in diameter at the base, branching from below
the middle into a pyramidal head. The leaves are undivided,
smooth, opposite, of a deep green, coriaceous, and not unlike
those of some Peach trees, but larger. The buds push forth
young leaves in the beginning of summer, of a most lively red,
which change gradually to their permanent deep green colour.
The bunches of flowers also appear at this period, terminating
the branches, from 2 to 6 being clustered together. Petals, 4,
greenish white, about as large as those of apple blossoms.
Stamens very numerous, in a tuft half as long as the petals,
their filaments pale violet colour towards the top, where they
diverge, their anthers yellow. Pistil, longer than all, is inserted
like the stamens, petals, and 4 divisions of the calyx upon a
globular germen, which swells into a green fruit, gradually
changing to white witha pale rose coloured tinge on the side
exposed to the sun.
In size and shape, the fruit is not very unlike a medler : its
flesh rather firm, but easily broken, from 2 to 3 lines thick,
slightly acid, and perfumed with a smell approaching that of the
tose, from which it has acquired the name of rose apple in some
of the French colonies ; in the middle are several nuts, easily
detached from the flesh ; if there is only a single nut, it is sphe-
rical, but when more are perfected, as is often the case, they be-
come angular in the parts which toucheach other. The shell
of the nut is thin and brittle, inclosing a greenish white kernel,
which easily breaks into irregular pieces. The cavity of the
kernel, varying in size and figure, but more or less oval, is lined
with a brown pellicle, which adheres very slightly. These fruits
ripen from September till December, and though not actually nutri-.
tious,
JAMROSADE CULTIVATED IN FRANCE. i
tious, their perfumed flavour renders them very agreeabie to
most palates,
The individual one above described was brought from Hindos- Its introduc-
tan in 1765, by the abbé Galois, and placed in the late Mr. Le- 20> "te
monnier’s stove at Versailles. Though very young, by plunging
it in the tan-bed, it soon flowered, but never ripened fruit till
1786. When it had attained the height of 6 feet, it was trans-
planted into a small box, and exposed gradually to the open air,
during two of the hottest months of the year, but afterward re-
moved back to the tan-bed.
In 1794 this tree was added to the National collection, and Attempt to
being stout and vigorous, I determined to treat it more hardily. TH hea
During winter, instead of the tan-bed, it stood on the floor of
the stove, but near the flue, and during summer it was exposed
to the open air, in a sheltered southern exposure, not housing
it till October, This method of culture, however, did not agree
with it ; for, soon after being put out, most of the leaves fell off,
and those which remained, as well as the ends of its branches,
turned yellow ; a plain indication of its sufferings from the cold
nights. Nevertheless, the great heat of our Paris summer soon
restoring it to its ordinary vigour, numerous young shoots, and
many flowers pushed out, but they fell off without producing
fruit. In this way, I persisted to cultivate this tree till last
spring (1801), being anxious to try, if in so many years, it might
not be habituated to our climate ; but it annually underwent
the same alteration of sickness and health already detailed*.
At this period, wishing to make it produce fruit, I thought all T,eatment to
that might be necessary would be a large portion of air with make it pro-
very great heat. For thispurpose, it was left in the great stove ee
at the foot of a very white wall, which, by reflecting the ravs
of the sun, increased the heat still more, andthe tree was so
placed as to receive the rays perpendicularly. ‘The air was suf-
fered to blow freely round it, and it was deluged with water, in
consequence of the great evaporation produced by so much heat |
and air.
My wishes were thus completely fulfilled ; the tree grew most Successful.
luxuriantly, being covered in June with numerous flowers,which
* This account does as great honour to the candour of one of the
first gardemers in the world, as his detail of the insertion of the several
Parts of the flower does to his botanical abilities. —Sec.
were
318
Seeds sown.
‘Treatment of
the seeds,
Mode of sow-
ing,
The plants
JAMROSADE CULTIVATED IN FRANCE.
were rapidly fecundated, the greater part of them being suc
ceeded by ripe fruits, of which I gathered more than 40. Some
of the finest are preserved in the gallery of Natural History ;
of others, which fell off, [ have already sown the seeds: and
others still on the tree will be suffered to remain till they drop
off spontaneously, that I may be quite certain their seeds are
perfectly ripe. From an examination of the kernel, which soon
changes to a hard, horny substance, it is not surprising, that all
the seeds imported from abroad have hitherto failed, unless they
have been sent packed in earth ; and I therefore deemed it ne-
cessary to sow them in a few days after they fell from the tree,
To make success in this point doubly sure, I employed a
method, the good effects of which I have often experienced.
This was, after taking the nuts out of the fruit, to put them in
my breeches pocket for 2 or 3 days, This sort of animal bath
is preferable to the custom which has hitherto prevailed of im-
mersing many seeds of hot climates in pure water.
I finally sowed these nuts about half an inch deep in pots of
earth, plunged in a very gentle hot bed. At the approach of
frost they will be removed to the tan-bed of the stove, when
the essential point to attend to, will be to moderate the humi-
dity, heat, and light, so that the young plants may not appear
till spring.
I dare not hope that this tree will soon be naturalized to live
may probably jn the open air in any part of France; for, its buds (gemmz)
thrive in a
temperate
stove.
have no scales ; but we may reasonably expect, that the plants
raised from seeds here will not be so delicate as imported plants,
and that they may succeed in a temperate stove, or orangery ;
nay, it is even possible, that such plants may survive through
winter in some of the warm spots under our southern maritime
alps, or in the island of Corsica. For this purpose, they should
be planted with orage trees, citron trees, and guava trees,
among which the jamrosade thrives in its native country, or
such colonies as it has been transported to.
XIV.
SUGAR FROM STARCH. 319
XIV.
Letier from Dr, Tuthill on the Sugar from Potato Starch.
To Mr. Nicholson.
DEAR SIR,
AVING learned, that professor Berzelius had brougbt faveation of
intelligence to this country of a very remarkable change susat from
produced in wheat starch by the action of dilute sulphuric” :
acid at a high temperature, as discovered by M. Kirchoff, of.
theimperial academy of St. Petersburgh, I was desirous of as-
certaining whether the feecula of other, vegetables, submitted
to the action of the same fluid, at the same temperature, would
exhibit a similar phenomenon. For this purpose I took eight poatostarch.
pounds and three quarters of potatoes, grated them, and placed
the pulp on asieve. Cold water was then slowly poured upon
this pulp as long as it passed turbid through the sieve, and the
liquor was suffered to stand in the vessel that received it till it
became clear. On pouring off the clear liquor, the feecula of
the potatoes was found at the bottom of the vessel ; and, when
dried by a very gentle heat, weighed a pound and a half. To
this feecula were added six pints of distilled water, and a quar-
ter of an ounce by weight of common sulphuric acid in an
earthen vessel furnished with a cover. The mixture was kept A poundanda
boiling for thirty-four hours without intermission, the vessel halt et Lain
‘being covered, and the loss by evaporation carefully supplied by of water, and
the frequent addition of distilled water, so as to preserve the same °¢ cece of
quantity as at the commencement of the operation. For the first Suphurie acid
twelve hours I could perceive no change in the sensible proper- ee Leen! :
ties of the vapour. At theexpiration of twenty-four hours the ¢our nati e!
liquor had evidently become saccharine, and this quality conti- In twenty-four
nued fo increase as the boiling was prolonged. Thirty-four ai pa cus
hours after the commencement of the ebullition, half an ounce ;ine,
of finely-powdered charcoal was added, and the boiling con-. After $4 hours
tinued for two hours longer. The acid was then saturated by ee ss
lime that had been very recently burned, and the boiling con- coal wasadded.
tinued for half an hour; after which the liquor was passed After two
through a piece of calico, and the substance remaining on the mee Acar
_ filter-washed by the repeated effusion of warm water. This rated by lime.
“substance, when dry, weighed seven eighths of an ounce, and 5. ooiutile pre-
_ consisted of charcoal and sulphate of lime. The clear liquor cipitate.
: ‘ Saran tae : - Clear liquor
Was now evaporated in a water bath to the consistence of si- evaporated.
rup,
— 820 SCIENTIFIC NEWS.
rup, and set aside to crystallise. In eight days it was converted
into a crystalline mass, having nearly the sensible properties
pea oat a: of common brown sugar mixed with a little treacle. The
seventh part of weight of the saccharine matter thus obtained from. eight
the weight of pounds and three quarters of potatoes, and which I conceive to
the potatoes,"
one pound and a quarter.
One pound of this crystallised saccharine matter was now
tedissolyed in four pounds of distilled water, and by the ad-
dition of a quarter of an ounce of yeast submitted to alcoholic
fermentation. In ten days the temperature having varied from
44° to 540, the smell of the liquor first indicated that the
alcoholic fermentation was just beginning to pass into the
acetous. The whole was then instantly submitted to distillation,
and the process continued till a pint anda half of fluid was
collectedin the receiver. This on being redistilled produced
two ounces and five eighths by measure of dilute alcohol, of
which a cubic inch, the mercury in Fahrenheit’s thermo-
meter standing at 45° and in the barometer at 2219 inches,
weighed 245 grains. I have therefore concluded from the
accurate experiments of Sir Charles Blagden, that the two
ounces and five eighths of dilute alcohol thus obtained con-
* tains fourteen drachms by measure of proof spirit.
oo? JS Lam. dear Sir, very truly your's,
October 28, 1812. G. L. TUTHILL.
Soho Square.
SCIENTIFIC NEWS.
New Explosive Compound.
Notice has been received from the Continent of a new explo-
sive compound, upon which Sir Humphrey Davy has made some
éxperiments; and it has also been produced by others. The
present shortstatement is all that I can on this occasion insert.
Nitrate of ammonia is to be dissolved tosaturation in water,
and exposed ina basin to a low temperature, such as that of
ice, or rather the freezing mixture of ice and salt.—A vessel
containing oximuriatic gas is then inverted in the solution.
The. gas becomes absorbed, and the so lution ascends ; ; and,
after one. or two hours, a small ‘por: of heavy oil is found
at the bottom of the basin. Of this oil if a quantity of the
size of a pin’ s head be put into contact ¥ ‘ith ‘olive oil, a violent
and dangerous explosion takes place. ‘
A friend who repeated this » -expetiment, used a four ounce
phial of the gas and put. his olive oil in a small platina
- spoon. The spoon was destroyed by the explosion.
be intermediate between cane sugar and grape sugar, weighed
Manner ifthe Growth of Bas
By as Vibe PY dion @,
‘Rind
Bark gr
vue bark
Albram
Wood
JOURNAL
NATURAL PHILOSOPHY, CHEMISTRY,
AND
THE ARTS.
SUPPLEMENT TO VOL, XXXII.
ARTICLE I.
Observations on the Measurement of three Degrees of the Me-
ridian, conducted in England, by Lieut. Col. William Mudge.
- By Don Joseru Ropricuez. From the Philosophical
Transactions for 1812, p.321.
HE determination of the figure and magnitude of the earth problem. To
has at all times excited the curiosity of mankind, and the aap oan
history of the several attempts made by astronomers to solve macnitude of
_this problem might be traced to the most remote antiquity. the earth
But the details of the methods pursued by the ancients on this
subject being extremely vague, and their results expressed in
measures of which we do not know the relation to our own,
in fact give us very little assistance in learning either the figure
or dimensions of our globe.
It was not till the revival of science in Europe, that the was considered
two great philosophers, Huyghens and Newton, first engaged by Huyghens
in the consideration of this question, and reduced to the known aaa ng
laws of mechanics, the principles on which the figure of the
earth should be determined.
They demonstrated, that the rotatory motion should occasion as determina-
differences in the force of gravity in different latitudes, and he Kes Pheer
Consequently, that parts of the earth in the neighbourhood of saitbe ;
the equator should be more elevated than those near the poles.
SuPPLEMENT.—VoL, XXXIII. Noa, 155. 2 The
322 FIGURE OF THE EARTH.
ee onthe The most simple hypothesis, which first presented itself to
rpothesis of ahem e .
ee cikaa WELT their imagination, was that which supposed the earth to be
uniformly throughout composed of the same kind of matter, and its sur-
dense, and im- ¢,... 4} 1 pa " : 5 ioe
pattecdy Acie ines that of a spheroid generated by revolution round its axis.
would elevate Lhis hypothesis, adopted by Newton only as an approximation
the equatorial to the truth, is, in fact, perfectly consistent with the equili-
more thanthe |, “it ; ail,
polar regions, librium to which pariicles in a state of paste, or of tardy
fluidity, would arrive in a short time after their present motion
was impressed ; and the eccentricity derived from this hypo-
thesis is at least not very remote from that which actually ob-
tains in the present state of consistence and stability which the
earth has since acquired.
But geological © But the homogeneity of the matter, of which the earth con-
Gbservations (0.0) Ae a ional . hicl
show that the SiSts, is at variance with all geological observations, which
(external part prove evidently that at least 5000 toises of the exterior crust
of the) earth .- fi “ d £ . st f h 2 tt 3
is not homo- +8 formed of an immense mass of heterogeneous matters, vary-
geneous, ing in density from each other ; and upon the supposition of
a state of fluidity of the whole, it should follow, that the strata
should successively increase in density from the surface to-
wards the centre, that the more dense would accordingly be
subjected to less of centrifugal force, and consequently that
the spheroidical form resulting from this cause would be less
eccentric than would arise from a state of perfect homoge-'
neity. .
—s i the The most simple, as well as the most effectual means of
problem, by _ oe. 5 : A
resainiee es verifying the hypothesis respecting the figure of the earth, is
veral arcs of to measure in the two hemispheres several arcs of its meri-
the meridians. gions in different latitudes, at some distance from each other.
On this subject it must be allowed, that the Academy of
Sciences at Paris set the example, in giving the original im-
pulse to the undertaking, and not only commenced, but put’
in execution those parts of the plan which were most difficult
and most decisive.
The first meas The results of the first measurements made of different
rements, a «4 .
ak gamgeS at arcs on the meridian of different parts of the world, were
brations of | found to be perfectly conformable to the expectations of:
Peadiias, Huayghens and of Newton, and also with experiments made
showed that .
the polar re-. on the vibration of the pendulum in different latitudes ; and they’
cea flat Jeft no doubt that the earth was in fact flattened at the poles ;
esta
FIGURE OF THE EARTH. | 323
“establishing thereby one point extremely iateresting in natural
philosophy.
These results, however, did not correspond with sufficient Imaccuracy of
accuracy for ascertaining with precision the degree of eccen- the earlier
ae : : ° : measures.
tricity, or even the general dimensions of the earth; as might
naturally be expected, when we consider the necessary imper-
fection of the means then employed in these operations, and
the great difficulties that are to be encountered.
For the purpose of making a nearer approximation to the
true dimensions of the earth, and of verifying former mea-
surements, it is necessary, in some instances, to repeat them,
and also to make others in different situations, which may be
expected to be improved in proportion to the progress that is
made in the means of perfecting the several departments of
science.
At the commencement of the French revolution, men of Grand under-
science took advantage of the general impulse which the hu- sane ee
man mind received in favour of every species of innovation or in France and
change, and they proposed making a new measurement of an 5P#iB:
arc of the meridian in France, for the purpose of establishing
anew system of weights and measures, which should be per-
manent, as being founded on the nature of things.
A commission, composed of some of the most distinguished directed by a
members of the Academy of Sciences, was charged to form Weems de
the plan of these operations, which were to serve as the basis :
of the new system. They invented new instruments, new
methods, new formule ; and in short almost the whole of this
important undertaking consisted of something new in science,
Two celebrated astronomers, Delambre and Mechain, were and performed
engaged to perform the astronomical and geodetical observa- by Delambre
tions, and these they continued as far as Barcelona in Spain, 224 Mechain,
The details of their operations, observations, and calculations,
were subsequently examined by a committee of men of science,
many of whom were foreigners collected at Paris, who con-
firmed their results, and by the sanction of such an union of
talents, gave such a degree of credit and authenticity to their
conclusions, as could scarcely be acquired by other means.
Since that time, in the year 1806, Messrs, Biot and Arago, Continuation
members of the National Institute, were sent into Spain for a
the express purpose of carrying on the same course of opera- go to Formen-
Y2 tious *=**
$24 YIGURE OF THE EARTH.
tions still farther southward, from Barcelona as far as For-
meutera, the southernmost of the Balearic islands. Fortunately
this last undertaking, which forms a most satisfactory sup-
plement to the former, was completed by the month of May,
1808, at a period when political cireamstances would not ad-
mit of any further operations being pursued, as a means of
verifying the results, by measuring a base which should be in-
dependent of those formerly obtained in France.
Verification of In the year 1801, the Swedish Academy of Sciences, encou-
the Lapland : Sie ane
ee by raged by the success of the operations conducted in France,
the Swedish sent also three of its members into Lapland, to verify their
academy. former measurement, taken in 1736, by new methods, and by
the use of new instruments, similar to those which had recently
been used in France, and of which the National Institute made
a handsome present to the Swedish Academy. ‘The results of
this new undertaking, which terminated in 1803, were drawn
up by M. Svanberg, and are highly interesting, by their exact-
ness, by the perspicuity of the details, and even a certain
degree of novelty given to the subject by the arrangement
adopted by the learned author M. Svanberg. ;
The agree-
ment of these able manner, the general results of those which had preceded,
in eblltr tae and gave very nearly the same proportion for the eccentricity
the general re- and other dimensions of the globe, so that there would not
sults
earth being flattened at the poles, had there not been a fourth
" measurement performed in England at the same time as that.
undertaken in Lapland, the results of which were entirely .
va ae reverse, This measurement, which comprised an are of 2° 50’,
t i;
air cf ff was undertaken by Lieut. Col. Mudge, Fellow of the Royal
hei _ Society, with instruments of the most perfect construction that
england. had ever yet been finished by any artist, contrived and executed
SH ah ’
for that express purpose, by the celebrated Ramsden. The
details of the observations and other operations of Lieut.
Col. Mudge, may be seen in the volume of the Philosophical
Transaetions for the year 1803; and one cannot but admire
the beauty and perfection of the instruments employed by that »
skilful observer, as well as the scrupulous care bestowed on
under circum- every part of the service in which he was engaged. Bengal:
stances of pe- lights were employed on this occasion, as objects at the several
stations,
These new measures were found to confirm, in a remark- .
have remained the smallest doubt respecting the figure of the ;
FIGURE OF THE EARTH. 395
stations, and their position appears to have been determined culjar advan-
with the utmost precision by the theodolite of Ramsden, which tage:
reduces ali angles to the plane of the horizon, and with such
a degree of: correctness, that the error in the sum of the three
angles of any triangle, is scarcely, in any instance, found to
exceed three seconds of a degree, and in general not more than
a small fraction of a second.
Accordingly the geodetical observations were conducted
with a degree of exactness, which hardly can be exceeded ;
and even if we suppose for a moment, that the chains made
use of in the measurement of the bases, may not admit of
equal precision with the rods of platina employed in France,
nevertheless, the degree of care employed in their construction,
in the mde of using them, and the pains taken to verify their
measures was such, that no error that can have occurred ia
the length of the base, could make any perceptible difference
in the sides of the series of triangles, of which the whole ex-
tent does not amount to so much as three degrees.
Nevertheless, the results deduced by the author, from this but which in.
measure alone, would lead to the supposition, that the earth, ig ge
instead of being flattened at the poles, is, in fact, more elevated more elevated
at that part than at the equator, or at least, that its surface is lage
not that of a regular solid. For the measures of different equator.
degrees on the meridian, as reduced by Lieut. Col. Madge,
increase progressively toward the equator.
The following table of the different measures of a degree Table of the
. eet sc - 1: . measures of 4
jn fathoms, is given by the author in his Memoir. dentce “of Tak.
i Latitude. Se ee
52° 50’ 30” 60766 in going south-
52 38 56 60769 ward.
52 28 6 60794 .
ED. 2. OGY 60820
Ft oe 00849
51 25 18 60804
51 13 18 60890
51 2 54 60884
The singularity of these results excites a suspicion of some This singular
4ncorrectness in the observations themselves, or in the method result,
of calculating from them. The author has not informed us in
| ; his
326
if erroneous,
is most proba-
bly so from
the celestial
observations.
The usual
method of
finding the
degree, by
dividing the
total are in
fath. by its
measurein deg.
and parts, will
not detect the
errors of obser-
wation,
“Calculations by
the author,
by means of
the spherical.
anglesin
Delambre’s
method.
FIGURE OF THE EARTH.
his Memoir, what were the formulz which he employed in the
computations of the meridian ; but one sees, by the arrange-
ment of his materials, that he made use of the method of the
perpendiculars without regard to the convergence of the meri-
dians ; and although this method is not rigorously exact, it can
make but a very few fathoms more in the total arc, and will
have very little effect on the magnitude of each degree. It
is therefore a more probable supposition, that, if any errors
exist, they have occurred in the astronomical observations. But
it is scarcely possible to determine the amount of the errors, or
in what part of the arc they may have occurred, excepting by
direct and rigorous computation of the geodetical measure-
ment. I have therefore been obliged to have recourse to calcu-
lations, which I have conducted according to fhe method and
formule invented and published by M. Delambre.
_ The means generally employed for finding the extent of a
degree of the meridian, consists in dividing the length of the
total arc in fathoms, by the number of degrees and parts of a
degree deduced from observations of the stars ; but if these
observations are affected by any error, arising from unsteadi-
ness of the instrument, from partial attractions, or from any
other accidental causes, then the degrees of the meridian will
be affected, without a possibility of discovering such an error
in this mode of operating. It is consequently necessary, in
such a case, toemploy some other method, which may serve
as a means of verifying the observations themselves, of detect-
ing their errors, :f there be any, or at least of shewing their
probable limits.
My object therefore is to communicate the result of calcu-
Jations that I have made, from the data published by Lieut.
Col. Mudge in the Philosophical Transactions : and I hope to
make it appear, that the magnitude of a degree of the meridian,
corresponding to the mean latitude of the arc measured by
this skilful observer, corresponds very exactly with the results
of those other measurements that have been above noticed.
In M. Delambre’s methed nothing is wanting but the sphe-
rical angles, that is to say, the horizontal angles observed,
corrected for spherical error. Moreover, for our purpose, we
have no occasion for the numerical value of the sides of the
series of triangles, but only for their logarithms. ‘Thus the
logarithm
FIGURE OF THE EARTH.
logarithm of the base measured at Clifton, as an arc gives us
that of its sine in feet or in fathoms, so that by means of this
latter logarithm, and the spherical angles of the series of fri-
angles, we obtain at once, and as easily as in plane trigonome-
try, the logarithms of the sines of all their sides in fathoms,
After this, it is extremely easy to convert them into loga-
rithms of chords or of arcs, for the purpose of applying them
to the computation of the arcs on the meridian or azimuths.
I give the preference to taking the logarithms of the sides as
arcs, because the computations become in that case much more
simple and expeditious.
Near to Clifton, which is the northern extremity of the are,
3 ,
7
Reductioaof
the northern
in asituation elevated 35 feet above the level of the sea, a base to toises.
base was measured of 26342,7 feet in length, the chains
being supposed at the temperature of 62° Fahrenheit, or 131°
Reaumur.
_ For reducing this base to toises, we have the proportion of
the English foot to that of France, as 4 : 4,263, so that if p be
taken to express the fractional part of the French foot, corres-
hee to English measure, then log. p=9,97234,40587,
and then log. of 26,342,7 =4,42066,02860,
pics hence the log. of the base in toises will ve found equal to
3,61485,36943, and the number of toises corresponding is
4139,5 taken at the same temperature, which corresponds to
162° of the centigrade thermometer.
This base we must consider as an arc of a circle, and it is
easy to reduce it to the sine of the same arc, according to
the method given in a note at the end of this memcir. The
logarithm of the sine of the base in toises is found to be
3, 61485,35800.
With this quantity as base, and by means of the spherical
triangles given by Lieut, Col. Mudge in his paper, f have found
from which
and the spheri-
cal triangles
the logarithmic sines in toises of all the sides of his series of the portions or
intervals of the
triangles, and have subsequently reduced them to logarithmic ations with
arcs of the same, which enable me to complete the rest of the their azimuths
were compu.
calculation. Withthese we may compute any portions of the
meridian, or successive intervals of different stations expressed
in toises, and in parts of the circle, or their respective azi-
muths,
528
Col. Mudge’s
data,
from which
the computa-
tions were
begun,
and continu-
ed through the .
whole series.
FIGURE OF THE EARTH.
muths, having regard always to the relative convergence of
different meridians,
The author has made observations for determining the lati-
tude of the two extremities of his arc, and has also determined
the azimuths of the exterior sides in his series of triangles by
means of the greatest elongation of the pole star. ;
In the calculations that I have mde, I began at Clifton in
Yorkshire, the northern extremity of the arc, and for this
purpose the following are the data furnished by Lieut. Col.
Mudge.
Latitude of Clifton reduced to the centre of the station 53°
27’ 36,62.
Azimuth of Gringley, seen from Clifton, and reckoned from
the north toward the west 256° 17’ 25’.
Azimuth of Heathersedge. seen from Clifton, and reckoned
in the same direction 118” 8’ 8,81.
With these data, and the two tables of spherical triangles
and the logarithms of their sides expressed in arcs, the inters
vals between Clifton and the two stations Gringley and Hea-
thersedge were found in toises and in seconds of a degree, as
well as all the corrections to be made on the first azimuths
increased by 180°, as azimuths of Clifton seen on the horizon
at these latter places,
The same process was continued for the following stations
in succession, all the way to Dunnose in the Isle of Wight,
which is the southernmost extremity of the series,
In this manner we have the latitudes and azimuths cf each
station, by means of two or three preceding stations, and con-
sequently we have a verification of all the calculations that have
been before made by Lieut. Col. Mudge.
The results of my calculations are contained in the two fol,
owin tables.
First
FIGURE OF THE EARTH. 329
First Table of Distances in Toises and in Seconds of a Degree Table of dis-
on the Meridian, comprised Letween the westerly Stations in tances of the
_ the Series of Triangles.
Names of the Stations.
Clifton -
0,0 0,0
Heathersedge_ - 6834,324 430,9028
Orpit - 15818,489 997 5928
Castlering ” 19801 ,1934 1248,8226
Corley - 14295,384 901 ,6207
Epwell - 22327 ,008 1408 2543
Stow - - 9555,479 602,7284
Whitehorse - 18799,645 1185,8656
Highclere “= 14990,567 045,6354
Dean Hill - 16105 ,614 1016,0180
Dunnose - 235209,886 14844531
Sum total - 162057 ,5437 10221,9837
rcs in toises,
Arcs in Seconds,
westerly sta-
tions on the
Meridian ;—
in toises andia
seconds,
Second Table of successive Intervals between the Eastern Stations. Table of the
intervals
Names of the Stations. Arcs in toises, ArcsinSeconds, between the
E. stations.
Clifton - 0,0 0,0
Gringley « 2809,105 177,149
Sutton = 10838,816 1061,931
Holland Hill 4681,190 ~ 205,2251
' Bardon Hill 18092,261 1141,0462
. Arbury Hill 27956,417 1763 ,2683
Brill - 22374,106 1411,2769
Nuffield ° -14350,3834 905,2155
Bagshot = (121237 ,933 765,6822
- Hindhead : 14449,2027 911,5140
Butser Hill 7853 ,644 405,4551
~Dunnose = 20514,036 1294,1974
Sum total ~ 162057,0941 10221,9607
Now if we take the arithmetic mean of the sums contained The arithmetic
mean of those
jn the two tables, we have for measures of the entire arc, results gives
comprised between the stations of Clifton and Dunnose, the
following quantities 162057,32 toises, and 10221,972 seconds
of a degree, or 2° 50° 21° ,972- :
these by the second, we get the measure of a degree, corres-
ponding to the mean latitude of the whole arc, equal to
the mean
degree 57073
toises, of lat.
By dividing the former of ofthe whole
Ic.
57073,74
330 FIGURE OF THE EARTH.
57073,74 toises,, or 60826,34 fathoms, at the temperature of
162° of the centigrade thermometer, the latitude being 52°
2° 20”. ;
Balaby Asis Thestation at Arbury Hill happens to be very nearly in
arcinto two the meridian of Clifton and Dunnose, and divides the interval
neatly Sa between them into nearly equal parts. The measures of that
RRR mean Patt of the arc, which lies between Arbury and Dunnose, is
deg. proves= by the tables 91679,47 toises, and 9783,34 seconds, or 1° 36°
ri 23,34 of the common division of the circle. The mean Jati-
tude of the arc is 51° 25° 21”. And the measure of 1 degree
corresponding to it is 57068,41 toises.
saiehe In the same manner the measure of the are comprised be-
sepa tween Arbury Hill and the northern extremity at Clifton, is
>” 70377,85 toises, and 4438,63 seconds, or 1°13° 58,63. Its
toises,
mean latitude is 52° 50° 32”. And we have for one degree of
the meridian, corresponding to this latitude, 57080,70 toises.
and the Hence, if we divide the entire arc into two equal parts, we
SPErEES deduce the following values of a degree corresponding to the
increase in
middle of the whole and of its parts.
going
northward,
Latitudes.
51° 25° 20° 570608
52 2 20 57074
52 50 30 57081
in perfect These values are, as appears, perfectly in conformity with
formit .
sich titeory the theory, and with the results of other measures that have
mad coe cents been taken in different parts of the northern hemisphere ; but,
plasty dee in order to place that agreement in a more distinct point of
view, I shall show how nearly these estimates agree with the
elliptic hypothesis, by comparing them with those measures
of a degree, on which we can place the greatest reliance for
exactness.
Inquiry into Now, if we compare the results of these calculations with
the errors those deduced by Lieut. Col. Mudge from his observations, we
which led to aR a EO
the former shall see the probable source of those errors, which it appears
' €onclusionse tome have led him to false conclusions. It has already been
: observed, that the station at Arbury Hill divides the whole
arc into two parts nearly equal, and that it is also nearly in
the meridian of the two extremities at Dunnose and Clifton,
It was, in all probability, this circumstance which determined
the
FIGURE OF THE EARTH. 331
the author to observe the latitude of Arbury Hill, as he would
then have two partial arcs independent of the whole and of each
other.
For determining the angular extent of these arcs, Lieut. Col. ih The
ay: : angular extent
Modge observed the zenith distances of several stars on the rae SORT
meridian above the pole, by means of a large zenith sector observed by
He a _1 Col. Mudge
constructed by Rimsden, with the same pains that he bad va zenitl
bestowed upon the theodolite. Lieut. Col. Mudge paid ail sector ;
possible attention, and took all such precautions as might natu-
rally be expected from an observer of his experience and
address. Nevertheless the results of his observations made in which the
é “ ' , results vary 4
on different stars, differ no less than 4 seconds from each ec.
other. But, by taking a mean of all, the dimensions of the
three arcs reduced to the centre at each station are as follows,
Between Cliftonand Dunnose 2° 50° 23,35 ee RD ih,
Clifton and Arbury 114 3 ,40 servation in
Arbury and Dunnose 1 36 19 ,95 deg. and pts.
The extent of the first arc, in linear measure, is 10363394
feet English, and when this is reduced to toises, we have for
the lengths of the three arcs from Lieut. Col. Mudge’s mea-
sures,
From Clifton to Dunnose 162067,3 The samearcs
; Clifton to Arbury 7038C,2 De
Arbury toDunnose 91687,1
These last values exceed those resulting from my compu-
tations, the first by 10 toises, the second by 2, the third by 8
toises; and these differences arise from the convergence of
the meridians, which the author thought might safely be neg-
lected, and in fact it does not make a difference that is percep-
tible in the value of a degree upon the meridian. For the
difference of 8 toises, in the distance between Dunnose and
Arbury, makes but 5 toises difference in the value of a degree
upon that arc, and the difference of 10 in the whole distance
from Dunnose to Clifton, makes 34 in the measure of each
degree on that arc. So that, as far as this source of disagree- R
. ’ : 7 are not materis
ment is concerned, the author’s results and mine would not ally differing
be found to differ materially from each other, from the com-
puted tables,
But,
532 FIGURE OF THE EARTH.
But, if we attend to the angular dimertsions of the several
arcs, as deduced from observations and from calculation, these
will not be found to agree so nearly.
The following table will shew the differences in each instance,
fe) td wv
But in deg. and Clifton and Dunnose 2 50 23" du Onmerved
pts. they differ 2 50 21 ,97 calculated
very consider-
bly. aie
ae Difference + 1 ,38
i lo 14’ 3”,40 observed
wiht Wot . 13 58 ,63 calculated
= Sd
Difference + 4 ,77
1°36 19,95 observed
1 36 23 ,34 calculated
ed
Arbury and Dunnose
*
Difference — 3 ,39
These differences are really considerable, and are capable
of producing important errors in the results dependent on them.
In the first place we see, that the southernmost are between
Dunnose and Arbury is smaller than it would appear by com-
putation, by as much as 3”,4, and when this deficiency is
combined with an excess of 8 toises in the linear dimensions
- wamely 40 of the same arc, it makes as much as 40 toises difference in
feos 5 the estimated length of a degree. The reverse of this occurs
in the northern portion of the arc comprised between Clifton
and Arbury Hill. This is larger than it ought to be by 4,77,
and hence the value of a degree on the meridian turns out too
The excess of Small by about 62 toises in its linear dimensions. Fortunately
the totalarc is, however, the excess of the total are is extremely small, as it
aa oig does not exceed 1,38, so as to make but 5 or 6 toises differ-:
ence in the length of a degree observed on the meridian, and
corresponding to the mean latitude of the arc examined.
Hence the ap- From what has been above stated, it seems almost beyond a
ae eae: doubt that it is to errors in the observations of latitude, that the
to be ascribed 4Ppearance of progressive augmentation of degress towards the
to error of obs. equator, as represented by Lieut. Col. Mudge in his paper, are
ee ag Arbu- to be ascribed, and that it is especially at the intermediate sta-
tion
RQ
FIGURE OF THE EARTH. $33
tion at Arbury Hill, that the observations of the stars are erro-
neous nearly 5 seconds, notwithstanding the goodness of the
instruments, and the skill and care of the observer. But, before
T insist farther on this head, I will answer one objection that
may be made to the principles of the method that I have pursued
in this Memoir. ‘
Those astronomers, who have hitherto undertaken the mea- Objection. The
surement of degrees of the meridian, have dedaced their Saath n ‘1
measures by simply dividing the linear extent by the number diipticaldeaze,
of degrees and minutes found by observation of the fixed stars are too uncer-
a : 2 CAAA BD tain to be
taken at the two extremities of the arc, This is indeed the employed in
most simple that can be adopted ; and it has the advantage of calculating the
being independent of the elliptic figure of the earth, especially sani ih
in ares of small extent. The elements dependent on this
figure, are too uncertain to be employed in calculating the
anguiar intervals in the short distances between successive
stations, even as a means of verification, without risk*of com-
mitting greater errors than those to which astronomical observa-
tions can be liable. Accordingly one cannot safely make any
use of it in cases where great accuracy is required.
I must admit the justness of this objection, and must there-
fore shew the extent to which it really applies to the present
subject.
In the first place, I may suppose, that in consequence of but, pee -
some fault in the instrument, with respect to vertical position, dif, iericae
construction, or some accidental derangement, there is an give diff. ellip=
error of some seconds in the observations of the fixed stars. Pe Abie Som
How is this to be discovered? This is not to be done by com- ted that the
paring the value of a degree on the meridian, as deduced from _qeagebggee
these observations, with the results of other measurements in ed to the fig of
distant parts of the globe. For if we find that these degrees eds ti
so taken do not agree in giving the same ellipsoid, we are not errors of obs,
to attribute all the differences to irregularities of the earth,
‘without supposing any error on the part of the observer, of his
instrument, or of other means employed in his survey.
But this, in fact, is what has generally been done. It must,
however, be acknowledged, that the majority of observers
have not been in fault, as they could do nothing better ; but’
foo much reliance has been placed on the goodness of their
instruments, their means, and other circumstances, It is true
that
is
2
ree
ON THE ROOTS OF TREES;
that irregularities of the earth and local attractions may o¢ca=
sion considerable discrepancies which are even inevitable ; but
before we decide that these are the real source of disagreement,
we ought carefully to ascertain that there are no others.
(To be continued.)
If.
On the Roots of Trees. By Mrs, Acnes Ispetson.
To W. Nicholson, Esq.
SIR,
Thedifficulties }[ N my last letter, it was my endeavour to give as exact am
Sia account as possible of the increase of trees, both in length
and breadth; that which they made in spring.and autumn, and
that which (nearly at the same time) enlarges the trunks. £
shall now venture on a more difficult task, the delineation of
the root, which I have long delayed ; for whenever I was on
the point of attempting it, I feared I was inadequate to the
undertaking, and put it off another year, till further dissection,
and a more thorough knowledge, should satisfy me that I was
capable of giving an account that would please myself, and do
justice to the great object of my pursuit. For many years to-
gether I have recurred to the subject, studying it with the most
indefatigable industry, and seeking in nature only for informa-
tion: but for the last six months the quantity of roots, both,
fresh and dry, that I have dissected, the innumerable cuttings
that I have subjected to the solar microscope of the roots of
different trees of every age and size—in short, the, endeavours
I have made to collect facts sufficient to prepare myself to
give an exact account of the laws by which the root is regu-
lated—the power which governs it in its exterzor, as well as
anterior form—the parts which compose, and the mechanism
which moves it, has at last given me courage sufficient to ven-=
ture on my task ; and if I do not thoroughly satisfy my readers,
I shall still show many things perfectly unknown ; and, ata
future time, I shall hope to add circumstances that may render
it more complete, and more worthy the attention of the public =
at least I can promise, that I shall advance nothing but what:
all may ascertain the truth of, nor enter into any detail that.
may
ON THE ROOTS OF TREES. 835
may not be proved to be just and true, by those who will take
the trouble of secking, both in dissection and practical garden-
ing, that knowledge, which constant labour and watching has
procured me.
The first thing that strikes the mind with astonishment in Explanation
the dissection of roots, is that excessive motion to which they ah root of
are subject ; each fibre, and each sap-vessel must be capable
of changing its place, and of creeping individually into ano-
ther situation ; and yet so admirably is the tort ensemble con-
irived to make but oe whole, that it rarely differs from that
form and fold, which is allotted to that species of tree. The
root of a tree is that part which is the foundation of the
sap-vessels. I have said, that each sap-vessel of the stem is
joined about two inches above the earth, to two sap-vessels of
the root ; and so wholly and individually do they belong to
each other, that they cannot be divided, without ‘causing the
destruction of both ; the root may, indeed, sometimes shoot
out another sap-vessel, I believe ; but the stem-vessel cannot
shoot (in this situation, and thus aggregated) another root.
This vessel has its little branch, flower, and fruit proportioned
to its size; it is impossible to know what each stem cylinder,
with its accompanying root, will produce, because it cannot be
traced higher in the tree than the trank; but from the root
to that part I have often followed itin one lengthening string.
_ Monsieur de St. Aubert, (who is pursuing the same course of
study as myself,) confirms what I have now written, by dissec-
tions published just after my opinions, in this respect, appeared
in your Journal; and any one that studzes from dissections,
must, I trust, be of the same manner of thinking, the tratl so
plainly appears in them. Totheroot is added many radicles Radicles, with
with all the mechanism necessary to collect and throw up the their mecha-
nourishment procured from the earth around. That every weg
plant has the power, from all the variety of soils and decom-
posed matter, to select that which best suits its nature, and
convey it to the bottom of the root, where all the juices meet,
and are properly compounded and assimilated to the nature of
the plant, is a certain truth: this general reservoir is found
at the part where the root begins ¢o contract, to form the sap-
toot. It is known by the quantity of alburnum laid up there.
T have long been convinced, that alburnuna is the congealed
ws juice
336 ON THE ROOTS OF TREES.
juice into which all the various nourishment o° the earth turns;
part forms into sap, part into the jelly of wood ; for ‘he sap is
nothing but this juice in a dissolved state, and the woo: nothing
more than alburnum, having the wood and bastard vessels
Jengthening by degrees, and running through it. It is im-
possible, that any wood vessels can be formed by this juice, but
the sap may easily be converted into that jelly-like substance,
which forms the alburnum, and the rest of the process may
be seen to pass under your eye in the solar microscope ; that is,
the bastard vessels may be seen to lengthen, and the sap-vessels
to pierce through the softer substance, for the completion of
the wood.
First part of The root may be divided into three parts ; the first part
the root. ieee
shows the difference between the stem and root, the latter
having doutle the numler of wood vessels, and no pith ; for
No pith after after the first three or four years, the pith always disappears in
the turd year. the root of irees, and the line of life occupies the centre in its
stead ; indeed, as the chief use of the pith is to moisten the,
wood vessels, that they may bend in every direction, and thus
facilitate the exit of the buds; and as the roots of trees have
few buds after that time to throw from the root, the pith would
no longer be‘of use in the centre ; the bark and inner bark are
nearly the same as in the stem, and the row of alburnum ra-
ther larger—that the wood should be doud/e in the root, to what
it is in the stem—and that it should increase according to the
increasing branch, is the most absolute proof that the sap flows
in the woud, since no other part would produce nourishment
sufficient to support the tree. But no person who dissects
trees, can doubt this truth, as the immense sap-vessels, and
their being loaded with sap, must carry conviction to the most.
incredulous, provided they see it properly magnified.
The second part of the root is that which appears to be the
reservoir. It has all the parts already mentioned, except that
the bark is narrower, and that the part usually occupied by the:
alburnum, has from three to five rows of that matter, instead
of one; they are wide and juicy, and the quantity most irre-
gular. I have often seen them almost heaped together, forming
at. once from five to seven rows; but I never saw more.
(See fig. 1. Pl. 8.) The alburnum is loose and thin, and far more
watery and unfinished in its appeatance, than in the stem, or»
first
Second part of
the root,
ON THE ROOTS OF TREES,
‘
337
first root. The tap root is the third division—it is of the ut- Third division,
most consequence to attend to the shoots that belong to the
different roots—it is the tap root which always forms the
leading shoot of the tree ; and if it is cut, it will, without
doubt, spoil that part, by forming two middle stems to the tree ;
at least I have generally found this to be the case; and as the
beauty of a tree depends much on the perpendicular height of
its single pillar, the custom they have in most nurseries of cur-
tailing the tap root, is a most vicious one. A row of alburnum
is seldom found in this part of the root; for it increases this
way but once in seven or eight years—its growth is, indeed,
in a different manner, shooting from the end; for if Isever the
smallest piece from the tap-root, it will very soon throw out
two ends, and if these are cut, two more will be added to each,
and it then ceases to shoot perpendicularly ; losing its form,
and then growing like a common root, whereas a tap-root draws
out at the end like a telescope, one inch each shoot; and if it
is dissected with care, two or three of these divisions will be
found. What is the use of the tap-root ? . By shooting per-
*pendicularly down, to fix the tree firmly in the ground, and
Keep it straight in that position ; then it is surrounded by ra-
dicles which perpetually pump up from every different soil, as
it proceeds in depth, what other roots cannot attain, matter
which, mixed with what the higher grounds bestow, serves to
bring a variety to compound the different ingredients required
for the various nourishment of the tree, probably minerals are
wanted to form the juices of the ark; and I doubt not that
the deep descent of the tap-root is most necessary to tne health
and vigour of the tree. How improper, then, is the custom
of cutting it, and curtailing also many of the other roots, each
of which has its appropriate branch, which will, of course,
suffer in decay for the delapidations produced by the ignorance
of the gardener. But the loss of the tap-root can never be
remedied. It can no longer serve as a deep well, to gain not
only a quantity of moisture from the number of rills it may
meet with in its descent, but also matter from a variety of soil,
and innumerable productions it passes in its way. The tap-root
is, then, like the radicles, only a larger pump to collect and.
or tap-root.
Use of the tap-
roct.
Never to crt
the roots.
throw up all that it can select of water and other juices. The |
second part of the root is the reservoir for coliecting the mate-
SupPLEMENT.—VOL. XXXIV. No-156. Z rials
$38 ON THE ROOTS OF TREKS.
rials; and the third part is the laboratory for forming eath
different gas and juice necessary to the health and habits of the
tree. I may welladda fourth ; for the radicles are the col-
lectors sent out on every side to seek fresh provisions, to gug-
ment the stores, and increase the riches of this little habitation.
Defect of cut- They have all the mechanism appropriated tothe purpose, and
i ui ‘@P- the bark and rind are so joined, as to serve, not only to protect
and defend them from the stones and insects within the earth,
but also to pierce and make way for them through the hardest
materials ; for they possess that softening power which enables
them, I may say, to eat their way into every substance. It
The Ney cannot be doubted, that they possess this faculty as well as
buds, since I have perpetually found them dividing roots, pierc-
ing through the hardest wood, and even separating stones where
Root to be cut any little defect assisted them. That a tap-root, or any root
if injured. that is injured, should be cut off, there can be no doubt, since
the danger of the rot is greater than any other inconvenience—
but the greatest care (when trees are to be transplanted) should
be taken not to hurt the roots, and if any radicles can be pre-
served, by wrapping them upin fresh earth, it should be done ;
for if they will live a little time, it will le a great gain to the
-Netessity of tree ; and here is the advantage of having the pit ready dug,
removing trees and removing the plant, with all the earth around it—it pre-
quickly. d : :
serves the few radicles alive, and enables them directly to per-
form their office of pumping moisture and nourishment from
the earth—but if the tree is taken out some hours before it is
replaced, all the radicles are sure to die ; and if the tap-root is
also injured, no wonder they never make fine trees; or that
those planted by nature are always found superior. The reason
that throwing a quantity of water into the pit has been found
serviceable, is, that it supplies moisture, and quickens the
growth of the new radicles; and what is still more advantageous,
and should be constantly done, a large barrow of good mould
should be thrown on the roots, and about the radicles; for a
young and tender shoot, if it has to pierce through clods of
earth in its sickly state, will certainly fail. It is like easily di-
gested meat to a weak stomach—if you load it with heavy food
at first, it destroys itat once ; but let it gain strength and vi-
gour, and a well-conditioned radicle will pierce through. stone
walls in time. It may be supporer that according to the va-
, riet MM
ON TIIE ROOTS OF TREES.
riety required to compound the juices of the tree, such is
the depth or shallowness of the root. The oak and ash are
two of the deepest rooted of our forest trees, and should not,
therefore, be planted close together—they may injure by inter-
secting each others roots—indeed, the greatest care should be
taken, that even trees of the same kind (much more if they
are not so) should not shoot their branches so as to cross or lie
oneach other, It is inconceivable the mischief they do, whe-
ther root or stem branch—in the first, itis not so easy to guard
against the evil ; but at their original planting, great care should
be taken to place their roots regularly and even in the ground,
and not allow them to cross, in which case nature herself, with
the utmost diligence, will avoid another root’s covering them.
But it sometimes happens both above and underground—and
in the first, when seen, it should directly be remedied, for no-
thing brings the rotso soon. They either both contract into
so small a compass as to injure each other, or one gets the
better and destroys the other, or the dispute carries the rot into
both—for they will not continue to lie one on the other, with-
out receiving, or doing injury: but, first losing bark and rind,
the upper one, pressing on the other, in a few years pierces it,
and then the trial of strength begins between each separate set
of the sap-vessels. I have some curious specimens of this
kind, well worthy being presented to the public attention, as
giving a thorough insight into the nature of a tree, and as ad-
mirably pointing out the consequential-parts of a plant, which,
of course, are always the last to give way.
T shall now turn to the manner in which the roots of trees
are folded (if I may so express myself) in most forest trees,
such as the elm, the oak, the ash, &c. They are laid exactly
like a circular fan, their folds meeting in the centre, and appa-
rently doubled over at the bark. ‘his is admirably seen in
“the oak, stijl better in the lime tree : but most visibleina
good double microscope—and so excessive is their predilection
for this shape, that cut them ever so straight, nay, plane them
smocth, and in a few hours (if the wood retains any vigour of
muscle) the ribs will again evidently appear to be rising, and
the finger which passes over, will be able to mark its motion,
-or at least will feel the height the muscles have gained. In
some roots I have measured the rising, and found it to be above
Z2 the
$39
Not to crosa
their roots,
and not to
cross stem
branches.
Various folds
of the root.
340:
Folds caused
by the muscu-
lar. fibre.
Spiral wire
which causes
it.
@©N THE ROOTS OF TREES.
the tenth of an inch in twenty-four hours. Think what it
must be in fresh and living plants! See the different sorts of
figures into which the oak, &c. folds from that of the firs, The
first fig. 2. BB, the second fig. 3. CC. showing it more plainly
than in the circle. Let not the reader suppose, that this is
the common warping of wood; it is the regular fold, always in,
one figure, and which goes off long before the wood is dry, and
only retains it, ike the animal muscles, a little while after life
has ceased to linger in it. It is the last power of the muscular
fibre of the wood, or rather of the spiral wire. I have not yet
mentioned this as forming part of the root, because it does not
(as in the stem) occupy a separate division in surrounding the
nearest sap-vessels to the vital part. But in the wood of the
root it circulates round every sap-vessel; separating each cylin-
der of wood, and meandering on z¢ from one sap-vessel to ano-
ther. (See fig.4.) | Besides penciling out the folds in three
distinct rows of spiral wires, in each yearly increase, as at fig.
5. I doubt not, therefore, that it is the sptral wire which
causes this peculiar motion, and I am the more persuaded of
it, because, though the motion of the firs acts in such a reverse
manner, yet the spiral wire accompanies it, so as equally to
affect the motion, though in a perfectly different direction.
What, then, can be said against the spiral wire being the cause
of all motion in plants? The more I see of vegetable life,
the more I am convinced of this reality. * From the first I _
trusted to nature to prove her own truths; and she will do it,
~ because I am most careful never to make one for her. The
No tap-root
in firs.
spiral wire never retains its power of motion above thirty-four
hours after it is taken froma plant, and it is nearly the same
with the root. I shall now indicate the extreme difference
observed in the roots of firs, when compared with that part
in other trees. [must beg Pliny’s pardon for detecting him
in an error when he says, “ that he saw a fir tree planted, whose
tap-root measured twelve feet.” Now unfortunately, no fir
lias any tap-root. Such is the aversion their roots have te
piercing the earth, that in young trees they will frequently be
found with their roots bent back, and thus forming a hook or
loop. (See fig.6.) The roots of the Weymouth pine and sil-
ver fir, generally divide into ¢hrees, and run an amazing way
horizontally under ground; but the Scotch and Spruce firs run
ye)
ON THE ROOTS OF TREES. SAI
in every direction, and a very little depth for such large and
high trees. The division of the root, indeed, takes place in all
the firs much higher in the stem than in other trees., None of
the firs have any reservoir of alburnum, as is found in the se-
cond part of the root of the oak, &c. or I have not yet been
able to discover it, from their not having a tap-root to guide me
in the search ; but I shall look more carefully. I have, how- Dissected
ever, dissected more than four dozen fir trees of all ages and ™ny fs.
sizes, growing naturally, and transplanted, not only in seeking
that, but the tap-root also, but in neither have I succeeded.
The tap-root in other trees, though, from being removed, it
has branched and lost its shape, yet is always known ; and so
it would be in the firs, I doubt not, f they had any. But in
all I have seen, there is not the smallest appearance of one, and
if one of the side roots has been by accident turned down, its
increased shape, on one side, shows that it was originally a side
- Toot forced into another situation—yet the eract Evelin also is
mistaken. There is some variation in the bark and rind—they Bark and rind
are not exactly like those of the stem. At first I thought they eae me
were not composed of leaves, as the coverings of the trunk of
all firs are (see my letter on the subject in your Journal,
33 ;) but that was undoubtedly my mistake—they are formed
of leaves, but thinner than the stem. The greatest part of the
bark division is engrossed by that curious matter which sepa-
rates the inner bark from the alburnum, and even in old roots
is discovered to be of the most silvery whiteness ; and its situa-
tion has so changed its very nature, that, instead of a thin divi-
sion of hard rough wood, it appears like the most beautiful
soft white leather. Surely its changing thus must show the
excéssive power of the juices of the firs in softening and tan-
ning leather, and its vast superiority over the oak bark, or that Superiority of
of any other tree now made use of for the purpose—for though He ai es
the oak has a very thin layer of this same matter to keep the :
debilitating juices from the wood, it is not softened and emo-
licated by its liquid, nor has it attained any thing like the sup-
pleness or delicacy of that which encloses the fir, (as all may
see that examine it) though they are both woods originally of
nearly the same degree of roughness and hardness, I most wish that
sincerely wish that Sir H. Davy, or his brother, would turn their some chemist
attention to this subject—it is very unlikely that nature would acca eating
give
342 ON THE ROOTS OF TREES.
give such a proof of this, if it was not thoroughly worthy the
strictest attention. I have not yet described ai] the motion
~ that belongs to wood inthe roots : as this is equally found in
firs as in all forest trees, I have retained it as the last explana-
tion, It is inconceivable what alteration two inches, or even one,
will sometimes produce in a piece of root. I have seen the
pith change its place two or three times in as many inches. I
have now a piece by me where all the ovals are within one
another, and of sixty in number, change in less than three
inches in length to three regular circles, each circle bearing
interlacing figures of fifty-nine each. Conceive what must be
the motion of wood, that would, inso short a space, produce
such a revolution of form and figure ! it was only in tracing
each sap-vessel in length, that 1 could persuade myself of the
reality ; the stems of trees are infinitely more quiet in_ this
respect, and generally retain the pith at the same side, unless
some cause, such as rot,or any injury happening to force a
change. Butitis very different in the root; that perpetual
motion appears necessary to it is certain, and I doubt not con-
tributes to its health ; and, by seeking further, we may be the
means of deyeloping many of the disorders of wood. How
often we find, that laying the earth lighter on the roots gives
Knowledge of fresh vigour to the tree: this knowledge of its motion will
ike oleae °f open a source of refreshment of great consequence, I should
ies hope, to their general health. In short, the more we are ac-
quainted with their inward structure, the more we shall be
able to administer to their diseases. In this situation it may
be compared to the advice given in a surgical case by a person
a proficient in anatomy, and one wholly ignorant of it—he who
is best acquainted with the formation is more likely to hit on
of use in gar- the real disorder. May we not, therefore, hope, that, by gain-
dening. ing a thorough knowledge of the interior of plants, it may, in
‘ time, lead us to an acquaintance with their diseases, and give
us some notion how to remedy them. I am collecting a set
of specimens to show the different disorders in trees and their
causes ; and when J am adyanced enough, shall lay them before
the public. hie
I am, Sir,
Your obliged Servant,
AGNES IBBETSON.
The
ON THE ROOTS OF TREES.
The roots of fruit trees, herbaceous and annual plants, will
“be given in my next letter.
References to the Engraving, Plate VIII.
Fig. 1. View of the five rows of alburnum found in the
second part of the root.
Fig, 2. View of the sort of folding of the oak and all forest
trees. Whether the shape of the wood be circular, oval, or
any other shape, it always folds in this manner.
Fig, 3. View of the manner of folding of the firs: it all
joins underneath, though so much doubled under.
Fig. 4. View of the piece of wood showing the spiral wire
running round the sap-vessels as it doesin every slender cylin-
der of the wood. They are so thin, that more than 150 may
go to an inch in length.
Fig. 5. Vhe wood showing the penciling of the folds by the
spiral wire on the oak.
Fig. 6, The hook of a young root of fir.
Fig. 7. The root of the Weymouth pine reduced.
Great care should be taken, if the tree must come from the
nurseries, not to plant them too old. It is astonishing, when
you dissect wood, what a difference there is between wood thus
planted, and wood never removed and growing from the seed ;
there is a regularity in the latter, an evenness of grain ; particu-
larly if it is all the same degree of hardness ; not a piece almost
iron in one place, and perfectly soft in another ; it is all equally
firm and solid. But I have repeatedly found in trees planted,
large alternate layers of hard and soft wood, that must make it
almost useless to the carpenter. There is also another defect,
which arises from allowing people to cut off large branches
from trees : the piece thus exposed will either decay and get
the rot, or will grow as hard as stone in the middle, while all
the circular part will be as soft as pith : if, therefore, three or
four large branches are cut from a fine oak, at ever such a dis-
tance of time, it will render that tree extremely inferior, in
point of wood, to that which never lost a large branch. If a
branch grows too low, it should be cut off at first shooting,
- when it can have no bad effect. There is not in nature any
thing which deceives so much, as buying trees while sianding,
unless the person is very knowing in wood, so various are the,
hidden
Cs3
344 ON LIGHT.
hidden and conceaied infirmities they are filled with, that, till
sawn out into boards, the juice is not to be known, and the
wisest may be taken in.
Se
Tit,
Popular Statement of the leautiful experiments of Malus, in
which he has developed a new property of light.*
A solar ray is ET a solar ray be directed by means of a beliostat into the
vers in the plane of the meridian, so that it shall form with the ho-
aye : ' y ; é
a an dniile rizon an angle of 19° 10°. Then fix a glass, not silvered, in
of 19° 10’ with such a manner, that it shall reflect this ray vertically down-
the horizon ;
iisthen ree Wards. If below this glass a second glass be placed, exactly
flected by a parallel to the former, the latter will make, with the descending
Be 210s: Der ray an angle of 35° 25’, and reflect it again parailel to its first
pendicularly : :
down:—and direction. Jn this case, nothing remarkable is observed.
ae whe But if this second glass be turned, with its face directed to-
1)
glass, so as to wards the east or west, but without altering its inclination with
pass with the respect to the vertical ray, it will no longer reflect a single par-
same inclina-
tion te the ho. Hele Ghlioht, neither from its first nor its second surface.
bts ma And if with the same inclination preserved with regard to the
t = ‘ : 4 : 3
ee vertical ray, the face be turned towards the south, it will begin
pens if the ray to reflect again the usual proportion of incidental light.
eS jars In the intermediate positions, the reflection will be more or
S. Butif.E.or less complete, accordingly as the reflected ray approaches more
W. the second
glass reflects i
nolight atall. Under these circumstances, where the reflected ray comports
itself so differently, it nevertheless constanily preserves the same
inclination with regard to the incidental ray.
We, therefore, in this instance see, that a vertical rav of light
falling on a transparent body, acts in the same manner when its
reflecting face is turned towards the north orthe swuth, and in
a different manner when this face is turned towards the east or
the west ; although these faces still continue to form, with the
vertical direction of this ray, an angle of 35° 25.
or less the plane of the meridian.
* See also Philos, Journal, XXX, 95, 161. 192,
These
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ON LIGHT. 345
These observations lead us to conclude, that light acquires, Light thus
under these circumstances, properties independent of its diree- SH HON
tion, with regard to the surface which reflects it, but exclusively to the sides of
relative to the sides of the vertical ray, which are here the same the ray.
for the north and south sides of the ray, but different with re-
gardto the east and west sides.
By giving to these sides the name of poles, Malus has given Modification,
the name of polarisation, to that modification which imparts vale
properties to light, which are relative to these poles. And he risation,
says, that he has hesitated to admit of that term in the de-
scription of the natural effects now under consideration, until
the variety of the phenomena obliged him to make use of it.
Let us again, says he, consider the apparatus of which we The light
have been speaking. If to the solar ray which has passed irda
through the first glass, and of which a part has been reflected, first glass is
asilvered glass be presented, which shall reflect it perpen- oe dif-
dicularly downwards, a second vertical ray will be obtained, :
which has properties similar to the first, but in a directly oppo-
site manner.
If a glass be presented to this ray, forming with its direction py. reflection
an angle of 35° 25, and if, without changing this inclination, will be much
its faces be alternately turned towards the north and south, east cone
and west, the following phenomena will be observed. There faces north or
will always be a certain quantity of light reflected by the second 84th»
glass, but this quantity will be much less when the faces are
turned towards the north and south, than when they are turned
towards the east and west.
In the first vertical ray, exactly the contrary may be observed. whichis di
The minimum of reflected ligitt took place when the second re ehie hae
glass was turned towards the east or the west. Thus, in abstract- pens with the
ing from the second ray the quantity of light which comports “eh vertical
itself like a common ray, and which is reflected equally under -
both circumstances, it will be seen, that this ray contains ano-
ther portion of light, which is polarised in a manner exactly
contrary to that of the vertical ray reflected by the first glass.
In this experiment a silvered mirror was used, merely iD The silvered
order to dispose the two rays parallel to each other, and under glass is ps Tes
the same circumstances, in order to render the explanation more Poe hile cate
clear. The action of metallic surfaces being very weak with on the polari-
tion e
regard *
346
Statement of
the effect in
general terms.
The rays re-
ceive the same
modi€céation
as by the douse
ble refracton.
Iceland spar
used to distin-
guish the con.
dition of the
transmitted
yays.
Statement of
the effect as
shewn by the
chrystal.
ON LIGHT.
regard to the polarisation of the direct ray, their influence may.
be neglected.
This phenomenon in the last analysis may. be explained in
the following manner: _ Ifa ray of light fall on a plate of glass,
and form wiih it an incidence of 35° 25’, all the Nght which
it reflects is polarised in one direction or manner, And the
light which passes thraugh the glass is composed, first, of a,
quantity of light polarised in a direction or manner contrary to
that which was reflected, and having a proportion to that quan-
tity, and secondly, of another portion not modified, but which
preserves the characters of direct light.
These polarised rays have precisely all the properties of those
which are modified by the crystals which have double refraction;
and, accordingly, what the author has said of them elsewhere
may be applied withont restriction tothe former.
The author, by continuing his experiments on the polarisa-
tion of light, has observed the following facts :
I consider, says he, in order to fix the ideas, a vertical ray as
polarised with regard tothe plane of the meridian, andJ place
beneath this ray a glass, not silvered, in such a manner, that it
can be turned round upon the ray so_as constantly to make
with its direction an angle of 35° 25°, In order to analyse the
light which is transmitted through this glass in its different po-
sitions, I place beneath it a rhomboid of Iceland spar, directing
its principal section in the plane of the meridian. I shall call
the plane of incidence that which passes through the vertical
incident ray and the ray reflected by the glass.
The ray presents different phenomena according to the mo-
tions or positions given tothe glass itself. When the glass has
made a quarter of a revolution, it no longer reflects a single
particle of light, and the ray that it transmits to the lower
crystal is refracted in the usual manner ; and, subsequently, the
reflected light diminishes, and the refracted light increases, from
the first position of the glass, until the plane of incidence has
described an are of gO degrees. ‘The ray refracted in the ordi-
nary way by the rhomboid, also increases from the former unto
the latter position ; but the extraordinary ray only increases
until the plane of incidence has arrived at an angle of 45 de-
grees. Itis then diminished, and becomes nothing when the
glass has performed one quarter of a revolution. Supposing,
then,
ON LIGHT. BAT
then, that the glass makes one entire revolution, the reflected
light will have two maxima answering tothe positions N, and
S. and two absolute minima answering to the positions E. and
W. The transmitted light, and that which is refracted in the
ordinary manner by the rhomboid, have two minima answering
to the positions N. and S. and two maxima answering to the
positions E. and W. but the light refracted extraordinarily has
four absolute minima answering to the positions N.S. E.and
W. and four mazima answering to the positions NW. SE, NE,
and SW,
In the place of the moveable glass, but under exactly the A metallic _
same circumstances, let a metallic mirror be substitnted, Teena a Sh
which the plane or incidence constantly makes an angle of 45° of the second
“with that of the meridian. When this mirror is inclined only glass.
a few degrees with regard tothe horizon, the light which it
reflects is entirely polarised, like the incident light with regard It polarises the
to the plane of the meridian. If the inclination be augmented, peat 4
it reflects, first, a certain quantity of light polarised with regard ations, govern-
to the plane of the meridian; secondly, another_quantity Ee ky
light polarised with regard to the plane of incidence ; and, 2
Jastly, a certain inclination may be attained, by which the light
is completely polarised with regard to the plane of incidence.
Beyond this limit, the light polarised with regard to thé plane
of the meridian begins to reappear, and the intensity of the
light polarised with regard to the plain of incidence, diminishes
until the mirror becomes vertical. Metallic bodies act, there-
fore, exactly in the same manner as transparent bodies on the
light which they reflect; but transparent bodies totally trans-
mit the light which they polarise in one direction or manner,
and reflect that which is polarised in a contrary manner, while
metallic bodies reflect the light which they have polarised in
both directions or manners.
The facts contained in this memoir point out the methods to
be followed, in order to obtain, in the different cases, an exact
measure of the phenomena. They resolve all that is proble-
matical in this theory, and establish, ina decided manner, the
following consequences—
That all bodies in nature, without exception, polarise com- All bodies po-
pletely the light which they reflect under a determined angle. ee oe te
eh ‘Dat is governed by
848 CONCERNING THE TEAK TREE.
angles of re- That within and beyond this angle the light receives this modifi-
Sabha pecu- cation in a less complete manner.
ae re ie Polished metallic bodies, which reflect more Jight than trans-
to the reflect- parent bodies, do also polarise it in a greater degree. This mo-
i cn dification is essential to the forces which produce reflection.
Allthe bypo- —_ Lastly, these new phenomena have advanced us one step
cia saa nearer the truth, by confirming the insufficiency of all the hy-
Paes insuf- potheses which philosophers have formed in order to explain
ficient. the reflection of light. For example, it is certain, that not one
of them tend to explain, why the most intense ray of light,
when it is polarised, can, under a certain inclination, pass through
a transparent body, and be totally deprived of the partial re-
flection to which ordinary light is subject.
IV,
Some Account of the Teak Tree of the East Indies, By Dr.
WittiAM RoxpureH.
Intiadeccon "HE durability of Teak wood for ship-building is well
known to every one in India, and its qualities are so much
valued in England, that considerable quantities are imported,
The Society for Encouragement of Arts, from whose 30th
volume the following paper is extracted, express their opinion,
that this tree may be successfully cultivated in our West Indian
and African settlements. And though it must be admitted,
that the true national policy of an empire must ever be to esta-
blish those public resources which are least subject to thecontin-
gent events arising from the local distance of colonies, and con-
sequently, that our great efforts ought to be to encourage the
growth of native oak ; yet it must be nevertheless admitted,
that every possible means of insuring our supplies, and encou-
raging our settlements, ought to be adopted.
ae ET
The timber of the teak tree is in India what oak is in Eng-
Great value of ANE ,
the teak tree land; it is, however, unnecessary to enlarge on their compa-
apts East _rative value, because oak will not grow in India: our attention
saney ought, therefore, to be confined to teak alone, not only as being
E by
CONCERNING THE ‘TEAK TREE.
by far the best. wood we yet know. of in this country for ship-
building, but also for the house-carpenter, and almost every
other work where strong, durable, easily-wrovght, light wood
is required. The advantages to be derived from the cultivation
of so valuable a tree, where nature has not bestowed it, must
therefore be obvious to every one ; particularly in Bengal,
where it grows well, and the demand is so great. The teak
tree is a native of Pegu.
349 .
Government, sensible of what is here stated, have long given Encouraged
every possible encouragement for an extensive propagation. by govern-
But to render it still more general, the native land-holders must
be made sensible of the advantages they may expect to derive
from large plantations thereof.
ment.
The growth of the tree is rapid, and at all ages the wood Its growth is
(from various experiments) appears excellent. Some trees in
the Honourable Company’s Botanic Garden, brought from the
Rajabmundry Circar in 1787, were, in 1804, from three to
upwards of four feet in girth, at three and a half feet above
ground, and high in proportion*, These plants were about
twelve months old when sent from the coast, so that their pre-.
sent age is about seventeen years. A tree promising so much
advantage in so short a space, compared to what the oak re-
quires in England to become serviceable in the marine yard,
makes it highly worthy of every attention and encouragement.
A few observations on rearing the plants from the seed seem
necessary, as I have often known seeds from the same tree suc-
. ceed with one person, and totally fail with another.
rapid.
The nut in which the seeds are lodged, is exceeding hard, Seeds, and
manner of
planting, &c.
contains four cells, and in each is lodged a single small seed.
It has been ascertained, that they perfectly retain their vege-
tating power in the growth, even as far as eighteen months ;
however, it is advisable to sow them about the beginning of the
first periodical rains, or north-westers, after they are taken ripe
* The largest of those trees measured, atthree feet anda half above
the ground, in February, 1796, forty-two inches in circumference. The
same tree was, in February, 1804, fifty-two inches in circumference-at
the same place, which gives an annual increase of one inch and a quar-
ter. However, while the trees are younger, and in a more favourable’
soil than where this tree stands, their yearly growth is from two to
three inches, which is fully double the increase of oak in England.
from
Appearance of
the plants.
‘Time of trans-
planting.
Considerations
rela ing to the
proper soil,
CONCERNING THE TEAK TREE.
from the tree in October. If sown about this period, or rather
before than after, in well-shaded beds, about an inch asunder,
and covered with about a quarter of an inch of earth, with a
little rotton straw or grass spread over the earth, to’ keep the
beds in an uniform state of humidity, by gentle waterings,
should the weather prove dry; most of the nuts will be found
to produce from one to four plants, in from four to eight weeks.
However, it sometimes happens, that many will remain in the
ground until the commencement of the second rains, nay even
of the third ; however, this is rare, yet it will be adviseable to
sow the seed on a spot that can be spared, at least until the
rains of the second season are well advanced ; by not attending
to this circumstance, many have thought the seed bad, conse-
quently caused the ground to be dug up for other purposes.
The plants, when they first make their appearance, are very
small, scarce so large as a cabbage plant when it first springs
from the earth ; their growthis, however, rapid. When they
are about one or two inches high, they ought to be transplanted
into other beds, at the distance of about six inches from each
other, there to remain until the beginning of the next year’s
rains, when they are to be planted out to where they are to re-
main, or they may, when from two to four inches high, be
planted out at once to where they are to grow ; and it is not
perfectly clear but by so doing they succeed better ; as in tak-
ing up plants of any considerable size, say from one to two or
more feet high, the roots are very apt to be injured, particu-
larly the sap root, which retards their growth much, nay often
kills them, .
About Caleutta they thrive luxuriantly in most places where
they have been tried, and any tolerable degree of care taken of
them; so that the only observations which seem necessary to
be made on this head, are to avoid sowing the seed, or planting
i such places as are low, or subject to be inundated ; to keep
them ciear from weeds, and sparingly watered during dry wea-
ther, for the first year only. Ina good soil, not mach overrun
with that coarse, white-flowered grass, called by the natives
Woola (Saccharum,) they will scarce require any care what-
ever after the first six months, from the time of being planted
eut where they are to stand. They will then be about eighteen
months old, supposing them to have been transplanted twice ;
: and
ne
Gry
Py
CONCERNING THE TEAK TREE. 3
and in that time they will, in general, be from five to ten feet
high, according as the soil is favourable, and out of all danger,
except from north-westers. _
With respect to the distance at which plants ought to stand ie me
in plantations, every one’s judgment can direct. The cak re- ioliss aieatet
quires a great space, asthe crooked parts thereof are the most
valuable, and’ required for the knees and other curved timber
in ship~building ; but teak is naturally a straight-grained, tree,
and only used in Bengal, or at least in general, for the straight
work, Sissoo being commonly employed for knees and other
crooked timber ; hence it may be concluded, that the straighter
the teak trees grow, the nsore eligible for every purpose for
which this timber is generally employed in Bengal. They do
not, therefore, require to be planted at a great distance, suppose
from six to ten feet, in quincunx order; by being so close
they grow straighter, and protect one another while young,
which is particularly wanted where violent gusts of wind, such
as our north-westers, prevail, y When the trees grow up, they
can be thinned out to advantage, as the timber of the young
trees will answer for a variety of uses. - The seed of this tree
we have now in such abundance, as to render a few hundred
plants, in the hundred biggahs, of little or no importance ; and ’
if the ground on which they are planted is not of the best sort,
the more necessity there is for planting close.
Suppose the trees planted in quincunx order, eight feet asun-
der, a Bengal biggah (which I believe is generally reckoned a
square of one hundred and twenty feet) will hold about three
hundred and ten trees.
-It willbe necessary, during the first ten vears, to cut GOWN pyrticwar die
about half of them, say one hundred and seventy, to give the be eae
rest more room ; they are worth one rapee each. shoe im;
Again, at from ten to twenty years, reckon half (eighty-five) &c.
of the remaining one hundred and seventy to be cut down, to
make stil] more room for the rest, they will be worth four ra-
es each.
And agaia, at from twenty to twenty-five years, it may be
‘mecessary to thin them still more, say to another half, (or one-
eighth of the original number) which will be worth eight ru-
peeseach. The remaining forty-two trees, when full grown,
say in thirty years, may be expected to hare, on an average,
shafts
°
Value of the
produce,
Reduction of
rent, ex-
pences, &c,
CONCERNING THE TEAK TREE.
shafts or trunks thirty feet long, and at least four feet in cireum-
ference, which gives, according. to the bases of timber mer-
chants’ measurement, a girth or square of twelve inches. The
dimensions of such a piece of timber will therefore be thirty
square feet, or three quarters of a ton, which, at one'rupee (or
about two shillings and sixpence sterling) per square foot, the
average price of Pegu teak in this place (Calcutta) for some
time past, will amount to’ thirty rupees per tree. Nor is it
likely that the price of this indispensable commodity will fall ;
our growing trade, and consequent increase of shipping, gives
reason to think it will rather rise in price. Let us, however,
be on the safe side, and say, that each of the last-mentioned
forty-two trees will be worth only twenty rupees each.
From the above statement, the value of a biggah of land,
planted with teak trees, will produce, during thirty years, as
follows :
Rupees.
In the first ten years 170 are cut, and reckoned to be
worth one rupee each, is - - 7 7 lgo
In the next ten years 85 more are cut, and worth four
rupees each, is - - - ~ - - 340
In the next following five years 43 more are cut, and
worth eight rupees each, is = - - - = 344
At the end of thirty years, the remaining 42 trees are
reckoned worth 20 rupees each, is - - - ‘840
Total produce at the end of thirty years - = = 1604
Independent of the branches, many of the largest of which
will be fit for knees, and other crooked timbers, of small dimen-
sions, consequently of considerable value.
From the above sam of 1094 rupees is to be deducted the
rent of land for the before-stated time, together with the ex-
pence of planting, hedging, and taking care of the young
plants during the first few years; after that they will require’
little or no care,
Rupees,
The former let us suppose to be three rupees the biggah,
» which is certainly an high rent, and will amount, in
thirty years, to - - - - - - go
Charges of planting and hedging, say - - - 20
Wages
CONCERNING THE TEAK TREE. - 353
Wages of one man, per biggah, which is fully sufficient,
for the first five years, at 36 rupees yearly - 2 #980
For the next twenty-five years, allow one man to three
_ biggahs, is for one biggah twelve cones or fot twen- | °
fiveyears - = - - - - - ~ 300
Total charges of one biggah for thirty-five years *~ 59C
Deducted from rupees 1694, leaves‘a clear profit of - ° + 1104
Potatoes, leguminous, aod culinary plants, meliorating: crops, The ground
may, with advantage to the plantation*, be reared: ‘in constant oul ‘be profi
succession, on the same ground, during the first two or three vated, and
years, or until the tops of the trees are too large to admit dle advan-
theirgrowth. The produce thereof will help to defray the nies: pai.
expence of labouring the ground during that period ; afterwards,
as already observed, little more will be required than keeping
up a fence round the plantation, to keep cattle and idle people
from hurting the trees, till they are so large as to be out of all
danger.
A period of thirty yeats is only brought into the foregoing ‘phe observa-
calculation, though it may well be imagined, that when in a tionsrelate to
healthy state, they must continue-to gain considerably, both in ii
size and quality, for a much longer period. In the Bath Pa- Subsequent
pers on Agriculture and Planting, Vol. 7, Article 1, Letter the de tow!
Fourth, a “Btigle oak tree is traced to have taken seventy-five profit,
years in acquiring a single ton ; whereas in another seventy-
five years, the same tree gave seven times as much in quantity,
besides the increase in value as naval timber.
_ In addition to the remarks already made, it may be proper’ to
add the following extract of a letter from Thomas Barnet, Esq.
to G. H. Barlow, Esq: Chief Secretary to the Government,
dated 8th November, 1799.
«« A few years ago, a numberof teak tree plants were, by
* About six years ago my gardener trenched a piece of useless ground
behind some cottages,and planted it with'refuseelm suckers; thus prepar-
ed, the poor people availed themselves of the circumstance,set the ground
with beans and potatoes, and have continued to crop it ever since; this
has been of service to them, and of infinite benefit to the trees, which,
by means of this annual culture, have outstript their undisturbed bre-
thren, and almost doubted their contents. Bath Puper, Vol, 6, p. 17.
SurrLement.—Vou. XXXII, No. 155. Aa erders
354 ‘SULPHUR AND PHOSPHORUS.
‘© orders of Government, I believe, disseminated in different,
*¢ parts of the country, for the propagation of teak timber.
« Amongst others, a few plants were sent to Rampore Bau-.
€¢ leah ; this wasin 1795. These plants have throve in a sur-
‘< prising manner, and are, at this time, between twenty and
“ thirty feet high, and near a foot in diameter ; the wood of
“« the hardest kind, and, as far as can be judged at present,
“« greatly superior to the teak of Pegu.” —
\ WILLIAM ROXBURGH.
Calcutta. '
To C.. Taylor, M. D, Sec.
fp Se RIS SS
Vv.
On some Combinations of Phosphorus and Sulphur, and on:
some other Subjects of Chemical Inquiry. By Sir Humpury
Davy, Knt. LL. D. Sec. B.S. |
1. Introduction.
Thee aeths N this paper I shall do myself the honour of laying before
aan the Society the results of some experiments on phosphorus
and sulphur and sulphur, which establish the existence of some new com-:
establish the pounds, and which offer decided evidences in favour of an idea’
notions of de- :
finite propor- tha‘ has been for some time prevalent amongst many enlight-
ee com- ened chemists, and which I have defended in former papers
inations, &c. : ‘ i i ‘ r
published in the Philosophical Transactions ; namely, that
bodies unite in definite proportions, and that there is a relation
betweer. the quantities in which the same element unites with
different elements.
I shall not enter into a minute detail of the methods of ex
perimenting that I employed ; I shall confine myself to géneral
statements of the facts. Thecommon manipulations of che-
mistry are now too well known to require any new illustra-
tions : and to dwell upon familiar operations, would be to
occupy unnecessarily and tediously the time of this Jearned
body. | :
2. Of some Combinations of Phosphorus.
Two distinct — Ina paper read before the Royal Society in 1810, I have
de-
SULPHUR AND PHOSPHORUS. 355
described the mutual action of phosphorus and oxymuriatic combinations
gas or chlorine. I have noticed two compounds which appear f 1 Paohels
Par A} i : an i
to be distinct and peculiar bodies, formed by the union of the”
gas and the inflammable substance.. One is solid, white, and 1, Solid, white,
crystalline in its appearance ; easily volatile, and capable of pine a
: . . aE . bi when comb.
forming a fixed infusible substance by uniting with ammonia. with ammonia,
The other is fluid, limpid as, water, and, as I have since. found, ge ae
of specific gravity 1°45 ; it produces dense fumes by acting sp. ee. 146,
upon the water of the atmosphere, and when exposed to the es pe
atmosphere gradually disappears, leaving no residuum. ; 1: eaeslor ewes
The composition of the white sublimate is very easily.as- atmos. and
certained by synthetical experiments, such as I have described eee HON.
ae . . 5 . ee ee ‘ t,
on a former occasion in the Transactions. By employing egy Gra
chlorine dried by muriate of lime in great excess, and making ores 3 of
the experiments in exhausted vessels, and admitiing solation pega gee ra
of chlorine to ascertain the quantity of gas absorbed, I have
ascertained, that three grains of phosphorus unite with about
twenty grains of chlorine to form the sublimate.
If the phosphorus be in great excess in the experiment of "Phe second, or
its combustion in chlorine, some of the liquor is formed with the liquor, is
the sublimate ; but to obtain it in considerable quantities, phos- fully aera
phorus should be passed in vapour through heated powdered by passing Me
on, : p por of phosph.
corrosive sublimate. A bent glass tube may be used for the ehrobel Hor
process, and the liquor condensed in a cold vessel connected corros, subl.
with the tube.
I have not been able to determine its composition by syn- i contains 3
thetical experiments ; but by pouring it gradually into water, phosph. and
suffering the water to become cool after each addition of the re oe
liquor, and then precipitating the solution by solution of nitrate quantity con-
of silver, I have ascertained the quantity of chlorine and of ee a
phosphorus it contains. 13°6 grains, treated in this way, af-
forded 43 grains of hornsilver.
It is evident, from this analysis, compared with the result of
the synthetical experiments on the sublimate, that the quantity
of phosphorus being the same, the sublimate contains double as
much chlorine as the liquor.
When phosphorus is heated in the liquor, a portion is dis- 74, liquor
solved, and it then, when exposed to the atmosphere, leaves a on ate
film of phosphorus, which, when the liquor is thrown on‘paper, PoO*PHORN®:
mstally inflames: a substance of this kind was first procured
Aa2 | by
as
Wy
=>)
The sublim.
SULPHUR AND PHOSPHORUS.
by MM, Gay Lussac and Thenard, by distilling phosphorus
and calomel together 5 and it may be produced in the experi-
ment with corrosive sublimate, if sufficient heat be used ta
sublime the phosphorus, or if there be not an excess of the
corrosive sublimate. JT have made no experiments, in order to
ascertain the quantity of phosphorus the liquor will dissolve,
When the white sublimate is made to act upon water, it
combines with dissolves in it, producing much heat. ‘The solution evapo-
water, and
after evap, af- tated affords a thick liquid, which is a solution of pure phos-
fords sol. of
phosphoric ac,
The liquor, by
similar treat-
ment, affords
crystals.
Gas emitted
during its
combustion,
which is hy-
drophospho-
yous acid.
Properties of
the gas,
phoric acid, or a hydrate of phosphoric acid.
When the liquor is treated with water in the same way, it
furnishes likewise a thick fluid of the consistence of syrup,
which crystallizes slowly by cooling, and forms transparent
parallelopipedons.
This substance has very singular properties: when it is
heated pretty strongly in the air, it takes fire and. burns bril-
liantly, emitting, at the same time, globules of gas, that inflame
at the surface of the liquid. ‘This substance may be called
hydrophosphorous acid; for it consists of pure phosphorous
acid and water. This is proved by the action of ammoniacai
gas upon it ; when it is heated in contact with ammonia, water
is expelled, and phosphate of ammonia formed ; and it is like-
wise shewn by the results of its decomposition in close vessels,
which are phosphoric acid anda peculiar compound of phos-
phorus and hydrogen.
Ten parts in weight of the crystalline acid I found produced
about 8'5 parts of solid phosphoric acid, and the elastic pro-
duct must of course have formed the remainder of the weight,
allowing for a small quantity of the substance not decom-
posed.
The peculiar gas is not spontaneously inflammable ; ; bat
_explodes when mixed with air, and heated toa temperature ra-
ther below 212°,
Its specific gravity appeared from an experiment in which a
small quantity of it only was weighed, to be to that of air
neatly as 87 to100. Water absorbed about one-eighth of its
volume of this gas, Its smell was disagreeable, but not nearly
so fetid as that of common phosphuretted hydrogen.
When it was'detonated with oxygen, it was found that
three
SULPHUR AND PHOSPHORUS, 857
three of it in volume absorbed more than five in volume of
oxygen, anda little phosphorus was precipitated.
When potassium was heated in contact with it, its volume
increased rapidly till it became double, and then no further
effect. was produced. The potassium was partly converted
into a substance having all the characters of phosphuret of
potassium; and the residual gas absorbed the same quantity
of oxygen by detonation as pure hydrogen. When sulphur
was sublimed in the gas over mercury, the volume was like-
wise doubled ; a compound of phosphorus and sulphur was
formed, and the elastic fluid produced had all the characters
of sulphuretted hydrogen.
It appears from these, experiments, that the peculiar gas The gas con-
consists of 4°5 of hydrogen in weight to 22'5 phosphorus ; reuaghh oO
and its composition being known, it is easy to determine the phosphorus.
composition of the hydrophosphorous acid, and likewise the
quantity of oxygen required by a given quantity of phospho-
rous acid to be converted into phosphoric acid; for, for every
volume of gas disengaged, a volume of oxygen “must have
been fixed in the phosphoric acid.
And calculating for 174 grains, 30 parts of oxygen must
be fixed in the 150 parts of phosphoric acid, and 20 parts of
phosphorus disengaged in combination with 4 parts of hydro-
gen; and on the idea of representing the proportions in Taking hvdro-
which bodies combine by numbers, if hydrogen be considered a sis
as unity, and water as composed of two proportions of hydro- aie oy ef
gen, 2, and one of oxygen 15*, phosphorus will be repre- ie geen
sented by 20. a enh ih
When the compounds of chlorine and phosphorus are acted Compound of
on by a small quantity of water, miuriatic acid gas is disen- chlor. and
: : “5 : -, phos. acted on
gaged with violent ebullition, the water is decomposed, and it by water give
is evident that for every volume of hydrogen disengaged in mer. acid gas
combination with the chlorine, half a volume of oxygen mus; paehe Loe
be combined with the phosphorust ; and the products of the the phos.
mutual decomposition of water, and the phosphoric compounds
* Supposing 100 cubical inches of the gas to weigh 27 crains,———
27—4'5 the weight of 200 cubical inches of hydrogen == 22°5 prains.
+ This mode of estimation is the same as that I have adopted on a
former occasion, except that the number representing oxygen 18
- doubled to avoid a fractional part,
of
358 SULPHUR AND. FHOSPHORUS.
of chlorine are merely the phosphoric acid from the sublimate,
and the phosphorous acid from the liquor, and muriatic acid
gas; so that the quantity of phosphorus being the same, it is
evident that phosphoric acid must contain twice as much oxy-
gen as phosphorous acid, which harmonizes with the results
nel a facts of the decomposition of hydrophosphorous acid. For supposing
phosphoric water to be composed of two proportions of hydrogen, and
acid contains one of oxygen, aud the number representing it 17; then 174
AA Bice parts of hydrophosphorous acid must consist of two propor-
phosphorous tions; 34 parts of water, and four proportions of phosphorous
acid. acid, containing 80 of phosphorus and 60 of oxygene ; and
three proportions of phosphoric acid must be formed, con-
taining three proportions of phosphorus 60, and six propor-
tions of oxygen 90, making 150. we
Water andthe . It is scarcely possible to imagine more perfect. demonstrations
phosphor. _ of the laws of definite combination, than those furnished in the
compounds
shew com- mutual action of water and the phosphoric compounds. Na
Seige Saeee products are formed except the new combinations; neither
nite combina- Oxygen, hydrogen, chlorine, nor phosphorus is disengaged,
tion, and therefore the ratio in which any two of them combine
being known, the ratios in which the rest combine, in these
cases, may be determined by calculation,
Phosphoric I converted phosphorus into phosphoric acid, by burning it
acid produced jn a great excess of oxygen gas over mercury ina curved glass
by combust.
in oxyg, con- tube, and heated the product strongly. I found in several pro-
tains 20 phos. cesses of this kind, that for every grain of phosphorus con-
ape res: sumed, four cubical inches and a half of oxygen gas were
absorbed ; which gives phosphoric acid as composed of 20 of
phosphorus to 30°6 of oxygen; a result as near as can be
expected to the results of the experiments on the sublimate and
the hydrophosphorous acid. pe :
Unless the product of the combustion of phosphorus is
strongly heated in oxygen, the quantity of oxygen absorbed
is Jess, so that it is probable that phosphorous acid is formed, as
well as phosphoric acid.
Common Phosphorous acid is, usually described, in chemical authors,
phosphorous as a fluid body, and as formed by the slow combustion of phos-
Apa) AU phoros in the air; but the liquid so procured is, I find, a solu-
tion of a mixture of phosphorous and phosphoric acids. And
the vapour arising from phosphorus in the air at common tem-
peratures,
~
SULPHUR AND PHOSPHORUS.
peratures, is a combination of phosphorous acid and the aque-
ous vapour in the air, and is not, I find, perceived in air artifi-
cially dried.
In this case, the phosphorus becomes covered with a white
film, which appears to be pure phosphorous acid, and it soon
ceases to shine.
A solid acid volatile, at a moderate degree of heat, may be
produced by burning phosphorus in very rare air, and this
seems to be phosphorous acid free from water , but some phos-
phoric acid, and some yellow oxide of phosphorus, are always
formed at the same time.
359
The peculiar gas differs exceedingly from phosphoretted hy- Nature of the
drogen tormed by the action of earths and alkalies and phoss Peculiar gas,
phorus upon water ; for this last gas is spontaneously inflam-
mable, and its specific gravity is seldom more than half as
great, and it does not afford more than 1°5 its volume of
_ hydrogen when decomposed by potassium; it differs in its
qualities in different cases, and probably consists of different
mixtures of hydrogen with a peculiar gas, consisting of 2
parts of hydrogen and 20 of phosphorus; or it must contain
several proportions of hydrogen to one of phosphorus,
I venture to propose the name fydrophosphoric gas for the dendeneees
new gas; and according to the principles of nomenclature, I oF eh aa
have proposed in the last Bakerian lecture, the liquor con-
taining 20 of phosphorus to 67 of chlorine may be called phos-
phorane, and the sublimate phosphorana.
3. Of some Combinations of Sulphur.
I have shewn, in a paper published in the Philosophical chee
Transactions for 1810, that sulphuretted hydrogen is formed ®
ne sulphu-
by the solution of sulphur in hydrogen, and I have supposed reous acid.
that’ sulphureous acid, in like manner, is constituted by a
solution of sulphur in oxygen. ‘There is always a little con-
densation of volume in experiments on the combustion of sul-
phur in oxygen; but this may fairly be attributed to some
hydrogen loosely combined in the sulphur; and to the pro-
duction of a little sulphuric acid by the mutual action of hydro-
gen, oxygen, and sulphur.
It is only necessary, if these data be allowed, to know the
difference between the specific gravity of sulphureous acid gas
and
Weights of
the gases,
distinctly set
forth,
and their
numerical
composition.
Other experi-
ments consi-
dered.
SULPHUR AND PHOSPHORUS.
and oxygen, and sulphuretted hydrogen and hydrogen, to
determine their composition,
In the Philosophica) Transactions for 1810, page 254, I have
somewhat under-rated. the weights of sulphuretted hydrogen
and«sulphureous acid gases; for I have since found, that the
cubical inch measures, employed for ascertaining the volumes
of gas weighed, were not correct. From experiments which I°
think may be depended upon, as the weights of the gases
were merely compared with those of equal volumes of common
air, I found that 100 cubical inches of sulphureous acid gas
weighed 68 grains at mean temperature and pressure, and 100
cubical inches of sulphuretted hydrogen 36°5 grains, and the
last result agrees very nearly with one given by MM. Gay
Lussac and THENARD, a8 one at sige ve brother Mr,
Joun Davy. ” ee &
If 34, the weight of 100. cubed sical af Gxjeen gas, be
subtracted from 68, it will appear that sulphureous acid con-
sists of equal weights of sulphur and oxygen, an estimation
which agrees very nearly with one given by M. Berzetius 3
and if 22°7, the weight of 100 cubical inches of hydrogen be
subtracted from 365, the remainder 34'23 will be the quan-
tity of sulphur in the gas; and the number representing sul-
phur may be stated as 30; and sulphureous acid as composed
of one proportion of sulphur 30, and two of oxygen 30; and
phur, and two of hydrogen,
From the experiments of MM. Gay Lussac, it appears that
suiphuric acid decomposed by heat affords one volume of oxy-
gene to two of sulphureous acid: from this it would appear to ©
be composed of one proportion of sulphur to three of oxygen. |
J have endeavoured, in several trials by common heat and by
electricity, to combine sulphureous acid gas with oxygen, so
as to form a sulphuric acid free from water, but without suc-
“sulphuretted hydrogen as composed of one proportion of sul-
cess ; and it is probable, that three portions of oxygen cannot —
be combined with one proportion of sulphur, except by the
jntermedium of water. Mr. Darrow has supposed, that there.
isa solid sulpburic acid formed by the action of sulphureous —
acid gas upon nitrous acid gas. But I find, that when dried
sulphureous acid gas and nitrous acid gas are mixed together, |
there is no action; but by introducing the vapour of water, —
bi they
ee = S| ee eS ml ee ee ee eee ee
~~
Z il h
ag
os. |
|
SULPHUR-AND PHOSPHORUS. S61
they form together a solid crystalline hydrate ; which when
thrown into water gives off nitrous, and forms a solution of
sulphuric acid.
I have referred, in the Philosophical Transactions, to the Chlorine and
combination of chlorine and sulphur. I have been able to form sulphur.
no compound of these bodies, which does not deposit sulphur
by the action of water. When sulphur is satured with chlo-
rine, as in Dr. Taomson’s sulphuretted liquor, it appears to
contain, from my experiments, only 67 of chlorine to 30 of
sulphur.
4. Some general Observations.
Tt is a fact worthy of notice, that phosphoric and sulphuric Observations.
acids should contain the same quantity of oxygen to the same eee
quantity of inflammable matter; and yet that the oxygen phoric and _
should be combined in them, with such different degrees of sagriee kay
affinity. Phosphorous acid has a great tendency to unite with though the
oxygen, and absorbs it even from water: and sulphureous scaly lta
acid can only retain it when water is present. : ;
The relation of water to the composition of many bodies has Most precipi-
already occupied the attention of some distinguished chemists, Oe ee
and is well worthy of being further studied ; most of the sub- that ingre-
stances obtained by precipitation from aqueous solutions are, I erat.
find, compounds of water.
Thus zircona, magnesia, silica, when precipitated and dried
at 212° still contain definite proportions of water. And many
of the substances which have been considered as metallic
oxides, that I have examined, obtained from solutions, agree
in this respect 5 and their colours and other properties are mate-
rially influenced by this combined water. :
I shall give an instance. The substance which has been called Instance.
the white oxide of manganese is a compound of water and the
protoxide of manganese, and when heated strongly, it gives
off its water and becomes a dark olive oxide.
It has been often suspected, that the contraction of volume Contraction
produced in the pure earths by heat, is owing to the expulsion 2 ate re
of water combined with them. The following fact seems to arises from the
confirm this suspicion, and offers a curious phenomenon.. stoma of
Zircona, precipitated from its solution in muriatic acid by an
alkali,
362
Geological
Society.
_ followed with profit.
SCIENTIFIC NEWS.
alkali, and dried at a temperature below 300°, appears as a white
powder, so soft as not to scratch glass. When heated to 700°
or 800’, water is suddenly expelled from it, and, notwithstand-
ing the quantity of vapour formed, it becomes at the moment
red hot. After the process, it is found harsh to the feel, has
gained a tint of gray, its parts cohere together, and is become
so hard as to scratch quartz.
SCIENTIFIC NEWS.
Geological Society.
T the meeting of this Society, Dec. 4th (the president in
the chair) the reading of a paper by William Phillips,
Esq. M. G. S. ** on the views of Cornwall,” was begun.
The regular or metalliferous views of Cornwall are found,
with few exceptions, to run east and west. The known length
of many of these views is considerable, amounting, in some
instances, to two er more miles ; but their actual termination
at either extremity has in no case been satisfactorily ascertained ;
all that is known being, that they gradually become so poor
and narrow, as to make it no longer worth the miner’s while
to pursue them,
The dip or descent of the veins varies more or less from
perpendicular, inclining towards the north or south, which, in-
clination is called the underlie of the lode.
The depth of the veins is still less known than their longitu-
dinal extent, not an instance having occurred of a vein being
fairly worked out: many veins have indeed been relinquished,
but only on account of the expences of working them exceed-
ing the produce. The deepest mine now in work in Cornwall,
is Dolcoath, some of the workings of which are 228 fathoms
below the surface.
The usual width of the veins that are worked, varies from
one foot to three ; in particular instances, however, portions of
veins occur twenty-four feet, and even thirty feet wide; and,
on the other hand, a vein of tin, not three inches wide, has been
2
The
SCIENTIFIC NEWS. 363
The substances that accompany the metallic ores’ (or the Geological
vein-stones) vary considerably, not only in different mines, but Society.
in different parts of the same vein ; and it is from these, and
not from their metallic contents, that the miner’s nomenclature
of the veins is derived.
Gossan is a friable substance of a loose texture, consisting
of clay, mixed more or less with silicious matter, and coated
or tinged with oxide of iron, Its colour varies. from light yel-
Jow to deep and brownish black. A gossany lode is moré
common than any other, and is considered as promising both for
copper and tin.
When quartz predominates, the vein is called sparry ; and if
the quartz is considerably compact, it is looked upon as a very
‘unfavourable indication, more especially if the vein becomes
narrower as it descends.
If iron pyrites abounds, the vein is said to be mundicky,
When this substance occurs at a shallow level, it is considered
as not unpromising, more especially if mingled with copper ore
as it descends,
A vein containing a large proportion of chlorine, is termed
. a peachy lode, and promises for tin rather than copper.
_ A-vein is said to be flookany when one or both of its sides
is lined with bluish white clay. It sometimes is so abundant,
as to occasion considerable difficulty and expence to prevent it
from slipping down, and obstructing the works.
When the contents of a vein consist of a hard compact
substance, of a greenish or brownish colour, which appears
to be chiefly a mixture of quartz and chlorite, the vein is dee
nominated caply. Tin is often found in it, copper rarely.
When the ore, whether of tin or copper, is found in de-
tached stones or humps, mixed loosely with the other contents
of the vein, it is termed a pryany lode.
A vein abounding in blende, is called a Black Jack lode, and
is considered as unpromising for tin, but a good sign for copper.
When a vein contains granite in masses or blocks, or in a
state of semi-decomposition, it is termed a growan lode; and
is generally considered as more promising for tin than for cope
per. Of late, however, many rich veins of copper have been
found in the granitic districts of Cornwall.
The experienced miner by no means implicitly relies on even
. the
364
Geological
Society.
SCIENTIFIC NEWS.
the most promising symptoms, for all of them at times are
found to mislead. The following, however, are those, in favour
of which he is more especially prepossessed. All gosany lodes
in general ; the early discovery of pyrites with portions of yel-
low copper ore, also of blende and of gelina; and the cutting
a good course of water, especially if it be warm.
The discovery of veins is effected in various ways.
The ancient method of shoding or tracing up waterecourses,
when pieces of ore are found to occur among the rolled stones
in their channels, is now rarely resorted to. The common
method is to work drifts across the country from north to
south, by which all veins in the district thus examined, are
sure to be cut through. Veins are often found in driving
adits and levels for the working of known lodes ; and not un-
frequently are stumbled upon by mere accident in digging
ditches and foundations for walls. —
-December 18.
The president in the chair.
The continuation of Mr. Phillips’s paper on the Veins of
Cornwall, was read.
The contents of a vein may be divided into those which are
valuable, and those which are not so : the latter forming gene-
rally by far the largest portion, are technically called deads, and
are left in the vein both to avoid the unnecessary expence of
raising them to the surface, and for the very important purpose
of preventing the two walls of the vein from coljaping, and
thus destroying the works: in addition to the deads, strong
pieces of timber are frequently made use of, Sometimes large
wedged- shaped fragments of rock, called by the miner horses,
occur in the vein, partially cutting off the regular contents of
lode, though seldom, if ever, entirely obstructing it. Veins
of copper ore are, however, particularly liable to capricious and
fotal obstructions, without any obvious cause, In propor-
tion as the rock becomes harder, the vein always becomes more
narrow. |
One of the first objects in opening a new mine, is to drive an
adit or horizontal gulley from the lowest convenient level, for
the purpose of carrying off all the top water. One adit often
seryestwoor three mines; and there is one, called the deep
adit,
SCIENTIFIC NEWS. 365
adit, which opens on one of the creeks of Falmouth harbour, Geological so-
the entire subterranean length of which is about twenty-four ee
miles,
Copper veins, which, fifty years ago, were considered by the
Cornish miners to be peculiar to Schist, have, of late, been found
in the parishes of Givenass and Redruth ‘to pass freely from
Schist into Granite, and back again to Schist without any de-
terioration. The texture and hardness of both rocks is liable
to considerable variation, affecting, of course, the profit and
progress of the miner often in a very remarkable degree. Two
shafts of Fluel Alfred were sunk in Schist, and the cost of one
did not exceed 51]. per fathom, while that of the other amounted
to 551. for the same length.
The metalliferous, or east and west veins, are crossed by
others, the direction of which is nearly north and south. 7
These latter are called gross courses, and rarely produce
‘copper or tin, or any other metallic substance. The principal
‘practical advantage derived from~ these’ veins, especially when
consisting of clay, is, that they oppose an effectual obstacle to
the passage of water, and therefore the miners do not willingly
pierce them without some adequate object in view. The dis-
advantage of them is, that they not only interrupt the course of
the metalliferous veins, having them from a few inches to several
fathoms; but not unfrequently totally impoverish them, so that
along and costly search after the heaved part of a vein, often
terminates in the mortifying discovery, that it is not worth |
‘pursuing, as was most strikingly exemplified inthe correspond-
ing veins of Huel Jewel and Tol Carn.
There is another species of vein called a Contre or Gaurter,
the direction of which is, for the most hk NE. and SW.
These are mostly, if not always, metalliferous, and often re-
markably rich, of which the mines of Huel Alfred and Her-
jand have afforded most splendid instances.
\
—agee
-Phosphorescence of Bodies.
Deseignes continues his experiments on the phosphorescence
of bodies, It was formerly published, that he found, that by
violently compressing water in a glass tube, by a blow, it be-
came
366
SCIENTIFIC NEWS,
came luniinous. He has made the same experiment with a
great number of liquids, which became luminous by the same
treatment ; such as olive oil, volatile oils, alcohol, sulphuric
ether, acetous, anda saturated and boiled solution of potash,
&c.
He ascertained, at the same time, that the temperature of
all these liquids was at the same time raised.
Solid bodies likewise become luminous. by compression.
He filled the same tube with powdered chalk, and gave. it a.
blow in the dark. The whole mass was then penetrated with
a strong light, which disappeared like a flash of lightning.
He had the same results from flowers of sulphur, dried sul-
phate of magnesia, nitrate of potash, black oxide of manga-
nese, ashes, powder of mica, and of vegetable coal, &c. and,
in a word, every thing that was at hand.
The same bodies, struck with an hammer or an anvil, like-—
wise gave atmospheric jight; but particularly fluat of lime,.
phosphate of lime, and caustic lime; but sulphur, the metallic
oxides by calcination, and burned alum, gave a very feeble
light.
his difference seemed to him to have arisen from water in
the solid state contained in these bodies. He ascertained this
by the following experiments. He poured a few drops of wa-
ter upon caustic lime, and it became very luminous by the
blow. And the same effect was produced on other bodies. __.
Other experiments showed, that this light produced by com-
pression is not electrical, but arises from the sudden approach
of the particles of the bedies to each other.
¢
Questions from a Correspondent on Subjects tending to encourage
the Iron manufucture of this Country.
Has the making of iron had a gradual increase since 1800?
and since that year, have considerable works been erected or
established in addition throughout the United Kingdom, and -
principally where ?
What
SCIENTIFIC NEWS.
What quantity of iron may be now made in England,
Wales, Scotland, Ireland—this is, iron into ars ?
What may be the quantity in same manner of cast iron into
various purposes for domestic and general use ?
No doubt the British ore, if worked .by wood, could produce
equal iron to any we import ; but is the quality of iron im-
proved by working with coa! at the present period, and is it
possible by coal to make it equal to the foreign we import ?
Is any quantity of British cast ware exported, as well as Bri-
tish iron in bars, and where to principally ?
Is it not possible to manufacture all the iron we require for
home consumption and exportation amongst ourselves ? and
by what means could it be adopted ?
Dees not the duty on the importation of foreign iron act as
a bounty upon our own ? or does the importation of foreign
iron interfere with that of our own manufacture ? and what
means would be the most effectual to depress the importa-
tion of foreign, by a competition in the manufacture of our
own ?
Is it possible to increase the making of iron in the United
Kingdom adequate to all wants and exportation without
the danger of exhausting our own native resources, if the
iron trade could be made the principal staple af the coun-
try?
In what part of the United Kingdom can the Iron be made
the cheapest ?
What may be the whole aggregate quantity of Iron, cast in
bars in various iron utensils; and the whole manufacture
of iron ware, from mative ore, throughout the United King-
dom? ©
If the greatest quantity of iron is made in Wales, what
may be the expence of conyeying it up to London?
Mete-
36
$68
SCIENTIFIC NEWS.
Meteorological Table for 1812. Extracted from the Register kept
at Kinfauns Castle, the residence of Lord Gray, three miles
almost due East from Perth, N. Britain, about ninety feet
_ above the level of the ray.—Lat. 50° 24’.
1812,
January.
February.
March.
April.
May.
June.
July.
August.
September,
October.
November.
December.
Average of ||
the year
ox ee
Communicated by his Lordship.
Morning, 8 o'clock.| Evening, 10 0’clock,
Mean height of.
| Barom.| Ther.
29°92 | 30°60
29°64 | 37°55
29°96 | 33°46
30:09 | 38°40
; 30:02 | 48°20
30°01 | 54°17
30:04 | 55°22
3009 | 55°10
30°03 | 52°00
29'47 | 45:00
29 89 | 37°76
30°09 | 34°00
29'937 |. 43°43
Meun height of
Barom.| Ther.
30 02 | 45°45
30°02 | 52°00
30°05. | 52°97
30°19 | 53°16
30°03 | 49°00
29°50 | 45°10
29°91 | 38°10
30:14 | 35°00
29°953| 42°40
Depth |No. at days.
of Rain |S pe)
in: 100l © Hi S
72 | -7 | 24
WUG bbAgs by kB
22°75 | 149 | 217
a A NS a
In the course of the present month, will be published, in
one volume octavo, a Treatise on the Motion of Rockets, to- -
‘gether with the Theory and Practice of Naval Gunnery ; by -
W. Moore, of the Royal Military Academy, Woolwich,
ne INDEX. te
A.
Accum, Mr. his crystallographic
models, 237
Antimony and chlorine, 121
Allan, Mr. J., his reflecting circle, 112
Allen, Mr., his electric column of 1000
pieces, 82
Apples, 255
Apricots, 255
Arsenic and chlorine, 121
Arsenic, as a poison, 2614
B.
Banks, Sir Joseph, 159
——— his orticultural observations,
251
Beat, musical, very curious instance
of, 163
Bennet, H.G, Esq. on the geology of
Madeira, 37
Berzelius, M. 319
SUPPLEMENT—VoL, XXXIITI. No, 155.
Blood, 23
——, 179, its colouring principle, 183
Brodie on poisons, 258
Bostock, Dr, 29
————,, on alkali in animal fluids,147
» 285
Brande, William Thomas, Esq. on
the blood and other animal fluids, 23
——-—, on the blood, 179
Brown, Dr. 147
Buds of plants, 1
C.
Carbonate of lime, its primitive crys-
tals, 208
Circle, reflecting, by J. Allan, 112
Cherry, perfumed, 158
Chladni, 263, 264
Chlorine, its combinations, 10. 120
——-——, and oil of turpentine, 194
Bb Chyle,
370 INDEX.
Chyle, 24
Coagulum of blood, 25
Clocks, their rate affected by attrac-
tion of the weight on the pendulum,
92
Colouring matter of blood, 31
Column, electric, 81
Combination, chemical, important
statement of its doctrine, 127, 134
Cornwall, W. Phillips, Esq. on its
mineral views, 362
Copper, combined with chlorine, 11
Corai Fishery, Dr. Ferrara on, 136
Crotch, Dr. 164
Crystallographic models, by Accum,237
ee, Iceland, 346
D.
D’Arcet on Prussian blue, 268
Davy, Sir H, on combinations of sul-
phur and phosphorus, 354
Davy, John, Esq. on the combinations
of chlorine, 10, 120.196
Definite proportions in chemistry,
doctrine of, 127. 134
Delambre, 326
Deliquescence of bodies, by M. Gay
Lussac, 282
De Luc, J. A. Esq. on an electric co-
lumn, 81
————--—=—— on electricity by
friction, 196
———— on hygrology, 291
Desmortiers, his pneumatic tinder-
box, 220 ;
Dissections of plants in general, 9
Dogwood, Jamaica, 146 ’
E.
Electricity by friction, Mr. De Lue
on, 196
Electric column of De Luc, 81
Explosive Compound, new, 32¢
Eyes, 102
Falling Stats, 33.
Farey, Mr J . on falling stars, 3$
Ferrara, Doctor Alfio, on the Sicilian
coral fishery, 136
Figuier on hydrosulphate, 74
Fishery, coral, near Sicily, 136
Flowers, their nectaries, 174
Fluids, animal, 179
Forster, Mr. B. M. 88
G.
Gases, sonoriferous vibrations of, 16%
Gay Lussac, M. on deliquescence, 28%
—On decomposition of sulphates by
a t,44
Geology of Madeira, by H. G. Bennet,
Esq. 37
Geological Society, 362
Goering, on red-beet, 75
Grasses, 6, 7
Gray, lord, his Mineralogical Register
at Kiafauns Castle, 36% -
A.
Hamilton, W. Esq. on the Jamaica
Dogwood, 145
Hardy, Mr. ixis compensation, 219
Hassenfratz on the apparent figure of
stars, 95
Hauseman, M, 91
Hautbois, 256
Hemp, of Dorsetshire, 151
Heracleum spondylium, 5
Horticultural observations, 251
Howard, L. Esq. see Meteorological
Journal
Huygkens, 391
Hygrology and Hygrometry, with re-
lation to the atmosphere; by J. A.
De Luc, Esq. 291
J,
5 acquin, 264
Jamaica Dogwood, 145
Jamrosade, cultivation of, by M.
Thouin, 315
I.
Ibbetson, ‘Mrs. Agnes, on the interior
buds of plants, i—On the nectaries
of flowers, 171—On the growth or
increase of trees, 241—On the roots
of trees; 334
Insect, seized by the nectary of the
Tris, 175
Tron, combined with chlorine, 20—
Questions concerning its Predyesiony
trade, &¢, 366
K.
Kerby and Merrick, Messrs. on the
sonoriferous vibrations of the gases,
161
Keys of musical instruments, new ara
rangement of, 215
Klaproth, his analyses, 228
Knight, T. A. Esq. on the emission of
roots from layers, 313
L,
Lamp, ceconomical, 211
La Place on double refraction, 104
Larrey, M. on the Vicuna, 66
Lead and Chlorine, 121
Lelicur, M. on the diseases of fruit
trees, 159
Leslie, 162
Libavius, liquor of, 17
Light, polarity of, 344
Lymph, 28
M. r
Madeira, geology of, by H. G. Benuet,
Esq. 37
i ae eae Malus,
372 INDEX.
Malus, popular statement of his experi-
ments on light, 344
Marcet, Dr. on alkali in animal fluids,
147. 285
Maycock, Dr. 81. 196
Measurement, 521
Meteorological Journal, 22. 118—At
Kinfauns Castle, by Lord Gray,
3568
Mineralogical observations at sea, by
Peron, 54: 62
Monochord, 163
N.
Nectaries of Flowers, 171
Newion, Sir J, 321
O.
Oat grass, 79
Oil of tarpentine and chlorine, 194
Pu.
Pears, 255
Pearson, Dr. on alkali in animal fluids,
285
Pendulum, affected by attraction of
the weight, 99—New Compensation,
217
Phillips, W. Esq. on the mineral veins
of Cornwall, 562
Phosphorus, Sir H. Davy onsome com-
binations of, 354.
Phosphorescence of bodies, 365
Piscidia, Erythryna, 145.
Pitch of middle Cia music, 163
Plants, on their jnterior buds, by Mrs.
Ibbetson, 1—bulbous, 8
Plums, 255
Poisons, M. Brodie on, 258
Sylvester on, 306
Polarety of light, 344
Polypi of the coral, 141
Porret, jun, Mr. on combination of
chlorine and oil of turpentine, 194
Proportions definite in chemical com-
binations, 127. 134
Prunus, maheb, or perfumed cherry,
158
Prussian blue, 268
Pump, remarkable effect of hot liquid
init, 189
R.
R. B. 189
—— his new compensation pendulum,
217
Red beet, 75
Refraction, double, Laplace on, 104
Reid, M. Tho. on the attraction of the
weight of a clock upon the pendu-
lum, 92 .
Rodriguez, 324
Roots, T. A. Kuight on their emission
from layers, 315
Roxburgh, Dr. Wm, on the teak tree,
548
Sex cate, or kale, 157
Scurvy, 55
Serres, Mich. de, on Turkish rose
pearls, 7&
Serum
INDEX. 373
Serum, 27. 29
Singer, Mr. G. J. on falling stars, 33
Soda, hydrosulphate, 74
Soniferous vibrations of gases, 161
Stars, their apparent figure, 95
Stanhope, Lord, his monochord, 163
Starch, sugar of, 274
Strawberries, 256
Sugar of starch, 274
Sulphates, decomposition of, by heat,
44
Sulphur, Sir H. Davy on some combi-
nations of, 354
Sylvester, Mr. Charles, on metallic
poisons, 306
Tk
Teak tree, Dr. Roxburgh on the, 348
Thouin on the cnltivation of Jamro-
sade, 315
Tilloch, Mr. 88
Tinder box, pneumatic, by Desmor-
tiers, 220
Tin, combined with chlorine, 16
Tollard on oat grass,.79
Trees, Mrs. Ibbetson on their growth
or increase, 241
———, roots of, Mrs. Agnes Ibbetson
on, 334
Trotter. John, Esq. his new arrange-
ment of the keys of musical instru-
ments, 215
Tuthill, Dr. on the sugar from potatoe
starch, 319
Turkish rose pearls, 78
V.
Vicunas, from Peru, 66
Vogel, M. on sugar of starch, 274
Ww.
W.N. 189
Way, H. B. Esq. on hemp, 151
Wheat, 7
Wollaston, Dr. onthe primitive crystais
of carbonate of lime, bitter spar, and
iron spar, 208
Woorara, poison of, 259
Y.
Young, Dr. 163
Z.
Zinc and chlorine, 124
END OF THE THIRTY-THIRD VOLUME.
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