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ANNALS OF PHILOSOPHY ;
OR, MAGAZINE OF
CHEMISTRY, MINERALOGY, MECHANICS,
NATURAL HISTORY,
AGRICULTURE, AND THE ARTS.
BY THOMAS THOMSON, M.D. F.R.S. L. & E. F.L.S.
REGIUS PROFESSOR OF CHEMISTRY IN THE UNIVERSITY OF GLASGOW,
MEMBER OF THE GEOLOGICAL SOCIETY, OF THE WERNERIAN SOCIETY, AND OF THE
IMPERIAL MEDICO-CHIRURGICAL ACADEMY OF PETERSBURGH ;
ARTHUR AIKIN, F.L.S, MEMBER OF THE GEOLOGICAL SOCIETY, SECRETARY TO
THE SOCIETY FOR THE ENCOURAGEMENT OF ARTS, MANUFACTURES,
AND COMMERCE; AND
JOHN BOSTOCK, M.D. F.R.S, weMBER OF THE GEOLOGICAL sociETY, &c. &c.
VOL. XII.
JULY TO DECEMBER, 1818.
onda :
Printed by C. Baldwin, New Bridge-street;
FOR BALDWIN, CRADOCK, AND JOY,
47, PATERNOSTER-ROW.
—~<9———
1818.
TABLE OF CONTENTS.
NUMBER LXVII.—JULY, 1818.
Page
History of Physical Science from the Commencement of the Year 1817.
PartI. By Thomas Thomson, M.D. F.R.S. &c. &c. . pete et Ad
Biopraphical Sketch Of Brissqm. oe oe ooo es ace os wo clos an ane tin nweeees 3 43
On the Geography of Plants. By N. I. Winch, te Ecteho ecteAseaeg 45
Account OL 2 SLOT SUSSEX I W720... «oes els cha) puivapsis nic eleaibieis ae ois oe 49
On the Construction of Fire-places to Steam Boilers. By John and Phi-
lip Taylor, Civil Engineers ........sesseeceeeccceee ceeceeecrenenes bi
Observations on the River Zaire ...... Sue Re IaG6e AcBaeewiae arabes nee aor
Morphium and Meconic Acid........cesseeee cece sees teeeceeceeeeeeee 55
On softening Steel by heating and quenching it, and on the hardening and
tempering it at one Operation. By 'Thomas Gill, Esq.........-...++. 58
History of Dr. Brewster’s Kaleidoscope, with Remarks on its supposed
Resemblance to other Combinations of plain Mirrors. From a Corre-
BEVELED bays ines a asaiein cic ee cieielaeae esas ee seals iptalsiaie e's eisiaaisiagini= s\sle:n ine aisle 59
Proceedings of the Royal Society, May 28, June4, and 11............ 67
—_—_—_—_—_——. Geological Society, March 6, April 3, 17, May 1,
and 15 es Evens sun ee tale ies alorcis sini tein siace ate 69
Linnzan Society, May 5, 25, June 2, and16...... 71
Attempts to penetrate into the Interior of Africa . 1.2... 0222s eeueeeenee 72
PRETEEN GP wcatetle Ue estas tte senor Clas (ara\eiete diary « piatsle oip.cteiista ies (ssiasiaia 73
Cheveredtirittor:s, distilling Apparatus’... zy. sts. 1aiisisie moet meyepe's a\e' 4°80
Vegeto-animal matter. .........6- SOO aka. 3°60
Incrystallizable sugar . .....--..+4- OO Bes taoaie . 0°05
Gummy matter approaching starch .. OF baer eit. 0-10
LR GiB RS ARR NPE fa Se Re BO sive: OLS ec Fis cnt eee
Phosphate. of Hume «2. 455, «ce «ne ease « «yy O40" io niet etal
Muriate of potash 7
Phosphate of potash
oe acid f ; > a eau taCRs Trace.
egetable salt with base of lime |
Ditto with base of potash |
Sulphur
100-00 100-00
(Ann. de Chim et de Phys. iv. 370.)
1818.] the Commencement of the Year 1817. Part I. 39
10. Juice of Carrots—Laugier has observed that when the
juice of carrots is subjected to fermentation, manna, in the state
of crystals, makes its appearance in it.—(Jour de Phys. Ixxxv.
472.) ,
11. Potatoes.—Vauquelin has subjected a great many different
varieties of potatoe to analysis. The juice procured from the
root by expression was the particular object of his research ; and
‘im this he Ras detected the following substances :
1.. Albumen of a black colour.
2. Citrate of lime.
. Asparagin.
. A bitter aromatic resin.
. Phosphate of potash and phosphate of lime.
. Citrate of potash and citric acid.
. A peculiar animal matter.
(Jour. de Phys. Ixxxv. 113; and Annals of Philosophy, ix. 430.)
12. Almonds.—The emulsive seeds have been thought to con-
sist principally of a mixture of starch and fixed oil. M. Vogel,
however, has lately discovered that the bitter almond contains no
starch but albumen, or a substance analogous to curd, in the
proportion of 30 per cent. This interesting discovery has been
confirmed by the result of an examination of the sweet almond
by M. Boullay ; and it is not improbable that the other emulsive
‘seeds are similarly circumstanced.—(Schweigger’s Jour. xx. 59;
Journ. Pharm. Aug. 1817; Annals of Philosophy, 1x. 426.)
13. Copper as a Constituent of the Ashes of Plants.—Bucholz
and Proust announced a good many years ago that they had
detected copper in the ashes of certain plants. Very lately
Dr. W. Meissner, an apothecary in Halle, made a set of experi-
ments on the same subject. He detected traces of copper in
the ashes of the following seeds :
SID OF > OO
Grana Paradisi,
Cardomomum minus ;
and the roots of
Curcuma longa,
Galanga ;
but the quantity is so small that it is by’ no means easy to dis-
cover its existence at all. He found the action of the galvanic
battery to be the most unequivocal means of detecting the
presence of that metal when it exists in very small quantity in a
mixed mass.—(Schweigger’s Journal, xvii. 340.)
XII. ANIMAL SUBSTANCES.
1. Nourishing Properties of Substances destitute of Azote.—
Most of my readers are probably acquainted with the very
curious experiments made some time ago by M. Magendie, in
Paris. He fed dogs on sugar, allowing them no other nourish-
40 History of physical Science from (Jury,
ment except water. The animals swallowed the food with
avidity; but they gradually became thin, and in about six weeks
died of starvation. An ulcer always broke out in the cornea of
the eyes, and they lost their sight some days before their death.
The same experiments were repeated on other dogs, substituting
gum and butter for sugar. The result in both cases was exactly
the same. From these experiments, M. Magendie drew as a
conclusion that food destitute of azote is incapable of nourishing
dogs.—(Ann. de Chim. et de Phys. 111. 66.)
hese experiments are of so decisive a nature that they seem
at first sight perfectly conclusive. There is one circumstance,
however, which would render it desirable that the experiments
should be repeated in a somewhat different manner—l allude to
the great fudluende of habit upon the digestive powers of animals.
It is possible that the stomach of dogs may not be capable at
once of digesting food so different from what these animals are
accustomed to, as sugar, gum, and butter. But ifthe change of
food were brought about gradually, and not all at once, is it not
probable that dogs might be made to live upon sugar, gum, and
even butter? A sheep is accustomed to live upon vegetable food,
and it is incapable at first of digesting animal food ; but it may
be brought by degrees to relish animal food, and even to live on
it. Itis said that in such cases the animal becomes incapable
of digesting vegetable food. This effect of habit renders it very
‘difficult to draw unexceptionable consequences from experiments
on living animals. ;
2. Composition of Animal Substances—Berard has subjected
several animal substances to analysis by heating them in a glass
tube previously mixed with peroxide of copper. The following
table exhibits their constituents as then obtained :
, Constituents by Weight, Total.
Azote. Carbon. Oxygen. | Hydrogen.
Dress s'fe 43°40 19-40 26°40 10-80 100
Uric acid. ..| 39°16 33°61 18°89 8:34 100
Butter. ....| 00°00 | 66:34 14-02 19-64 100
Bai iis Sass 00°00 | 69-00 9°66 21°34 100
Mutton suet.) 00°00.| 62-00 14-00 24:00 100
Cholesterine.| 00°00 72°01 6°66 21°33 100
Cetine. ....| 00°00 81-00 6:00 13-00 100
Fish oil ....| 00-00 79°65 6:00 14:35 100
Urate of barytes he found composed of
Uric acid. ..... 61:64 2.2.04. 100°00....... 15°667
Barytes ...... 38°36 ....4. 62:23 ....2. O75
100-00 ‘
1818.] the Commencement of the Year 1817: Part I. 4)
Urate of potash is composed of
Uric acid. .... 70°11 ...... 100-00 ...... 14074
Potash. ...... 29.89 Remain APO wee tien,’ 0 OO
100-00"
(Ann. de Chim. et de Phys. v. 290.)
Dr. Prout has subjected urea, sugar, and uric acid, to analy-
sis in the same manner as Berard. From the great degree of
recision with which he makes all his experiments, and their very
equent repetition, in the present case I am disposed to place
very great confidence in their accuracy. A full detail of these
experiments has been inserted in the Annals of Philosophy,
ix. 352.
Berard has made a very curious experiment. He mixed toge-
ther
1 volume carbonic acid,
10 volumes carbureted hydrogen,
20 volumes hydrogen, ‘
which nearly represent the elements of fat, and passed the mix-
ture through a red-hot porcelain tube. He obtained a substance
in small white crystals, lighter than water, soluble in alcohol,
and fusible by heat into a substance similar to fixed oil. Dobe-
reimer, also, by mixing coal gas and aqueous vapour in a red-hot
iron tube is said to have produced a substance similar to fat.
3. Cetine—This is the name which Chevruel has given to the
substance known in commerce by the name of spermaceti. He
has published a new memoir on the subject, in which he has
altered some of his former opinions ; but as I have hitherto seen
only.a part of this memoir, [ think it better to defer this subject
till our next historical sketch.
4. Conversion of Animal Bodies into Fat.—M. Gay-Lussac
has announced it as his opinion that the apparent conversion of
animal bodies into fat is merely a deception ; and is nothing else
than the wasting away of the muscular fibres while the fat
remains. He states some experiments which corroborate this
opinion. Fibrin of blood was kept in water renewed once every
two or three days for three months. It was all wasted away,
and no fat whatever remained. Muscle of beef and liver being
treated in the same way, some fatty matter remained (Ann. de
Chim. et de Phys. iv. 71). I have little doubt, notwithstanding
these experiments, that in certain cases, at least, something more
happens than mere putrefaction. A remarkable example occur-
red to me last winter. About the year 1684, a poor woman was
drowned in a moss in Ayrshire, as she was going to visit her
friends. She was carried to the neighbouring church-yard to be
42 History of physical Science from {[Jury,
interred ; but the curate (for the church of Scotland at that time
was episcopalian) refused to permit her body to be deposited in
consecrated ground. She was in contequence carried back, and
buried in the place where she was found. The proprietor of the
estate had the curiosity last year to open the grave. The body
was found quite entire, and even the plaid in which it had been
wrapped was in good preservation; but the whole body was
converted into a hard saponaceous matter. I had the curiosity
to examine a portion cut from the thigh, which was sent to the
Glasgow museum. It was hard and firm, and had the aspect of
soap. On treating it with alcohol, I found that it was composed
chiefly of the adipocire, which has been so often described and
exammed that it would be superfluous to give any description.
But the whole was not adipocire ; there remained undissolved
by the alcohol a number of thin films, quite similar in appearance
to the coats of the bladder. The quantity of fatty matter in this
Instance was by far too great to suppose it to have pre-existed in
the living body.
5. Powson of the Viper—From the experiments of Professor
Mangili, it appears that the poison of the viper may be swallowed
with impunity by animals, and that it preserves its poisonous
qualities even after being kept 26 months.—(Ann. de Chim. et
de Phys. iv. 169.)
6. Colouring Matter of the Blood.—Berzelius has published
an instructive paper on this subject. According to him, Vau-
quelin’s method of separating the colouring matter from blood
by means of sulphuric acid, is unnecessary, and does not answer
well. Berzelius’s method is very simple. Place the clot of
blood upon bloating paper, to get rid of the serum as completely
as possible ; then put the clot into water. The colouring matter
is dissolved, while the fibrmremains. By evaporating the water,
the colouring matter may be obtained in a separate state. No
iron can be detected in the colouring matter while undecomposed ;
but when reduced to ashes, about a half per cent of iron can
always be separated.—(Ann. de Chim. et de Phys. v. 42.)
7. Respiration of Tortoises.—Few animals are able to live for
any time when plunged under oil. Even those that can resist
the vacuum of an air-pump, or which revive after being drowned
in water, never revive if they have been kept for some time
under oil. The leech alone is capable of remaining for some
hours under oil with impunity. It appears from the experiments
of Carradori, that the land tortoise possesses the same remarkable
quality.. He kept one under oil for six hours. When he
appeared dead, he was taken out and exposed to the air, and
recovered. The same tortoise lived under oil for 24 hours. On
being taken out, he vomited a considerable quantity of oil ; but
died. Another tortoise lived 33 hours under oil; but was dead
in 36 hours.—(Ann. de Chim. et de Phys. v. 94.)
1818.] the Commencement of the Year 1817. Part I. 43
8. Urinary Calculus of a Horse-—Bucholz has lately sub-
jected a very remarkable calculus from a horse to a chemical
analysis. This calculus had a brownish green colour, was des-
titute of smell, but had a bitter taste. Its specific gravity was
1:07526. It was composed of concentric coats covering a
nucleus of hair’ From its chemical properties it seems very
similar to resin ; though it is distinguished from vegetable resin
by its insolubility in sulphuric ether, by the feeble action’ of
sulphuric acid on it, and by nitric acid converting it into Welter’s
bitter principle, and by some other characters of less importance.
When this calculus was burned to ashes, it left the following
substances : :
; Silica,
Phosphate of lime,
Carbonate of lime,
Alumina,
Oxide of iron,
Oxide of manganese, a trace,
Sulphate of lime, a trace.
(Schweigger’s Jour. xvii. 1.)
The preceding historical sketch, from the length of time that
has elapsed since the last was written, has extended to such a
length, that I have thought it nght to leave out most of the
apers which have already made their appearance in the
Annals of Philosophy.
(To be continued.)
Arricre I].
Biographical Sketch of Brisson.
Brisson was born at Fontenai, on April 3, 1723, and like
many others of his countrymen, who afterwards became distin-
guished for their scientific attamments, was originally destined
for the ecclesiastical profession. Early in life, however, he was
so fortunate as to attract the notice of Reaumur, from whom
he acquired a taste for natural history, and under whose auspices
he commenced his literary career, after he had renounced his
original destination. He was employed by his patron in the
arrangement of hiseabinet, and was induced to form a new
classification of the specimens, which was principally derived
from their external characters and most obvious qualities. He
afterwards determined to make a general application of the
method which he had employed in Reaumur’s cabinet ; and
beginning by the animal kingdom, he divided it into nine classes,
depending upon their greater or less resemblance to man. In
44 Biographical Sketch of Brisson. [Jury,
1756 he published the first two classes, the quadrupeds, and the
cetacea; the prevailing character of the work is simplicity, the
descriptions and the nomenclature are all marked by this quality,
-and the whole seems to have been intended to convey the
greatest possible quantity of information in the least assuming
manner. In 1760 the third part, the omithology, appeared, a
work that contained more original matter and more scientific
research, than the former, and tended to raise his character to a
higher rank as a naturalist. At this period, however, he had the
misfortune to lose his friend Reaumur, and from some cause,
with which we are not acquainted, Buffon and Daubenton, under
whose care Reaumur’s cabinet was placed, threw some obsta~
cles to his use of it, and by this means almost compelled him to
renounce his favourite pursuit.
Being thus deprived of his former occupation, he accepted an
offer, which was made him by the Abbé Nollet, to become his
assistant in the lectures on natural philosophy, which he deli-
vered in the college of Navarre. In this new situation, he
exerted all the energies of his mind upon experimental philo-
sophy, which had been before bestowed upon natural history ;
and he seemed to have experienced no diminution of his ardour
for science, by the change in the department to which he espe-
cially devoted himself. He published, in a succession of
memoirs, the results of his inquiries on various topics, of which
the most important is a paper which he presented to the Aca-
demy in 1772, on the specific gravity of metals. This was
afterwards expanded into a separate treatise on the subject,
which was published in 1787, and is said to have occupied his
attention for 20 years; it is generally admitted to possess the
merit of great accuracy in all its parts, and retains its estimation
as a work of standard value. Brisson was one of the most active
members of the commission that was formed in France to esta-
blish a new system of weights and measures ; and it is probable
that we are indebted to him for a considerable share of the merit,
both of the plan and of the execution, of the method that was
adopted. Besides his papers on individual subjects, he was the
author of an elementary treatise, anda dictionary of natural phi-
losophy, works of established reputation, which were extensively
eraployed in France, and have been translated into other lan-
guages. He died of an apoplexy in 1806, and has left behind
the well-earned reputation of an accurate and patient investigator
of science rather than of a profound theorist, or an ingenious
discoverer. What he aimed at he accompkghed ; accuracy was
his great object ; and hc was more desirous of becoming useful,
by removing obstacles in the road to knowledge, than of
attempting himself to enter upon any new or intricate paths.
His reputation with posterity will principally rest upon his
treatise on the specific gravity of metals.
6 .
1818.] Mr. Winch on the Geography of Plants. 45
Articte Ii.
On the Geography of Plants. By N. 1. Winch, Esq.
(To the Editors of the Annals of Philosophy.)
GENTLEMEN, -— Newcastle-upon-Tyne, May 4, 1818.
In January last I did myself the honour of transmitting to you
a a. on the distribution of vegetables indigenous in the north
of England; I now continue those observations hy some
remarks on the growth of native and exotic forest trees and
shrubs ; and hope next morfth to conclude this slight essay on
the geography of plants in our parallel of latitude, with a concise
account of the fruits that ripen, and species of grain which come
to perfection, at different heights in 55° North. By these data
the temperature of the climate and the nature of the soils may,
in some measure, be elucidated; but several meteorological
facts must be deferred till I have leisure and opportunities to
revise and correct my notes, which are not at present sufficiently
complete to lay before your scientific readers.
Of forest trees, the oak first claims our attention. In the
sheltered vales of Tyne, Derwent, and Tees, it attains to a
laree size, and may be considered truly indigenous ; for enormous
trunks and branches are dug out of all the peat mosses which
are not situated af a very considerable elevation above the levels
of the rivers; and this phenomenon occurs even among the
recesses of the Cheviot mountains, a district which is now des-
titute of oaks. In Weardale and Teesdale, trees of a stunted
growth may be traced to the elevation of 1,600 or 1,700 feet
above the level of the sea. The river Dal, in Sweden, in lat.
60° 30’ North, and Christiana, in Norway, in 59° 56’, appear to be
the northern limits of this valuable timber; but the oaks which
I have noticed on the banks of the Gotha, in lat. 58°, were of
very diminutive size. ;
The common elm of the southern counties of England
(Ulmus campestris) is certainly not indigenous north of the
Tees ; and, of course, I cannot help suspecting that the elm
mentioned by Von Buch as growing in the vicinity of Christiana,
and by Wahlenberg to the north of the Lake Venner, in Verm-
land, will prove to be the Wych elm (Ulmus montana), or
ay the smooth-leaved elm (Ulmus glabra of Eng. Bot.).
ven in sheltered plantations, the common elm does not attain
to a considerable size; but the Wych elm is abundant in every
hedge, and, together with the smooth-leaved elm, skirts our
moors at the height of 2,000 feet.
The beech (Fagus sylvestris) and aspen (Populus tremula) are
truly natives; but the former does not climb the hills to the same
height as the oak, but flourishes beautifully in the vales. Von
46 Mr. Winch on the Geography of Plants. [Juty,
Buch assigns the river Gotha as the northern boundary of the
beech, and the province of Halland, in Sweden, as that of the
aspen and black poplar (Populus nigra). Lightfoot doubts
whether either the white or black poplar are natives of Scotland
(see p. 616 and 618); nor have I ever seen these trees in @
natural wood in the north of England. The lime (Tilea europea),
the chesnut (Fagus castanea), and the hornbeam (Carpinus
Betulus), stand in the same predicament. ’
Large holly trees (Hex aquifolium) are among the chief orna-
ments of many woods in the county of Durham, as is the yew
(Taxus baccata) to the white calcareous cliffs im the romantic
Dene at Castle Eden. In Borrowdale, and on the margins of
the Cumberland and Westmorland lakes, the birch (Betula alba)
equals in size and beauty the birches of Norway and Sweden;
but it is not found on the mountains higher than the syca-
more (Acer Pseudo Platanus), which in these subalpine regions.
is quite at home. Here too may be seen the mountain ash
(Pyrus aucuparia); but the white beam (Pyrus aria) may be
traced fromthe High Force of Tees to the sea coast, provided the
soil rests upon limestone rocks. The alder (Alnus glutinosus)
and marsh elder (Viburnum opulus) accompany every stream,
and the hazle (Corylus avellana), black cherry (Prunus cera-
sus), bird cherry (Prunus padus), the spindle tree (Kuonymus
europeus), the raspberry (Rubus ideus), the common elder
(Sambucus nigra), are found in all the woods from the sea shore
to those situated at an elevation of ],600 feet ; but the common
maple (Acer campestris) occurs only in the hedges of the flat
country which surrounds Darlington.
The ash (Fraxinus excelsior) and white thorn (Mespilus oxy-
acantha), as well as the less useful crab tree (Pyrus malus) and
black thorn (Prunus spinosa), abound through the whole district ;
but the bullace tree (Prunus insititia) is extremely rare; and the
plumb tree (Prunus domestica), pear tree (Pyrus communis),
black and red currants (Ribes nigrum and R. rubrum), the
barberry (Rerberis vulgaris), and gooseberry (Ribes grossularia),
though now of frequent occurrence, I suspect were not originally
natives of the soil. The four following shrubs are certainly
indigenous: Ribes petreum, Ribes spicatum (rare), Ribes
alpinum, and Ligustrum vulgare; but Lonicera xylosteum,
which stands on the authority of Wallace, should be expunged
from our Flora.
On the elevated moors between Blanchland, at the head of the
Derwent, and Wolsingham, on the river Wear,* and even on the
mountains of Cross Fell, at an elevation of nearly 3,000 feet,
the roots and trunks of very large pines (Pinus sylvestris?) are
seen protruding from the black peat moss, being exposed to view
* This is the only spot in Britain where Gyrophora glabra of Acharius has
been detected in fructification,
4
0
1818.} Mr. Winch on the Geography of Plants. 47
by the water of these bogs having drained off and left the peat
bare; but this tree is no longer indigenous with us. And it
may be worthy of remark, that the Scotch fir does not at this
day attain the size of these ancient pines, though planted in
similar moorland situations, even though the young trees be
protected, and the plantations situated at a lower level. The
spruce fir (Pinus abies) appears never,to have been a native of
this island, though the woods on the continent of Europe, both to
the north and south of Britain, abound with it.
In lowland situations it is impossible to ascertain the native
from the exotic willows; but having remarked the blue willow
(Salix ccerulea) in the highlands of Scotland, I conclude it may
be indigenous here ; but I apprehend the golden willow (Salix
vitellina) has been brought to us from the south of Europe. On
the banks of our subalpine rivulets is the true locality of
Salix croweana, not in the hedges of Norfolk. (See Eng. Bot.)
The weeping willow, a native of Syria, never ripens its wood,
and of course never flowers in the north.
The furze (Ulex europzus), when it can no longer exist on open
exposed moors, may be found in sequestered Denes at a height
of 2,000 feet; here too terminates the growth of our most
common bramble (Rubus corylifolius), where it is all but an
evergreen, and where the fronds of many ferns survive the seve-
rity of our winters.
On the Fyall Alps, in Lapland, at 1,400 feet below the line of
perpetual snow, Wahlenberg noticed the following shrubs:
Salix glauca, Betula nana, Juniperus communis, Salix hastata,
Arbutus alpina, Andromeda ccerulea, Andromeda polifolia, and
Rubus chamzmorus ; and at 600 feet higher, Salix lanata, Salix
myrsinites, Azalea procumbens, Azalea lapponica, Vaccinium
uliginosum, and Empetrum nigrum. It may not be amiss to
compare these plants with those of a similar description found
at 2,000 or 3,000 feet elevation in this latitude: Salix glauca,
Betula nana, and Arbutus alpina, Salix myrsinites, Azalea pro-
cumbens, and Andromeda ceerulea do not reach us, though
natives of the Scotch highlands. Salix lanata and Azalea lappo-
nica are foreign to Britain; but Juniperus communis may be
traced from the coast to the highest mountains ; and Andro-
meda polifolia is comparatively speaking a lowland plant. Rubus
chamemorus flourishes on the Cheviots, on Cronkley Fell, and
other moors in Teesdale, together with Empetrum nigrum ;
but Vaccinium uliginosum does not attain to so great an eleva-
tion. In the place of Arbutus alpina, we have Arbutus uva ursi,
and of Salix Janata, a few scattered plants of Salix arenaria, on
the Teesdale hills ; and the summit of Skiddaw is covered with
Salix herbacea, but without its usual attendant, Salix reticulata.
Cistus marifolius and Dryas octopetala grow by the Black Ark
on the highest part of Cronkley.*
* This is also the habitat of Tofieldia palustris, a native of Lapland and North
48 Mr. Winch on the Geography of Plants. [Juny,
There appears something enigmatical in the causes which
affect the growth of many exotic shrubs well known in gardens
and plantations; for many natives of the north of Asia, Portu-
gal, Japan, and even South America, resist the severity of our
winters much better than many which are indigenous in Italy,
the south of France, and of Germany. The strongest instances
are those of the common myrtle, pomegranate, and oleander,
all of which, though European plants, perish at a temperature
no way injurious to the Rhododendron ponticum of Asia Minor;
this, as well as the Rhododendron maximum of North America, is
much more hardy than the bay, or even than the Portugal laurel.
The common laurel and bay never flower here, nor will the
strawberry tree (Arbutus unedo), Aucuba japonica, Pyrus japo-
nica, nor Buddla globosa of Chili, perfect their seeds. On the
other hand, the Provence rose of the South of France is found
every where, and the white rose (Rosa alba) is naturalized on
the shores of Tyne, yet Rosa sempervirens flowers but spar-
‘ingly, and the yellow rose (Rosa lutea) never flowers in the vici-
nity of Newcastle, but both flourish in the neighbourhood of
Hexham at a distance of 30 miles from the sea ; the three latter
are from Germany.* e
On the coast of Greece, Albania, and Daimatia, [have observed
the limestone rocks covered with the Mastic (Pistacia lentis-
cus) myrtle, rosemary, Laurus tinus, strawberry tree (Arbutus
unedo), and juniper. Of these, the first and second will not survive
our winters ; the third, fourth, and fifth, will not perfect their
fruit ; but the last ascends to the top of our highest mountains.
I shall now briefly notice such exotic trees as succeed best
with us in woods and plantations: the horse chesnut from the
north of Asia, Populus dilatata from Italy, Populus balsamifera,
P. monilifera, and P. angulata from North America, several
of the genus Pinus and of Quercus from the same country, the
larch and silver fir from the Alps, the spruce fir of the north of
Europe, and some of the American ashes ; but the Platanus
orientalis, P. occidentalis, Liriodendron tulipifera, the cork
and evergreen oaks, and cedar of Lebanon, thrive only in the
most sheltered situations and best soils.
N. I. Wincn.
America, which Dr. Smith has separated from the Swiss Tofieldia, which he has
named T, alpina (See Linn. Trans, vol. xii. p. 239). On the same mountainous
moors, Curex capillaris, a rare Lapland and Swiss species of Sedge, is likewise
met with. Cornus suecica should have been included among the Lapland plants in
the former part of this paper.
* For a brief account of the Roses of the district, see Monthly Magazine,
April, 1816.
1818.] Account of a Storm in Sussex. 49
ARTICLE IV.
Account of a Storm in Sussex in 1729.
’ Tue Editors have been favoured by Sir Joseph Banks with a
pamphlet, published in the year 1730, containing a narrative of
a very remarkable storm, that passed over a part of the counties
of Sussex and Kent, on May 20, in the preceding year. Except
in its much greater degree of violence, it appears to have borne
a very close resemblance to the hurricane of April 26, last, of
which Col. Beaufoy has given an account, published in the last
number of the Annals; and.as the pamphlet itself, as well as
the occurrence of which it treats, seem to have been nearly
forgotten, they conceive that a short abstract of it may not be
unacceptable to their readers.
The author, who signs himself Richard Budgen, begins by
detailing the state of the weather for some days previous to
May 20; after a succession of winds from a northerly point,
attended by a low temperature, on the 12th, the air suddenly
became much warmer, accompanied with southerly winds, and
continued so until the day of the storm. The following is the
account of the day itself: ‘“‘ The 20th, a slight flying tempest in
the morning, with a little scattering rain; the rest of the day
was very clear, and extremely hot and sultry ; wind south till
about five in the afternoon, when there began to appear a
haziness in the south, which, by degrees, with a vanishing edge,
arrived at our zenith about seven; when there began to appear
plain symptoms of a tempest. We distinctly heard the thunder
at eight, and had a prospect of two different tempests ; one came
over by Newhaven, Lewes, and Crowborrow, and scattered part.
of the shower upon us at Fraint, and Tunbridge-Wells ; the
other from Cuckmere-Haven, by Aldfriston, between Mayfield
and Burwash, to Wadhurst, &c. About nine, these storms
were passed over us into the north, and made an opening in the
south-east, where we had the surprising horror of seeing (at
about 20 miles distant) such unintermitting corruscations, toge-
ther with such dreadful darting and breaking forth of liquid fire,
at every flash of lightning (in the way of the hurricane from the
sea side into Kent), as, perhaps, has not been seen in this climate
for many ages.”
The storm commenced its ravages at the sea side, near Bex-
hill, in the eastern part of Sussex, and advanced nearly in a
straight line, and in a direction a little to the east of north,
across the country to Newenden, in Kent: here its fury was
considerably abated ; it was again more violent a few miles fur-
ther, but seems shortly afterwards to have been entirely
dispersed. Its breadth was well defined, and comparatively
limited ; for the first two miles it was no more than 30 rods,
Vou. XII. N°'T. D
50 Account of a Storm in Sussex. [Jury,
but afterwards it increased to more than double that width. The
distance to which it extended in its extreme violence was about
12 miles, and in this space its ravages were almost inconceiv-
ably violent; buildings of all descriptions, and many hundred
trees, were instantly swept down and whirled in all directions.
Its motion appears certainly to have been in a spiral direction,
and from the right hand to the left, or contrary to the course of
the sun; for it was observed that all bodies “ drove down near
the eastern verge towards the north, and nearthe western towards
the south.” With respect to its velocity, the author states that
“ the distance from the sea side to Newmgden-Level is about 12
miles, which it passed over in 20 minutes ; and if we take 70
rods for the mean diameter of the vertiginous motion, the dura-
tion of the offensive wind could not exceed 20 seconds......
According to this computation, the direct velocity of the storm
is 42 feet in a second, to which adding 43 feet for the increase
by the vertiginous or spiral motion, makes 85 feet ; whichis the
space run through in every second of time near the outward verge
of the gyration, and the velocity by which all obstacles received
the impulse of the wind.” Although it raged with so much
violence in its progress along the track which it pursued, it
appears to have been completely limited to this space ; for in
passing over woods, where it tore the largest trees into frag-
ments, others that were in the neighbourhood suffered no injury,
and “had not the least appearance of a storm by twigs or
leaves blowed off; ” there does not seem to have been any wind
out of the direction of the hurricane ; and as it proceeded across
the country, its whole fury, in each particular spot, was over in
perhaps half a minute. One of its most remarkable effects was
that of raising up heavy bodies from the ground, and transporting
them to considerable distances. In this way, large pieces of
timber, and even portions of the roofs of houses, were carried
many yards, and some bulky substances were entirely lost. A
remarkable instance is related of this kind of transportation,
where a cottage was destroyed in consequence of “a large apple
tree brought out of a neighbow’s orchard, over three hedges,
with the roots and earth about them, that fell upon the house.”
It is said that the storm generally raged with the greatest
violence in gills or narrow valleys, that hada considerable decli-
vity on each side, and upon the highest ground. Its breadth
was also increased as it ascended to the tops of the hills, which
gives us reason to suppose, as the author remarks, that the body
of the hurricane was in the form of an inverted truncated cone ;
while its power of raising up heavy bodies would indicate that
there was a partial vacuum in the central part of the cone, which,
if it had occurred on the sea, would have produced the pheno-
mena of a waterspout. The pamphlet contains a good deal of .
theoretical reasoning on the cause of the hurricane, derived from
the erroneous opinions that were then prevalent; but with
>
PPE PTO, y
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Pl IXXX7 Pagedl.
In? & Philip Leevlor
Engraved jor D7 Thomson's Anrvals_for Baldwin, Cradock, & Joy Paternoster Row, Tay, LAS
1818.] Construction of Fire-places to Steam Boilers. 51
respect to the correctness of the facts, there is strong internal
evidence for placing great confidence in them. It is accompa-
nied by an accurate map, in which the course of the hurricane is
noted, and all the woods and houses marked on which it wrecked
its fury.
-ARTICLE V. é
On the Construction of Fire-places to Steam Boilers. By John
and Philip Taylor, Civil Engineers.
72, Upper White Cross-street,
GENTLEMEN, May 6, 1818.
Tue annexed sketch exhibits the construction which we have
lately used in the erection of fire-places to steam boilers, and
which seems to combine some advantages, so as, perhaps, to
render it worthy a place in your journal ; at the same time we are
aware that there is little in it that can be called absolutely new.
We were desirous in the first place to remove the fuel from the
possibility of actual contact with the bottom of the boiler, which
sometimes happens from the carelessness of the men, and stillmore
to avoid, if possible, the injury accruing from the sudden influx of
large portions of cold air from frequent opening of the fire door.
The contraction caused by this sudden diminution of the heat, is
apt, in some cases, to disturb the joints of the plates, where high
ae of temperature are used, and to render them leaky.
e have avoided both these evils, by removing the fire from
under the bottom of the boiler, and placing it, as in the drawing,
in a furnace, at one end, whence the flame reverberates
through a flue passing under tke vessel to be heated. As the
cold air, which may at times be admitted, comes first into
immediate contact with a mass of heated brickwork, and is
mixed before it passes through the opening into the flue, by
which the whole is, as it were, wiredrawn together, and so
united as to render the changes, of temperature more gradual.
The front of the furnace is provided with an inclined hopper,
as shown in Plate LX XXI, which is to be kept full of coal at all
times, preventing the passage of any air that way, and the
fuel may be occasionally pushed forward into the furnace with-
out much breaking through it, This mode of feeding boiler
fire-places bas been used before, and with advantage, and parti-
cularly where the coal is of sucha quality as not to cake much,
in which case it has been found that it supplies the consumption
for a long time with very little trouble, and without the admission
of cold air. With Newcastle coal it will not go on so regularly,
but acts very well with a little assistance.
The hopper is made of cast iron ;, but the lower part of it,
D 2
32 Construction of Fire-places to Steam Boilers. [Jury,
which is in contact with the fire, is terminated by Welch or
Stourbridge lumps. Under it a small door is placed, which
serves to permit the introduction of a bar to break up the fire
occasionally, or to cut out the clinkers.
The furnace is further provided with apertures for the intro-
duction of air, so as to consume the smoke, the situation of
which may be observed in the two sections. In the lateral one
may be seen where two enter the furnace on one side; the
number may of course be increased at the option of the builder ;
and in the transverse section, the mode of conducting the air
is exhibited.
_ It has been very judiciously observed that when cold air is
admitted in a direction parallel to the current of the smoke, it
frequently passes with it into the chimney without inflaming it,
the two streams running as it were together without mixing in
such a manner as is required to produce the effect. To have
the inflammation complete, the air should be as hot as possible,
by which also the least check is given to the action of the fire,
and the current should cross that of the smoke where they meet,
by which such a mixture of the two is produced as is required
for the intended purpose.
The air in this furnace is first admitted by small passages in
its sides, which are fitted with registers, and passes horizontally
so as to strike against the back of the fire-bricks lining the fire-
place, behind which it rises until it is turned through small aper-
tures into the furnace. The vertical passages may be extended
considerably in a lateral direction, so as to present a great heating
surface to the air, which also will serve to increase the durabi-
lity of the fire-bricks by keeping them cooled at the back. The
air enters so as to cross the current of the draft ; and the opening
into the fire is so made as to direct the influx towards the centre,
and to prevent it from striking the arch, which otherwise would
be injured by it. The quantity of air is regulated at pleasure by
the registers ; and it is obvious that it will always pass into the
fire in a heated state, which seems to be essential to the speedy
inflammation of the smoke. Weare, &c. &c.
JoHN AND Puitie TayLor.
Description of the Plate.
Fig. 1. Lateral section, showing the furnace or fire-place, and
one end of a long steam boiler, under which the flame passes
through a semicircular flue to the chimney at the other end.
A, fire-place.
B, ash-pit.
C, throat of the furnace.
D, flue under the boiler.
_ E, the boiler.
a, the hopper for coals.
1818.] Observations on the River Zaire. 53
6, door for stoking.
cc, passages for heated air to consume the smoke.
Fig. 2. Transverse section, in which the same letters refer to
the same parts as in Fig. 1.
dd, entrances for air to inflame the smoke.
ee, vertical passages behind the linings of the fire-place
through which the air ascends and becomes heated.
ArticLe VI.
Observations on the River Zaire. Collected from the Journals
of Capt. Tuckey and Prof. Smith.
AurHoucu the first view of the river Zaire convinced thé
gentlemen who had undertaken to explore it, that its magnitude
had been very much exaggerated, still it was found to be a
considerable stream, perhaps the most so of any of the African
rivers which discharge themselves into the Atlantic. The depth
of the river at its mouth appears indeed to be very great, as a
common sounding line of 160 fathoms did not reach the bottom ;
but its extreme breadth was scarcely three miles, and its velocity,
concerning which such wonderful accounts had been received,
was never more than five knots an hour, and often not more than
two and ahalf. It had been asserted that the mver was always
in a state of full flood; and on this fact had been principally
founded the hypotheses of its being the embouchure of the
Niger, or atleast of its extending up into the heart of the conti-
nent beyond the equator ; this, however, was found to be erro-~
neous, as during the short stay which the expedition made in the
country, they observed the swell of the water distinctly to com-
mence in the beginning of September ; and from ail the inform-
ation which they could obtain, they were led to conclude that,
with respect to its periodical floodings, it did not materially
differ from the other tropical rivers. The report that its stream
was so powerful as entirely to resist the effect of the tide appeared
to be equally incorrect. Near the mouth of the river, its banks
are low, and formed of alluvial earth; they are covered with
impenetrable thickets of a luxuriant vegetation of the mangrove,
and other plants of similar habits, and the stream is frequently
divided into several channels by low swampy islands. The loose
texture of the banks of the river causes perpetual changes in the
line of the coast and the direction of the currents, and frequently
small fragments of the matted turf are detached and float down
the stream, with the cyperus and other gramineous plants still
remaining upon them. These, which appear to have been very
inconsiderable in size, were magnified by the Portuguese into
54 Observations on the River Zaire. [JuLy,
floating islands, torn off from the main land by the violence of
the torrent, and suspended by its velocity. Beyond the alluvial
ground, the country rises into rounded hills of moderate height,
which are represented as being generally barren, and the whole
district seems to be but thinly peopled. On account of the dif_i-
eulty ofthe navigation, depending partly upon the irregularity of
the sea breezes, which were scarcely sufficient to counteract the
force of the stream, and still more from the winding and uncer-
tain course of the bed of the river, the large vessel proceeded only
as far as Embomma, a slave mart belonging to-the Portuguese,
which is the principal settlement in the country, about 80 or 90
miles from the sea. For a distance of 50 or 60 miles further, the
river still continues to be navigable, but it is considerably con-
tracted in its dimensions, and the hills approach so near to each
other, as in some places to leave only narrow strips of soil, and
in others, to come to the water’s edge. They are described as
bare and rocky, chiefly composed of mica slate, with masses of
quartz rising above the surface. In the little valleys between
the hills, there is more of the appearance of fertility; but the
whole district appears to have been barren and uninteresting.
The climate is represented as pleasant, the thermometer seldom
exceeding 76° in the day, or descending below 60° in the night ;
the atmosphere was generally serene, and the diurnal changes
uniform. In the morning there are light breezes from the 8.; and
for some hours in the middle of the day or afternoon, there is a
regular sea breeze.
The dreariness of the country increased as the travellers
advanced into the interior. Capt. Tuckey remarks, ‘“ the most
striking features of the country are the extreme barrenness of the
hills near the river, the whole being still composed of slate with
masses of quartz and sienite, the latter becoming the main
formation, as we advanced to the S8.E. with perpendicular
fissures from three inches to one quarter inch in breadth filled
with quartz.’ The bed of the river continues to contract in its
dimensions, and all navigation, even for canoes, becomes at
length impracticable, and remains so for about 40 miles. The
water was here not more than from 300 to 500 yards broad ; its
current necessarily becomes rapid, is broken into whirlpools by
rocks, while the banks are in many parts almost perpendicular,
and rise up to a great height. Besides a succession of smaller
rapids, there is a larger one in this part, which is spoken of by the
natives as a prodigious cataract. When the travellers saw it,
which, however, was just before the commencement of the rainy
season, “ they were not less surprised than disappointed, mstead
of a second Niagara, which the description of the natives, and
their horror of it, had given us reason to expect, to find a compa~
rative brook bubbling over its stony bed.” Perhaps in the
flooded state of the river, this rapid, which is called the fall of
Yellala may correspond more nearly with the description which
1818.] Morphium and Meconic Acid. 55
the natives gave of it. At all times, however, it is quite suffi-
cient to put an entire stop to all navigation; and besides this
particular obstacle, the stream is, in this part of its course, full
of eddies and whirlpools, and in some places darts along with
very great velocity, The fall of Yellala is formed by a succession
of ridges of micaceous slate, that cross the stream in an oblique
direction ; the rocks on both sides the fall are very steep, and
the mica slate, which is here undulating, abounds with veins of
quartz and compact feldspar.
After passing this long, rocky defile, the river again expands to
a breadth nearly equal to that of its mouth, the banks become
picturesque and beautifully varied, assuming the appearance of
a succession of lakes, while the country itself seemed to be much
improved in fertility. It is remarkable that from the mouth u
to this point, the Zaire does not receive a single branch of the
least consequence. Here the labours of the party terminated ;
and respecting the source of the Zaire, we are left entirely to
conjecture, as the reports that they were able to collect from the
natives were perfectly vague, and not in the least to be depended
upon. As to the hypothesis of the Zaire being the continuation
of the Niger, we confess that the general impression produced
on our minds is completely adverse to it; for although the
Zaire, as it passes through the kingdom of Congo, is a river of
considerable magnitude, it appears in the higest degree impro-
bable that the stream which Park saw at Sego should not have
received a greater accession after travelling some hundreds of
miles. If the expedition to Congo can be considered as throw-
ing any light upon the curious problem of the termination of the
iger, we should be disposed to say that it has done so, in as
much as it proved this river not to be identical with the Zaire.
EEG SS ER A a
ARTICLE VII,
Morphium and Meconic Acid.*
In the number of the Annals for June, 1817, we gave some
account of the properties of the first of these substances, to
which we shall now add a few more particulars. Many chemists
had endeavoured to analyze opium, and M. Derosne, whose
account appeared in vol. xlv. of the Ann. de Chimie, was sup-
posed to have detected the principle on which its specific
properties depend. By a succession of solutions, crystalliza-
tions, and distillations, he procured a crystallizable body, which
appeared to form a proximate principle of the opium, and to be
* Abridged from Ann, de Chim, t, v. and Journal de Pharm. for Oct, 1817,
56 Morphium and Meconic Acid. {Juny,
in an uncombined state, to which he gave the name of the
essential salt of opium. It possessed the narcotic properties of
this substance in a high degree, and in its chemical relations
partook of the nature of a resin.
The examination of opium has been. more lately undertaken
by M. Sertuerner, and the results of his experiments have been
considerably different from those of M. Derosne, or rather he
has carried his researches to a greater degree of minuteness, so
as to have detected in opium what seem to be two new vegetable
principles, one the morphium, which possesses many characters
of an alkali, the other, a new vegetable acid, to which he gives
the name of the meconic acid. To procure morphium, the
extract of opium is digested in acetic acid, or even in warm
water, ammonia is added in excess, and the morphium is preci-
pitated. It is, however, united to a quantity of extract and
meconic acid, to deprive it of which it is dissolved in diluted
sulphuric acid, and again precipitated by ammonia; it may be
still further purified by alcohol. For the leading characters
of morphium and its combinations with the acids, we shall
refer our readers to the account which we have already given
of it, and shall now proceed to the meconic acid. This sub-
stance was entirely overlooked by M. Derosne in his examina-
_ tion of opium; M. Sertuerner procured it by the following
process. After precipitating the morphium from a solution of
opium by ammonia, he adds to the residual fluid a solution of
the muriate of barytes ; a precipitate is in this way formed which
is conceived to be a quadruple compound of barytes, morphium,
extract, and the meconic acid. The extract is removed by
alcohol, and the barytes by sulphuric acid, when the meconic
_acid is left merely in combination with a portion of the morphium,
and from this it is purified by successive solutions and evapora-
tions. The acid when sublimed forms long colourless needles ;
it has a strong affinity for the oxide of iron, so as to take it from
the muriatic solution, and form with it a cherry-red precipitate ;
it also forms a crystallizable salt with hme, which is not decom-
posed by sulphuric acid; and what is of importance, it seems to
possess no particular power over the body when received into
the stomach. The essential salt of oprum obtained by M. De-
rosne is conceived to have been the meconate of morphium, 1. e.
a compound of the two new principles contained in opium.
The two new substances have been examined by M. Robi-
ae and M. Vogel. M. Robiquet, in order to discover whether
the morphium owed any of its peculiar characters to a portion
of ammonia still adhering to it, substituted magnesia tor the
- ammonia ; but he procured morphium by this process of the same
nature as in the former ; it exhibited an equally, or even a more
decisive alkaline character. M. Robiquet employed a more
effectual method of procuring the meconic acid than that
1818.} Morphium and Meconic Acid. 57
employed by Sertuerner ; it consisted essentially in treating the
opium with magnesia, in order to extract the morphium, when
the meconate of magnesia is formed at the same time. The
magnesia is removed by adding the muriate of barytes, and the
barytes is afterwards removed by diluted sulphuric acid. The
operation is more complicated than the one employed by
M. Sertuerner, but the meconic acid is procured in much larger
proportion.
Yhe meconic acid is stated to be very soluble both in alcohol
and in water; it does not seem to precipitate the oxides of iron
as M. Sertuerner conceived, although it gives a bright red colour
to the solutions of iron, nor does it appear to form combinations
with the oxides of copper or mercury ; but with potash, soda,
and lime, it forms crystallizable salts. M. Robiquet, in oppo-
sition to the opinion of M. Sertuener, conceives that the salt
obtained by M. Derosne is not the meconate of morphium ; but
he does not inform us what is the constitution of this substance.
M. Vogel observes that morphium may be obtained in larger
quantity if the opium be dissolved in acetic acid than in water,
and finds that it possesses the same properties whatever alkali or
alkaline earth we employ for its precipitation. He obtained the
meconic acid by precipitating the residual fluid after the removal
of the opium by the nitrate of barytes ; it was then digested
with alcohol, and afterwards treated with diluted sulphuric acid.
Brown crystals are deposited, consisting of the acid in an impure
state; they may be purified by sublimation, but the quantity
thus procured is very small; it may be obtained more copiously
by dissolving them in hot water and causing them to crystallize
a second time. The power which the meconic acid possesses
of reddening the solutions of iron is so great as to render it even
a more delicate test for this metal than the prussiate of potash.
Upon the whole there seems no reason to doubt the general cor-
rectness of M. Sertuerner’s results, that opium contains two pecu-
har vegetable prieiples ; that one of them is of an alkaline and
the other of an acid nature, and that the former is the body which
is the vehicle of the narcotic part of this substance. The only
circumstance that seems to be wanting to remove all doubt
respecting so remarkable a fact as that of the discovery of a new
alkali, is that the alkali or alkaline earth, which is employed in
the process, should be afterwards completely recovered or
accounted for, so as to remove all doubt respecting the possibility
of a portion of it still adhering to the adibieh and giving it its
suppoeed alkaline properties.
58. Mr. Gill on softening and hardening Steel. [Juur,
ArTicLe VIII.
On softening Steel by heating and quenching it, and on the hard-
ening and tempering tt at one Operation. By.Thomas Gill, Esq.
(To the Editors of the Annals of Philosophy.)
No. 11, Covent Garden Chambers,
GENTLEMEN, * June 15, 1818,
I HAVE now the pleasure of communicating for insertion in
your Annals, the above two processes on steel; and which, to
artisans in general, may seem to be impossibilities, being so very
different to the general practices ; but which, nevertheless, can
be readily performed under proper management, and possess
very considerable advantages over the ordinary methods.
It is well known that unless steel be heated to the proper
degree, it will not harden on being quenched in water, or other
proper fluid ; but it has escaped the general observation, that
steel heated rather below the hardening point and quenched will be
softened thereby, and in a much superior manner than by the
usual methods of annealing it, insomuch that it can be more
readily filed, turned, &c. and is entirely free from pins or hard
spots; and as it is not at all liable to be injured by this process,
and can be softened thereby in a much shorter time than by
annealing it, so it ought to be universally adopted.
Steel springs are usually hardened and tempered by two
distinct operations, being first heated to the proper degree, and
hardened by quenching in water, oil, &c. and then tempered,
either by rubbing them bright and heating them till they acquire
a pale blue or grey colour, or by burning or blazing off the
oil, &c.
It is, however, now found that both operations may be advan-
tageously performed at once, in the following manner :
The steel being heated to the proper degree, is to be plunged
into a metallic bath composed of a mixture of lead and tin, such
for instance as plumbers’ solder, and which is heated by a proper
furnace, to the tempering degree, as indicated by a pyrometer
or thermometer placed in the bath, when the steel will be at once
hardened and tempered, and with much less danger of warping or
cracking in the process than if treated in the usual way.
It would be a further improvement to heat the steel in a bath
of red-hot lead to the proper degree for hardening, previous to
quenching and tempering it in the other metallic bath, as it
would thereby be more uniformly heated, and be in less danger
of oxidation ; and, indeed, it is an excellent method of heating
steel, either for softening it, as in the first described process, or
for hardening and tempering it at once, as in the last mentioned
one, or even for hardening it in the usual method.
eo
1818.] History of Dr. Brewster’s Kaleidoscope 59
Hoping these suggestions will lead to the improvement of the
articles made of steel, and that they may also induce other per-
sons, who may be possessed of processes not generally known,
to communicate them through your channel for the public good,
I have the pleasure to remain, Gentlemen,
Your most obedient servant,
Tuomas GILL.
ArTICLE IX.
History of Dr. Brewster's Kaleidoscope, with Remarks on its
supposed Resemblance to other Combinations of plain Mirrors.
From a Correspondent.*
As this instrument has excited great attention, both in this
country and on the Continent, the readers of the Annals will doubt-
less take some interest in the history of the invention. -In the
year 1814, when Dr. Brewster was engaged in experiments on
the polarization of light by successive reflections between plates
of glass, which were published in the Phil. Trans. for 1815, and
honoured by the Royal Society of London with the Copley medal,
the reflectors were in some cases inclined to each other, and he
had occasion to remark the circular arrangement of the images
of a candle round a centre, or the multiplication of the sectors
formed by the extremities of the glass plates. In repeating, at
a subsequent period, the experiments of M. Biot on the action of
fluids upon light, Dr. B. placed the fluids in a trough formed by
two plates of glass cemented together at an angle. The eye
being necessarily placed at one end, some of the cement which
had been pressed through between the plates appeared to be
arranged into a regular figure. The symmetry of this figure
bemg very remarkable, Dr. B. set himself to investigate the
cause of the phenomenon ; and in doing this he discovered the
leading principles of the kaleidoscope. He found that in order
to produce perfectly beautiful and symmetrical forms, three con-
ditions were necessary.
1, That the reflectors should be placed at an angle, which
* In the Jast number of the Annals (p. 451), we inserted some remarks upon
the kaleidoscope, » ore especially concerning its discovery by Dr. Brewster, and
the circumstances in which it essentially differs from those instruments that have
been supposed to bear a general resemblance to it. The subject is so generally
interesting, that we do not hesitate to present to our readers a second and more
extended communication on the same topic, in which the history of the discovery is
more minutely traced, and the differences more fully detailed between the kalei-
doscope and the apparatus described by Bradley, We have omitted the letter
from Prof. Playfair to Dr. Brewster, as it had already appeared in the Annals,
retaining only the postcript; and we have also curtailed the article in some other
parts, which seemed of less importance.
60 History of Dr. Brewster's Kaleidoscope. [Juuy,
was an even or an odd aliquot part of a circle, when the object
was regular; or the even aliquot part of a circle when the object
was irregular.
2. That out of an infinite number of positions for the object’
both within and without the reflectors, there was on/y one position
where perfect symmetry could be obtamed, namely, by placing
the object in contact with the ends of the reflectors.
3. That out of an infinite number of positions of the eye,
there was only one where the symmetry was perfect, namely, as
near as possible to the angular point, so that the circular field
could be distinctly seen; and that this point was the only one
out of an infinite number at which the uniformity of the light of
the circular field was a maximum.
Upon these principles Dr. B. constructed an instrument, m
which he fixed permanently across the ends of reflectors pieces
of coloured glass, and other irregular objects, and he showed
the instrument in this state to some members of the Royal
Society of Edinburgh, who were much struck with the beauty of
its effects. In this case, however, the forms were nearly perma-
nent, and a slight variation was produced by varying the position
of the instrument, with respect to the hght. The great step,
however, towards the completion of the instrument remamed yet
to be made; and it was not till some time afterwards that the
idea occurred to Dr. B. of giving motion to objects, such as preces
of coloured glass, &c. which were either fixed or placed loosely in a
cell at the end of the instrument. When this idea was carried into
execution, the kaleidoscope, in its simple form, was completed.
In this state, however, the kaleidoscope could not be consi-
dered as a general philosophical instrument of universal applica-
tion ; for it was incapable of producing beautiful forms unless the
object was nearly in perfect contact with the end of the reflectors.
The next, and by far the most important step of the invention,
was therefore to remove this limitation by employing a draw
tube and lens, by means of which beautiful forms could be
created from objects of all sizes, and at all distances from the
observer. In this way the power of the kaleidoscope was indefi-
nitely extended, and every object in nature could be introduced
into the picture in the same manner as if these objects had been
reduced in size, and actually placed at the end of the reflectors.
When the instrument was brought to this state of perfection,
Dr. Brewster was urged by his friends to secure the exclusive
property of it by a patent ; and he accordingly took out a patent
for “ A New Optical Instrument for creating and exhibiting
beautiful Forms.” In the specification of his patent he describes
the kaleidoscope in two different forms. The first consists of
two reflecting planes, put together according to the principles
already described, and placed in a tube, with an eye-hole in the
particular position which gives symmetry and a maximum uni-
formity of light, and with objects such as coloured glass, placed
1818.] History of Dr. Brewster’s Kaleidoscope. 61
in the position of symmetry, and put in motion either by a rotatory
movement, or by their own gravity, or by both combined. The
second form of the instrument, described in the specification,
is when the tube containing the reflectors is placed in a second
tube, at the end of which is a convex lens which introduces into
the picture objects of all magnitudes, and at every distance, as
has been already described.
After the patent was signed, and the instruments in a state of
forwardness, the gentleman who was employed to manufacture
them under the patent, carried a kaleidoscope to show to the
principal London opticians, for the purpose of taking orders
from them. These gentlemen naturally made one for their own
use, and for the amusement of their friends ; and the character
of the instrument being thus made public, the tinmen and glaziers
began to manufacture the detached parts of it, in order to evade
the patent; while others manufactured and sold the instrument
complete, without being aware that the exclusive property of it
had been secured by a patent.
In this way the mvasion of the patent right became general
among that class of individuals against whom the law is seldom
enforced but in its terrors. Some workmen of a higher class
were encouraged to piracy by this universal opposition to the
patent ; but none of the respectable London opticians would
yield to the clamours of their customers, to encroach upon the
rights of an inventor, to whom they were at least indebted for a
new and a lucrative article of trade. ;
In order to justify these piratical proceedings, it became
necessary to search out some combinations of plain murrors,
which might be supposed to have some resemblance to Dr.
Brewster’s instrument ; and it would have been strange indeed
if some theorem or experiment had not been discovered, which
could have been used to impose upon the great crowd who are
entirely ignorant of the principles and construction of optical
instruments. There never was a popular invention which the
labours of envious individuals did not attempt to trace to some
remote period; and in the present case so many persons had
hazarded their fortunes and their characters, that it became
necessary to lay hold of something which could be construed into
an anticipation of the kaleidoscope.
The first supposed anticipation of the kaleidoscope was found
in Prop. XIli. and X1V. of Professor Wood’s Optics, where
that learned author gives a mathematical investigation of the
number and arrangement of the images formed by two reflectors,
either inclined or parallel to each other. This theorem assigns
no position either to the eye or to the object, and does not even
include the principle of inversion, which is absolutely necessary
to the production of symmetrical forms. The theorem is true,
whatever be the position of the object or of the eye. 1m order to
put this matter to rest, Dr, Brewster wrote a letter to Professor
62 History of Dr. Brewster’s Kaleidoscope. [Juuy,
Wood, requesting him to say if he had any idea of the effects of
the kaleidoscope when he wrote those propositions. To this
letter Dr. B. received the following handsome and satisfactory
answer :
« St. John’s, May 19, 1818.
«¢ Sir,—The propositions I have given relating to the number
of images formed by plane reflectors inclined to each other,
contain merely the mathematical calculation of their number and
arrangement. The effects produced by the kaleidoscope were never
in my contemplation. My attention has for some years been
turned to other subjects, and I regret that I have not time to
read your Optical Treatise, which | am sure would give me great
pleasure. I am, Sir, your obedient humble servant,
“J. Woop.”
The next supposed anticipation of the kaleidoscope was an
instrument proposed by Mr. Bradley in 1717. This instrument
consists of two ra pieces of silvered looking-glass, five inches
wide and four inches high, jointed together with hinges, and
opening like a book. These plates being set upon a geometrical
drawing, and the eye being placed in front of the mirrors, the
lines of the drawing were seen multiplied by repeated reflections.
This instrument was described long before by Kircher, and did
not receive a single improvement from the hands of Bradley. It
has been often made by the opticians, and was principally used
for multiplymg the human face, when placed between the
mirrors ; but no person ever thought of applying it to any pur-
pose of utility, or of using it as an instrument of rational amuse-
ment, by the creation of beautiful forms. From the very
construction of the instrument, indeed, it is quite incapable of
producing any of the singular effects exhibited by the kaleido-
scope. It gives, indeed, a series of reflected images arranged
round a centre; but so does a pair of looking-glasses placed
angularly in an apartment, and so do the pieces of mirror glass
with which jewellers multiply the wares exhibited at their
windows. It might, therefore, be as gravely maintained that
any of these combinations of mirrors was a kaleidoscope, as that
Bradley’s pair of plates was an anticipation of that instrument.
As the similarity between the two has been maintained by
ignorant and interested individuals, we shall be at some pains to
explain to the reader the differences between these two instru-
ments ; and we shall do this, first, upon the supposition that the
two instruments are applied to geometric lmes upon paper.
1. In Bradley’s instrument, 1. In the kaleidoscope, the
the length is less than the length of the plates must be
breadth of the plates. four, or five, or six times their
breadth.
2. Bradley’s instrument can- 2. The kaleidoscope cannot
not be used with a tube. be used without a tube.
1818.]
3. In Bradley’s instrument,
from the erroneous position of
the eye, there is a great inequa-
lity of light in the sectors, and
the last sectors are scarcely
visible.
4. In Bradley’s instrument,
the figure consists of elliptical,
and consequently unequal sec-
tors.
5. In Bradley’s instrument,
the unequal sectors donot unite,
but are all separated from one
another by a space equal to the
thickness of the mirror glass.
6. In Bradley’s instrument,
the images reflected from the
first surface interfere with those
reflected from the second, and
produce a confusion and over-
lapping of images entirely. in-
consistent with symmetry.
7. In Bradley’s instrument,
the defects in the junction of
the plates are all rendered visi-
ble by the erroneous position of
the eye.
History of Dr. Brewster’s Kalecdoscope.
63
3. In the kaleidoscope, the
eye is placed so that the uni-
formity of light is a maximum,
and the last sectors are dis-
tinctly visible.
4. In the kaleidoscope, all
the sectors are equal, and
compose a perfect circle, and
the picture is perfectly sym-
metrical.
5. In the kaleidoscope, the
equal sectors all unite into a
complete and perfectly symme-
trical figure.
6. In the kaleidoscope, the
secondary reflections are en-
tirely removed, and therefore
no confusion takes place.
7. In the kaleidoscope, the
eye is placed so that these
defects of junction are invi-
sible.
The reader will observe, that in this comparison the two
instruments are supposed to be applied to geometric lines upon
paper, and that this was the only purpose to which Bradley ever
thought of applying his mirrors ; yet the kaleidoscope is in every
respect a superior instrument, even for that inferior purpose, and
gives true symmetrical forms, which the other instrument is
incapable of doing.
In the comparison which has now been made, we have
degraded the kaleidoscope by contrasting its effects with those
which Bradley’s instrument is capable of producing, for these
effects are not worth the looking at. When we attempt to
employ Bradley’s instrument to produce the effects which have
been so much admired in the kaleidoscope, namely, to produce
beautiful forms from transparent or opaque-coloured objects
contained in a cell, and at the end of the reflectors it fails so
entirely that no person has succeeded in the attempt. It is
indeed quite impossible to produce by it the beautiful and
symmetrical forms which the kaleidoscope displays. Had this
been possible, Dr. Brewster’s patent might have been invaded
with impunity by every person who chose to manufacture Brad-
64 History of Dr. Brewster’s Kaleidoscope. [Juuy,
ley’s instrument; but this was never tried,* and for the best of
ll reasons, because nobody would have purchased it.
We trust that no person, who wishes to judge of this subject
with candour, will form an opinion without having actually seen
and used the instrument proposed by Bradley. Let any person
take Bradley’s plates, and, having set them at an angle of 30° or
221°, ace them upon a cell containing fragments of coloured
glass, he will infallibly find that he cannot produce a picture of
any symmetry or cage The disunion of the sectors, the
darkness of the last reflections, and the enormous deviation
from symmetry, towards the centre of the figure, will convince
him, if he required conviction, that the instrument is entirely
useless as a kaleidoscope. To those, however, who are not
capable, either for want of knowledge or want of time, to make
such a comparison, we may present the opinion of three of the
most eminent natural philosophers of the present day, viz. the
celebrated Mr. Watt, Professor Playfair, and Professor Pictet.
“‘ It has been said here,” says Mr. Watt, “that you took the
idea of the kaleidoscope from an old book on gardening. My
friend, the Rey. Mr. Corrie, has procured me a sight of the
book. It is Bradley’s Improvements of Planting and Gardening.
London 1731, part 2, chap. i. It consists of two pieces of look-
ing glass of equal bigness, of the figure of a long square, five
inches long and four inches high, hinged together, upon one of
the narrow sides, so as to open and shut like the leaves of a
book, which, being set upon their edges upon a drawing, will
show it multiplied by repeated reflections. This mstrument 1
have seen in my father’s possession 70 years ago, and frequently.
since ; but what has become of it I know not. In my opinion,
the application of the principle is very different from that of your
kaleidoscope.”
Postcsript to Prof. Playfair’s Letter. (or the Letier itself, see
Annals, xi. 451.)
“ P. §.—Granting that there were a resemblance between the
kaleidoscope and Bradley’s instrument, in any of the particulars
mentioned above, the intreduction of coloured and moveable
objects, ‘at the end of the reflectors, is quite peculiar to Dr.
Brewster’s instrument. Besides this, a circumstance highly
deserving of attention, is the use of two lenses and a draw tube,
so that the action of the kaleidoscope is extended to objects of
all sizes, and at all distances from the observer, and united, by
that means, to the advantages of the telescope. JPRS
* Yn illustration of this argument, we may state the following fact. Mr. C. of
Birmingham, being anxious to evade Dr. Brewster's pateut, ata time when the
manufacture of the patent kaleidoscope was inthe hands of another person, attempt-
ed to construct instruments in imitation of Bradley’s. After exercising his ingenuity
for some time, he abandoned the attempt as impracticable, and set off for Scot-
land for the purpose of offering his services in manufacturing the patent instrument,
1818.] History of Dr. Brewster’s Kaleidoscope. 65
Professor Pictet’s opinion is stated in the following letter :
“« Sir,—Among your friends, I have not been one of the least
painfully affected hy the shameful invasion of your rights as an
inventor, which I have been a witness of lately in London. Not
only none of the allegations of the invaders of your patent,
grounded on a pretended similarity between your kaleidoscope
and Bradley’s instrument, or such as Wood’s or Harris’s theories
might have suggested, appear to me to have any real foundation;
but I can affirm that neither in any of the French, German, or
Italian authors, who, to my knowledge, have treated of optics,
nor in Professor Charles’s justly celebrated and most complete
collection of optical instruments at Paris, have I read or seen any
thing resembling your ingenious apparatus, which, from its
numberless apphsations, and the pleasure it affords, and will
continue to afford, to millions of beholders of its matchless
effects, may be ranked among the most happy inventions science
ever presented to the lovers of rationalenjoyment..
“ M.A. Picret,
Professor of Nat. Phil. in the
“* To Dr, Brewster.” Academy of Geneva.”
The propositions in Harris’s Optics relate, like Professor
Wood’s, merely to the multiplication and circular arrangement
of the apertures or sectors formed by the inclined mirrors, and
to the progress of a ray of light reflected between two inclined
or parallel mirrors ; and no allusion whatever is made, in the
propositions themselves, to any instrument. In the proposition
respecting the multiplication of the sectors, the eye of the
observer is never once mentioned, and the proposition is true if
the eye has an infinite number of positions ; whereas, in the
kaleidoscope, the eye can only have one position, In the other
proposition (Prop. XVII.) respecting the progress of the rays,
the eye and the object are actually stated to be placed between
the refiectors ; and even if the eye had been placed without the
reflectors, as in the kaleidoscope, the position assigned it, at a
reat distance from the angular point, is a demonstration that
arris was entirely ignorant of the positions of symmetry either
for the object or the eye, and could not have combined two
reflectors so as to form a kaleidoscope for producing beautiful or
Symmetrical forms. The only practical part of Harris’s proposi-
tions is the fifth and sixth scholia to Prop. XVII. In the fifth
scholium he proposes a sort of catoptric box or cistula, known
long before his time, composed of four mirrors, arranged in a
most unscientific manner, and containing opaque objects between
the speculums, ‘“ Whatever they are,” says he, when speaking
of the objects, “the upright figures between the speculums
should be slender, and not too many in number, otherwise they
will too much obstruct the reflecied rays from coming to the eye.”
This shows, in a most decisive manner, that Harris knew nothing
Vou. XII. N° I. E
66 Eistory of Dr. Brewster’s Kaleidoscope. [JuLy,
of the kaleidoscope, and that he has not’ even improved the
common catoptric cistula, which had been known long before.
The principle of inversion, and the positions of symmetry, were
entirely unknown to him. In the sixth scholium, he speaks of
rooms lined with looking-glasses, and of luminous amphitheatres,
which, as the Editor of the Literary Journal observes, have been
described and figured by all the old writers on optics.*
The persons who have pretended to compare Dr. Brewster’s
kaleidoscope with the combinations of plain mirrors described by
preceding authors, have not only been utterly unacquainted with
the principles of optics, but have not been at the trouble either
of understanding the principles on which the patent kaleido-
scope is constructed, or of examining the construction of the
instrument itself. Because it contains two plain mirrors, they
infer that it must be the same as every other instrument that
contains two plain mirrors, and hence the same persons would,
by a similar process of reasoning, have concluded that a tele-
scope is a microscope, or that a pair of spectacles with a double
lens is the same as a telescope or a microscope, because all these
instruments contain two lenses. An astronomical telescope |
differs from a compound microscope only in having the lenses
placed at different distances. The progress of the rays is exactly
the same in both these instruments, and the effect in both is
produced by the enlargement of the angle subtended by the
object. Yet surely there is no person so senseless as to deny
that he who first combined two lenses in such a manner as to
discover the mountains of the moon, the satellites of Jupiter and
Saturn, and all the wonders of the system of the universe, was
the author of an original invention. He who produces effects
which were never produced before, even by means which have
been long known, is unquestionably an original inventor ; and
upon this principle alone can the telescope be considered as an
invention different from the microscope. In the case of the
kaleidoscope, the originality of the invention is far more striking.
Every person admits that effects are produced by Dr. Brewster’s
instrament, of which no conception could have been previously
formed.
All those who saw it, acknowledged that they had never seen
any thmg resembling it before; and those very persons who had
been possessors of Bradley’s instrument, who had read Harris’s
‘Optics, and who had used other combinations of plain mirrors,
never Hs es for a moment, that the pleasure which they derived
from the kaleidoscope had any relation to the effects described
by these authors.
No proof of the originality of the kaleidoscope could be
stronger than the sensation which it created in London and
* The reader is requested to examine carefully the propositions in Harris’s
Optics, which he will find reprinted in the Literary Journal, No. 10. He will
then be convinced that Harris placed both the eye and the object between the
mirrors, an arrangement which was known 100 years before his time.
1818.] Proceedings of Philosophical Societies. 67
Paris. In the memory of man, no invention, and no work,
whether addressed to the imagination or to the understanding,
ever produced such an effect. A universal mania for the instru.
ment seized all classes, from the lowest to the highest, from the
most ignorant to the most learned, and every person not only
felt, but expressed the feeling, that a new pleasure had been
added to their existence. ;
If such an instrument had ever been known before, a similar
sensation must have been excited, and it would not have been
left to the ingenuity of the half learned and the half honest to
search for the skeleton of the invention among the rubbish of
the 16th and 17th centuries.
SS CG
ARTICLE X.
Proceedings of Philosophical Societies.
ROYAL SOCIETY.
May 28.—A paper, by John Pond, Esq. Astronomer Royal,
was read, on the parallax of the fixed ‘stars in right ascension.
The author stated that this paper was an appendix to a former
one on the same subject. He divides the results of his observa-
tions upon certain stars into two parts, according as they were
made what he calls incidentally or according what is termed the
law of parallax ; and as no greater difference was observable in
the latter than in the former case, it is concluded that the paral-
lax is not so considerable as to be sensible,
A paper, by Mr. Donovan, was also read, on the oxides and
salts of mercury.
Mr. Donovan commences by giving a view of what had been
done by preceding chemists ‘on this subject, and afterwards
relates his own experiments. He thinks the protoxide of mercury
consists of 100 parts of mercury to 4:12 parts of oxygen; while *
the peroxide consists of 100 parts of mercury to 7-82 parts of
oxygen. These he supposes to be the only oxides of mercury,
the one corresponding to the black, the other to the red.
June 4.—A paper, by Sir Ev. Home, Bart. V.P.R.S. was
read, containing an account of the teeth of the delphinus gange-
ticus ; also a paper, by T. Smith, Esq. on the structure of the
poisonous fangs of serpents.
A paper was also read, by A. B. Granville, M.D. on sulphur-
eted azote, a substance which he supposes to be the produce of
@ peculiar process of animal decomposition, which takes place in
the living body. It existed as a component part of a gas which
was found in the abdomen, and was mixed with a portion of
carbonic acid. It was Supposed to be composed of 89+ parts
of azote and ‘102 of sulphur.
A paper was also read containing an account of some eXxperi-
E 2
68 Proceedings of Philosophical Societies. [Jury,
ments made to ascertain the effects of voltaic electricity upon
vegetable life, by J. Williams, Esq.
June 11.—A paper, by Dr. Prout, was read, on a new acid
principle prepared from lithic or uric acid. The beautiful purple
substance produced by the action of nitrie acid and heat upon
lithic acid has been long known to chemists. This substance
Dr. P. has shown to be a compound of a peculiar acid with
ammonia.
_ This acid principle, which may be likewise formed from the
lithic acid by chlorine and iodine, possesses the remarkable
property of forming beautiful purple compounds with the alkalies
and alkaline earths ; hence the name of purpuric acid has been
adopted by Dr. P. which was suggested by Dr. Wollaston.
urpuric acid may be separated from the purpuret of ammonia,
before mentioned, by the sulphuric or muriatic acids. It usually
exists in the form of a light yellow or cream-coloured powder.
It is exceedingly insoluble in water, and consequently possesses
no taste, nor affects litmus paper, though it readily decomposes
the alkaline carbonates by the assistance of heat. It is soluble
in the strong mineral acids and in alkaline solutions, but not in
dilute acids in general. In alcohol, it is insoluble. When
exposed to the air, it assumes a purple colour, probably by
attracting ammonia. Submitted to heat, itis decomposed, and
yields carbonate of ammonia, prussic acid, and a little fluid of
an oily appearance. Burned with the oxide of copper, it was
found to consist of
Carbomo wails 5 HOUT
‘Avote Gowers eth Se) SBRSi
The alkaline purpurates, as before observed, all form solutions
of a beautiful purple colour. They are capable of crystallizing,
and their crystals possess some remarkable properties. The
-purpurate of ammonia crystallizes in quadrangular prisms, which,
when viewed by transmitted light, appear of a deep garnet red ;
but by reflected light, two ofthe opposite surfaces appear ofa beau-
tiful green, while the other two opposite surfaces appear of the
natural colour. This curious property seems to be possessed by
the other alkaline purpurates. The metallic purpurates are, in
general, remarkable for their solubility and the beauty of their
colours. The purpurate of zinc is of a beautiful gold yellow, the
purpurate of tin of a pearly white, that of the other purpurates
are more or less of a red colour.
' Dr. P. thinks it probable that this acid forms the basis of
many animal and vegetable colours. The pink colour of the
sediment in the urine of fever seems to be owing to the purpu-
rate of ammonia. Dr. P. also thinks that some of its salts might
be used as paints, and also for dyeing, as they appear to possess
strong affinities, especially for animal substances.
——
1818.] Geological Society. 69
A paper, by Sir W. Herschell, was also read, entitled astro-
nomical observations and experiments selected for the purpose
of ascertaining the relative distance of clusters of stars ; and of
investigating how far the power of our telescopes may be
expected to reach into space when directed to ambiguous celes-
tial objects.
GEOLOGICAL SOCIETY.
March 6.—A paper was read, entitled ‘‘ Observations on the
Valleys and Watercourses of Shropshire, and of Parts of the
adjacent Counties,” by Arthur Aikin, Esq.
From the heights of parts of the line of the Ellesmere canal,
and from other data, Mr. A. computes the summit level of the
tract which separates the valley of the Dee from that of the
Severn, to be about 295 feet above the Dee at Chester; and the
height of the Severn at Shrewsbury to be about 155 feet above
the Dee at Chester.
The descent of the Severn from Llanidloes to the sea appears
to be at the rate of 11 feet per mile for the first 20 miles, not
navigable ; then three feet eight inches per mile for 26 miles ;
one foot eight inches per mile for 21 miles, and from Worcester
to Gloucester, about 30 miles, only four inches per mile.
From a variety of observations on the course of the Severn,
Mr. A. concludes that the navigation of a river is very precarious,
and lable to long and frequent interruptions, even in a rainy
climate, when the descent of the stream exceeds three feet per
mile, and that the highest floods run off in a few hours, even
when the descent amounts to two feet six inches in the same
space.
The descent of the Dee from Llandysilio to Pont y cysyllte, a
distance of six miles, is at the rate of 22 feet per mile; and
thence to Chester, amounts to about five feet one inch per mile.
The heights of water-sheds, or sources of rivers, being import-
ant points in physical geography, Mr. Aikin recommends the
subject to the notice of such members of the Society as may be
enabled to supply information concerning it. ©
April 3.—A paper was read, from Dr. Brewster, on the form
of the integrant molecule of carbonate of lime.
Dr. B. has discovered that the strie passing through the long
diagonals of two opposite planes of the primitive rhomboid of
carbonate of lime are occasioned by their traversing veins com-
posed of rhomboids of different thicknesses, having their faces
placed transversely to those of the rhomboid which they traverse,
and adhering firmly to the two surfaces between which they are
interposed. Dr. B. rests the proof of this fact on the action
which the surface of the crystal exerts on aray of light. He
concludes that the integrant molecule is not a trihedral prism,
as Count Bournon supposed, since the transverse cleavage of
the primitive rhomboid exists only in those specimens which are
crossed by intersecting veins.
70 _ Proceedings of Philosophical Societies. [Juny,
A paper was read from A. S. Lillingston, Esq. on granite veins
and whin dykes, in which he explains these appearances on the
supposition that the beds containing the veins were deposited
upon the mass of which the vein is a portion, while that mass
was in a fluid state; and that the deposited beds were the first
to become hard, in consequence of which they contracted, thus
occasioning fissures which were subsequently filled by the sub-
jacent fluid mass.
The author also supposes the red marl stratum to have been
produced from the destruction of beds of whin stone, fragments
of which abound init, as may be observed in Devonshire, North-
umberland, and other places.
A letter was read, from the Rev. W. Gilpin, on certain fossil
bones found near Margate. These bones, in the state of frag-
ments, occur in the hard, white, calcareous clay which overlies
the extremity of the chalk cliff extending along the coast to the
westward of Margate. The bones lie at least 10 or 12 feet
below the surface, and are surrounded by a dark, friable sub-
‘stance, similar to decayed animal matter.
April 17.—A second paper was read, from George Cumber-
land, Esq. on some new encrinital and pentacrinital bodies
found in the nighbourhood of Bristol. It affords much interest-
ing and curious information concerning the class of bodies of
which it treats, but which cannot conveniently be detached
from the illustrative series of drawings by which it is accom-
panied.
May 1.—A paper was read, from George Cumberland, Esq.
consisting of a descriptive catalogue of specimens of the Bristol
limestone beds, from their transition from the sandstone to their
termination, at a place called Cook’s Folly, nearly the whole of
which Mr. Cumberland has measured. The series consists of
above 300 beds, from one inch to 30 feet in thickness.
A paper was read, from Francis Lunn, Esq. on the strata of
the northern division of Cambridgeshire.
Mr. Lunn observes that the ferruginous sand is the lowest
stratum found in Cambridgeshire ; on this rests the blue marl,
having in many places the line of their junction very well defined:
the sand contiguous to the clay is generally cemented by a large
portion of oxide of iron into a hard, rocky substance. The sand
contains fossil wood ; the clay contains carbonate and sulphate
of barytes. The temperature of the water in all the wells sunk
through the clay, is about 47° Fahrenheit, and is nearly invari-
able throughout the year. :
May 15.--The following notices were communicated by
M. Leman, M.G.S. through Mr. Heuland, For. Sec.
On Mica.—M. Biot has lately divided this mineral into two
species. When submitted to the action of polarized light, the
coloured rigs which are produced are traversed in the first
species by two axes in the form of a black cross; and in the
second species by a second axis or black band, passing through
1818.] Linnean Society. 71
their centre. The surfaces of the first species. are smooth and
brilliant, while those of the second are dull and finely furrowed.
-M. Vauquelin has found a difference in the chemical constituents
of the two species. Crystallography appears to admit as the
primitive form of mica either a right or an oblique rhombic prism.
Is it not probable that these may be the respective primitive
forms of the two species ?
On Wallerite, or Linzinite.—-Dr. Dufour, of St. Sever, Dept.
des Landes, has lately discovered near that place, in a bed of
clay, a substance externally resembling lithomarga. It appears,
however, from an analysis of it by M. Laugier, to contain
LER ah ooanacotere aie eterahebeeeton art ete 32
Aline: Se, ota ik eretveec iota 37
Weatera ein Le Sie cee Stee ele 27
_ Sulphate of lime. ....... eh heRS
99
It may, therefore, be considered as a siliceous hydrate of
alumine.
LINNEAN SOCIETY.
May 5.—A continuation of the Rev. Mr. Kirby’s century of
new insects was read.
May 25.—The following is the list of officers for the ensuing
_year.
President.—Sir James Edward Smith, M.D.
Vice Presidents.—Samuel Lord Bishop of Carlisle ; Aylmer
‘Bourke Lambert, Esq.; William George Maton, M.D.; Edward
Lord Stanley.
Of the Council, in Place of five Members who go out.—John
Duke of Bedford; Mr. Andrew Forster; Thomas Andrew
Knight, Esq.; Thomas Reynolds, Esq.; Sir George Thomas
Staunton, Bart. ;
Treasurer.—Edward Forster, Esq.
Secretary.—Alexander M‘Leay, Esq.
Under Secretary.—Mr. Richard Taylor.
June 2.—A paper was read, by Capt. Carmichael, on the genus
pandanus.
June 16.—A letter was read, addressed to the Rev. Mr. Kirby
by the Rev. Revett Sheppard, on the position of the toes in
‘certain genera of birds.
The woodpecker tribe have four toes on each foot, two before
and two behind, which arrangement, according to Ray and all
subsequent naturalists, is for the purpose of enabling them to
climb with facility. According to Mr. Sheppard, there are six
genera of birds pedibus scansoriis, viz. psittacus, cuculus, picus,
rhamphastus, trogon, and bucco.
The common cuckoo, which is one of these, though furnished
with two toes before and two behind, is never known to climb at
all; while the nuthatch (sitta europea) and tree creeper (certhia
72 Scientific Intelligence. (Jury,
familiaris) have their toes placed in the usual manner, viz. three
before and one behind, and yet run up and down trees with great
facility. From these and similar cases Mr. 8. conSiders the pes
scansorius as intended not for climbing, but for secure prehension;
and hence it is found in the woodpecker and others which, hav-
ing to procure their food by penetrating the wood with their
strong bills, require a firm footing, which is effected by the
arrangement of their toes as already stated. ;
ee
ArTicLe XI.
SCIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS
CONNECTED WITH SCIENCE.
I. Attempts to penetrate into the Interior of Africa,
In the Journal of Science and the Arts, v. 146, we have the
following account, which we believe is the only authentic docu-
ment, that has yet been published, of the unfortunate termination
of the expedition under Major Peddie,
“ A letter from Sierra Leone mentions the return to that place
of the scientific expedition for exploring the interior of Africa.
They were completely unsuccessful, having advanced only about
150 miles into the interior from Rio Nunez. Their progress was
then stopped by ‘a chief of the country; and after unavail-
ing endeavours, for the space of four months, to obtain liberty
to proceed, they abandoned the enterprize and returned, Nearly
all the animals perished. Several officers died, and but one
private, besides one drowned, of about 200. Captain Campbell
died two days after their return to Rio Nunez, and was buried
in the same spot where Major Peddie and one of his officers
were buried on their advance.”
Our expectation of penetrating into the interior of Africa has
received a stil! more crue! disappoitment in the death of that
intrepid and adventurous traveller Burckhardt, which took place
on October 15, last, at Cairo. He had resided nearly eight
years in Egypt and Syria, and had diligently occupied himself
in exploring these countries, and in making himself thoroughly
acquainted with the language, manners, and religious ceremonies
of the Arabs, He had so far attained this object as to have
adopted their dress and costume, and under the denomination of
Sheich Ibrahim, had effectually concealed his European origin,
‘Having completed all his preliminary arrangements, he was
anxiously waiting for the arrival of a caravan from Mourzouk,
which he proposed to accompany on its return, when he was
seized with an attack of dysentery, which in ten days terminated
fatally.
This succession of disappointments has not, however, repressed
the ardour of adventure, and we learn that Mr. Ritchie, late
private secretary to Sir Charles Stuart, has undertaken to reach
1818.] Scientific Intelligence. 73
the Niger and Tombuctoo by a new route, which seems indeed
to hold out peculiar advantages. The present Bashaw of Tripoli
has intimated his readiness to co-operate with the British
government in the promotion of their plans ; Fezzan is a depend-
ency of Tripoli, and is at this time governed by a Bey, who is
the son of the Bashaw; and it appears that there is a constant
communication between Fezzan and Kashna, Bournou, and even
Tombuctoo itself. It seems that the French are likewise turning
their attention to the same object, and that the traveller Bahdia,
who is so well known under his assumed name of Ali Bey, is
now entering upon an expedition, which is stated to be nearly
the same with that which had been projected by Burckhardt.
If. On Pargasite.
(To the Editors of the Annals of Philosophy.)
GENTLEMEN, -
The new mineral, of which you have given a short notice in the
fast number of the Annals under the name of pargasite, has been
known in this country three or four years, and was described by
the Abbé Haity in vol.i. of the “ Memoires du Museum d’His-
toire Naturelle,” published in 1815; he found the crystalline form
of many of the grains, and the cleavage, similar to those of horn-
blende ; of which mineral he considered it a variety. He says he
observed in some of the grains traces of a dihedral summit, and
these traces have probably led the author of the description you
have copied to regard the form of the substance as an octohe-
dron; a form which would obviously result from a very short
prism with the dihedral termination. The relative proportions
of the component parts of hornblende differ considerably in the
different analyses which have beem published. But the presence
of fluoric acid does not appear to have been noticed before.
I am, Gentlemen, yours, &c. FJ.
N.B. Has not Capt. Hall mistaken some of the mollusce for
polypes in the description you quote of the coral reefs, observed
by him near the island of Loo-Choo?
Il. On Mr. Tritton’s distilling Apparatus.
(To the Editors of the Annals of Philosophy.)
GENTLEMEN,
You have inserted in the last number of the Annals an account
ofthe apparatus contrived by Mr. Tritton for distilling in vacuo ;
the attempt, although not new, is specious; and when the
method is recommended by so respectable a philosopher as Mr.
Allen, it is extremely probable ¢that it will, to a certain extent,
meet with the patronage of the public. I had prepared some
remarks to show that the employment of the apparatus in ques-
tion must necessarily end in disappointment ; 1 shall, however,
content myself with merely sending you for insertion im the
Annals the following extract from vol. i. p. 190, of Dr. Black’s
74 Scientific Intelligence. [Juny,
Lectures ; in which it will appear that this illustrious philosopher —
and his eminent friend Mr. Watt, are theoretically and experi-
mentally inimical to distilling in vacuo.
Your constant reader, Po.
Mr. Watt “ finds that water distils perfectly well, when of the
temperature 70°, and that, in this state, the latent heat of the
steam approaches to 1,300, and certainly exceeds 1,200. The
unexpected result of these experiments, is, that there is no
advantage to be expected in the manufacture of ardent spirits
by distilling in vacuo; for we find that the latent heat of the
steam is at least as much increased as the sensible heat is dimi-
nished. This will undoubtedly be attended with an increased
expenditure of fuel ; for the increase of 100 degrees of sensible
heat occasions an increase of fuel only while we are raising the
temperature of the still to the ordinary heat of boiling water, in
the beginning of the distillation. If the furnace be judiciously
constructed, and due precautions taken to prevent dissipation, it
requires very little fuel to maintain this temperature. But 100
degrees of latent heat is an expense that is continual, and
which no contrivance whatever can prevent.”
On the subject of Mr. Tritton’s method of distilling in vacuo,
the Editors beg to remark, that this gentleman does not, in his
letter, state the saving of fuel as an advantage likely to arise
from his process, but merely the improved quality of the fluid,
as being free from the unpleasant flavour which is apt to attach
to spirits distilled at a high temperature. The experiments on
the oils contained in different species of corn, mentioned at
p- 35 of this number, may probably throw some light upon the
point in question.
IV. Newly discovered Membrane in the Eye.
Dr. Jacob, Demonstrator of Anatomy in the University of
Dublin, has discovered, and demonstrated in his lectures on the
diseases of the eye, this spring, a membrane covering the exter-
nal surface of the retina, in man and other animals. Its extreme
delicacy accounts for its not having been hitherto noticed. He
arrived at the discovery by means of a new method of displaying
and examining this and other delicate parts. He argues from
analogy the necessity of the existence of such a membrane, as
parts so different in structure and functions as the retina and
choroid coat must otherwise be in contact, in contradiction to
the provisions of the animal economy in general. A detailed
account of the discovery, with the method of displaying the
membrane, is in preparation, and will shortly be laid before the
public.
V. Plate presented to Dr. Paris.
-On Tuesday the 16th instant, a deputation of noblemen and
gentlemen, of the county of Cornwall, waited upon Dr. Paris, at
1818.] Scientific Intelligence. 75
his house in Dover-street, with a magnificent present of plate
for his acceptance. The inscription, which is engraved on a
massy silver waiter, records the services for which it was given.
“ To John Ayrton Paris, M.D. F.L.S. Fellow of the Royal Col-
lege of Physicians of London, this plate is inscribed by the
noblemen, representatives in Parliament, and gentlemen of the
county of Cormwall, in testimony of their grateful sense of his
services, in originating the plan, and promoting the institution of
the Royal Geological Society of the county, which has rendered
their home the school of science, and their native riches increas-
ing sources of prosperity.”
VI. On the Spiral Oar. By James Boaz,. Esq.
(To Dr. Thomson.)
SIR, Glasgow, June 8, 1818.
In your Annals of Philosophy for this month, I see a paper
signed by Mr. T. L. Dick, stating that Mr. Scott, of Ormiston,
had shown him a drawing of a spiral oar for propelling a vessel.
As I consider this kind of oar may be brought to do much good in
that way, | beg leave to state that the same occurred to me on
August 12, 1804, which was the day after I had been foiled in
an experiment by another method for propelling a small boat (on
the Hugginfield Loch) used at building the wooden bridge over
the Clyde here. I soon after made a model of a boat on a small
scale, with two strong clock springs in one barrel, to drive a train
of wheels, which wrought one of these spiral oars inside of a
double keel at the bottom of the vessel, having gratings to pre-
vent weeds from getting foul of the oar. I tried various sorts of
spiral, some with the thread very close, others more sparse, and
a few with two, three, and even four threads. I was best pleased
with that having a double thread and moderate angle, as the
motion of the model in the water at an experiment, Nov. 2, 1804,
was at the rate of from four and a half to five miles per hour.
This, if necessary, 1 can produce credible witnesses to testify.
Whether the idea was new on August 12, 1804, I know not—
it was so to me.
A spiral has since, under my direction, been successfully
applied to force hot air into a cold ae where there was
_ power to spare for driving it; and I have often thought that
the principle, if properly executed on a large scale, might in some
cases be used for ventilating coal and other mines so as to free
them of dangerous gases. Your obedient servant,
James Boaz.
VII. A new Metal.
We are informed that Prof. Stromeyer, in examining the subli-
mate which concretes in the chimnies of the zinc furnaces of
Saxony (and which has long been known to chemists by the name
of Cadmia fornacum), has discovered a new metal, to which he
has given the name of Cadmium. Of this we hope to be able to
give a further account in our next number.
=~
May 4. Solar eclipse Bia
Astronomical Observations.
Beginning 17) 53/
End. ....
ARTICLE XII.
Astronomical, Magnetical, and Meteorological Observations.
By Col. Beaufoy, F.R.S.
Bushey Heath, near Stanmore.
Latitude 51° 37/ 42” North. Longitude west in time 1! 20°7’.
May 19. Immersion of Jupiter’s second
satellite
wees
19 41
Hd 09/
13 10
Bal
17
76 Colonel Beaufoy’s Astronomical, Magnetical, [Juty,
: Mean Time at Bushey.
31” Mean Time at Bushey.
51°T Mean Time at Greenwich.
Magnetical Observations, 1818. — Variation West.
Month.
‘ Hour.
May 1] 8h 40’
2) 8 15
3) 8 40
4) 8 30
5| 8 25
6; 8 30
%| 8 35
8) 8 40
9| S$ '35
10; 8 35
1h} 8 25
32 8 30
13|.8 40
4/| 8 20
15; 8 40
16] 8 25
17} 8 40
18; 8 20
19} 8 40
20| 8 25
21; 8 30
22| 8 25
23; 8 30
24; & 30
25} 8 30
26) 8 30
271 8 25
28! 8 25
29; 8 30
30} 8 30
31) 8 25
Mean for
Month. § SiiRd
Morning Observ.
Variation.
24°
36’
32
Noon Qbsery.
Hour.
a Sp ees OS ed Pee ee ara el ee
24
Variation.
24° 45!
24
24
24
24
24
24
24
24
AA
45
AG
A4
45
AS
50
A5
A5
45
46
AT
42
AA
44
46
48
46
46
A5
Ad
43
44
44
47
46
45
33"
49
24 45 49
Evening Observ.
Hour.
Pre ses eee ee eee | Oa oq caietey capeajeaeeedel | pe SETEP || |
qh 15/
15
15
10
Variation.
24° 38’
24
24
24
36
383
37
35
38
38
36
37
39
Q5
46
51
30
—
16
14
40
50
50
34
54
53
13
28
13
36
26
44
10
46
58
00
54
03
24
24 38 35
Rain, by the pluviameter, between noon on May 1, and noon
the Ist of June, 2455 inches. Evaporation, during the same
period, 3°77 inches.
1818.] and Meteorological Observations. 77
,
Meteorological Observations.
- Lh WG Ga Winans See
Month.
Time, | Barom. | Ther. | Hyg. | Wind. \Velocity.| Weatirer,| Six’s.
May Inches, Feet.
Morn ..,.| 29°300 53° | 54°) SW by S Shewery | 47°
hae --.| 29°363 57 44d |SW by W Showery| 58
Even ....| 29°445 50 AT SSW Clear 43
Morn.,..| 29-430 | 51 AT ESE Cloudy i
2 ae seis] SOc Ow le tae A3 Var, Showery | 53
Even .. = == _— — — 43
Morn,. 29-070 5t 83 ENE Sm. rain ‘
32 \Noon....| 29-053 60 57 ESE Fine 622
Even,...) — 7 cam = — 462
Morn....| 29-065 | 51 50 Ww Very fine ‘ 2
a Noon,. 29-083 62 40 Var. Fine 64
Even ....| 29-090 57 —_— Calm Fine 49
Mern....| 29-025 | 52 49 N Very fine i
54 |Noon....| 29 000 59 Al Var, Cloudy 62
Even ....| 28-970 55 AQ E Thunder 49
Morn....| 28:905 | 52 60 ENE {Cloudy ‘
G4 |Noon....| 28°390 59 49 SSW Rain, thund.| 61%
Even....| 28-885 52 54 s Fine
Morn....| 28-900 | 51 | 60 sw Cloudy ‘ 48
74 |Noon....| — — pes pass ees 59
.|Even.. ses = = = = ;
Morn....| 29113 | 53 | 51 SSE Fine ‘ 46
Noon....| 29°113 60 38 SSE |Fine 634
Even ....| 29 005 — 50 E Rain a
Morn... 29123 | 53 | 51 | SW byS Fine ‘ 453
Noon, ...| 29-158 58 46 SSW Showery}] 6Q
Even ..,.| 29°220 52 50 SSW Fine
‘Mora....| 29-418 | 51 | 41 SSW Very fine ‘ 44
104 Noon... .| 29-418 | 57 42 Var. Showery| 60
Even .,,.| 29-400 | 52 48 S by W Fine ie
Morn.,..| 29°285 | 54 | 49 s Fine ‘ as
114 (Noon. ...| 29-240 | 62 | 39 SSW Fine 63
Even ..,.}| 29-200 55 45 Sby W Cloudy
Morn... | 29-200 | 53 | 50 Ww Fine t 492
124 'Noon,...| 29°213 | 58 | 39 Ww Cloudy | 60
Even ....| 29°235 55 Al W byS Fine ‘ Ah
Morn....| 29-000 AQ 65 ESE Rain ~
is} Noon,,..| 28°930 | 57 48 |SW byS Showery| 58
jEven.. spec CoS 50 50 |SW by S fine 43
|Morn,...| 28°930 | 51 54 Ss Showery
149 \Ncon.... = == = = — —
|Even....| 29°054 | 49 56 SE by S "ine 458
Morn,....| 29:090 | 53 51 Var. Cloudy : =
154 \Noon....| 29070 | 53 | 42 NW Cloudy | 61
Even ....| 29°085 53 47 ENE Fine 43
|Morn,...} 29°122 5] 56 Wby N Cloudy ‘
165 'Noon....| 29-137 | 57 | 44 | WNW Showery| 59%
Even ...| 29°190 53 51 WbyN Cloudy 50
Morn, 29°243 58 74 NW Rain ‘
ir} Noon,...| 29271 | 54 | 70 NE Rain 55
Even....| 29°330 | 53 68 NE Cloudy 4b
{\Morn....| 29-455 | 52 | 54 | NNW Very fine ‘ :
18) |Noon.... -- — -- oo = 66
Even....] 29°510 | 53 AT NNE Fine
(nape
78 Col. Beaufoy’s Meteorological Observations. [Jury,
Meteorological Observations continued.
Month. | Time. | Barom.| Ther.| Hyg.| Wind. |Velocity.| Weather.|Six’s.
May Inches, Feet. ’
~|Morn,.,.| 29°550 499 | 62° | NE by N Cloudy Abe
192 |Noon..,.| 29°365 | 55 | 53 | NEby N Cloudy | 56
Even ....| 29°570 AQ 60 | NE byN Cloudy Al
Morn,...| 29-615 49 49 NE by N Very fine ‘
20} Noon,...| 29:623 60 36 Eby N Very fine] 62%
Even....) — os — ae shez
/|Morn... | 29°733 | 49 50 ENE Cloudy ‘
a} Noon....| 29°750 56 38 | NEby E Very fine} 58
Even...) 29°735 49 Al EbyN Clear 38
.|Morn....| 29-773 48 48 ENE Fine ‘
cat Noon....| 29:790 | 57 38 EbyN Very fine} 59
Even....| 29°810 | 52 Ad | E Clear NW
Morn.....| 29:873 | 50 | 48 | ENE Fine é
2345 |Noon....| 29°862 57 40 ENE 5'894 |Very fine] 60
Even ...) — — — = a an
§ Morn,...| 29-900 52 54 Eby N Fine ‘
_ 245 |Noon,...| 29-900 61 37 E ; 11163 |Clear 624
it Even ....| 29:S90 55 39 E Clear 46
Morn,...| 29°895 | 51 5T ENE . Cloudy é
254 |Noon....| 29°865 60 44 ENE 7255 |Fine 63
Even ....| 29°835 55 Ad Eby N Clear ~ A
| |Morn,...| 29°837 55 51 ENE Very fine :
20) Noon,...} 29°820 66 33 E 7033 |Clear 663
Even... .} 29°823 57 35 _E Clear AA
Morn,...| 29°883 | 52 | 51 NE Very fine ‘ 2
274 |Noon,...}| 29°867 63 42 NE 5103 |Very fine} 64
Even....| 29°827 62 Al NNE Clear 4g
Morn,...| 29°772 53 A5 “NNE Clear ‘ é
2845 |Noon....} 29-760 | 65 32 NNE — |Very fine} 66
Even...) 29°720 50 42 NE Fine AA
Morn,....| 29°673 | 51 42 | NEbyN Cloudy ‘
294 |Noon....| 29°673 57 35 N by E — Fine 60
Even ....| 29°670 | 52 37 N Fine 43
Morn... .| 29°685 48 42 NNE Cloudy ‘
304 |Noon....| 29'652 | 57 39 NNE 3604 |Fine | 59%
Even....| 29°610 | 48 43 E Fine 45
Morn....| 29°542 | 55 | 47 |NW by W Very fine ‘ 4
31) |Noon....} 29°530 68 31 N see Fine | Tl
Even ....| 29°530 | 56 50 Var, Showery
———
1818.]} Mr. Howard’s ‘Meteorological Table. 79
ArTicLe XIII.
METEOROLOGICAL TABLE.
1818, |Wind.
4th Mon.
April 28S W
20IN E
30} Var.
5th Mon.
May 18 W
2) Var.
3\I8 W
4iN W
SIN E
The observations in each line of the table apply
BAROMETER,
29°98 |29°80/29°890
29-98 |29°7 5|29°865
29°88 |29°75)29°815
29°88 /29°70|29°7 90
29°85 /29°45|20-650
29°4,8'29°36|29°4.20
29°4.8/29'40|29°4.40
29'26|29°22|29-240
29°51/29:26/29'385
29°51|29°40/29:4.55
29°84|29°51|20°675
29°84!29°67|29'7 55
29°67 |29' 57 |29°620
29°03|29'45/29°540
29:45'29°30!29:375
29:47 |29°30/29:385
29°52'29°47|29°495
29°65'29°52/20°585
29;87 |29°05]29-7 60
30°00/29°87|29:935
30°05 30:00/30-025
30°20 30°05/30°125
30°23'30°20)/30:215
30°32 30°23|30°275
30°35/30°32/30°335
30°3.5,30'25/30°300
30°26 30'25/30°255
30°33 30°23/30:280
29°4.0|29'26/29°330) -
30°35 29'22/29°766
THERMOMETER,
Max.| Min. ; Med. |Max.| Min.
Ce ee ee eee
Hygr. at |
Med. | 9 a.m. |Rain.
41°5 53
530 50
50°5 70 51
47°5 56 5
580 52 39
54:5 75 3
545 58
56°5 62 183i@
550 | 72 | 31
525 |. 63 “| —
54°5 1°46
52'5 2
50-5.) Oar) —
580 | 43 2
53:0 | 44 5
51:0] - 59 | 101)
48:5 | 57
52'0 46 | —
565 | 45 5
525 | 75
58:0
47°5
55:0 fe)
47°5
51°5
49-0
53°5
52:5
55*5 C
52°84! 57! 3-28)
to a period of twenty-four
hours, beginning at 9 A.M. onthe day indicated in the first column, A dash
denotes, that the result is included in the next following observation.
80 Mr. Howard’s Meteorological Journal. [Jury, 1818.
REMARKS,
Fourth Month.—28. Much dew: at nine a, m. a brisk wind carrying Cumulz,
above which appeared beds of Cirrus and Cirrecumulus, moving from SE; a fine
day ensued, with Cumulostratus. 29. Fine. 30, Overcast early, with the wind
NE; after which wet till evening.
Fifth Month.—l. A fine day, save a shower or two. 2. Large Cumuli rose,
which in the E especially mingled and inosculated with Cirrostratus above; I sus-
pecied thunder in that direction; at sunset, Cirri from N to $8, above Cirrostraté
ranging E and W: rain by night. 3. Drizzling, a. m.: fine, with Cumulus, and
Cirrus at mid-day: in the evening, heavy showers appeared to the Nand NE, with
much Cirrostratus overhead. 4. Very fine, with Cumuli, and large, plumose Cirrt
stretching Eand W ; the clouds, though heavy, dispersed at sunset. 5, Sunshine
at six a. m. with a few Cirri, &c.: before seven, a sudden mist came on from the
E and NE, which obscured the view of the Solar Eclipse during the middle half
hour of the time; the dew lay on the grass till noon, in the sunshine, and large
Cumuli formed, inosculating with the clouds above; at two p. m. some heavy
showers fel], but so local, that the road, half a mile off to the $, remained dusty:
in the evening, Nimbi appeared in thunder-groups to the SE and S, and, finally,
more extensive rain came on, withthe wind SE, 6, Rain, a.m., and at night.
Y
' RESULTS.
Winds Variable.
Barometer: Greatest height ,.............+.++++ 30°35 inches 3
Bicasth ck ce dacsetese oe Diels eels gates, ea oor CHEN «
Mean of the period ........ eosse- 29°766 inches.
Thermometer: Greatest height..............00000- 69° 2
Meantene.. osha ssta\op aces. veel aet ce sen OU™
Mean of the period .............. 52°84°
Hygrometer (mean of 18 days). . ........00ees000 DT
HEVAPOFAUON coaccsaee> cise wa tiesnt Gace cltaciay's) LaVOTEIDNeS.
RRA is ab clavate o Deiadacidt ens qpelevemae’s cedien niece CEN.
being, as usual of late, about double the average quantity.
Having left home on a journey on the morning of the 8th ult. I did not witness a
very uncommon fall of rain which took place in this neighbourhood, It com-
menced early in the evening of that day, and Jasted about 12 hours. Near an inch
and a half of water descended in the above space of time, which, taking the
shortest course from the higher ground to the hollows, filled the latter several feet
deep, and overflowed the roads, in several places not usually subject to this acci-
dent. Much inconvenience, and some loss ef property, ensued, the particulars of
which were detailed in the papers of the subsequent days, This heayy rain seems
to have been connected with a change in the general current, which, after a few
days further continuance of unsettled weather, became established from the north-
ward, the barometer assuming a high level, and the earth drying rapidly. It was,
indeed, a singular spectacle to behold the ground saturated with water, and every
spting running up to sv late a period in the season as the middle of the fifth mouth,
when our fields are commonly dry enough, in every situation, to admit of the soil
being pulverised by the harrows.
Torrennam, Sixth Month, 17, 1818, L. HOWARD.
I
a i i
‘a
ANNALS
OF
PHILOSOPHY.
AUGUST, 1818.
ArrIcLE I.
Biographical Sketch of Charles Augustin Coulomb.*
CHARLES AUGUSTIN COULOMB was bom at Angouléme,
on June 14, 1736, and was a member of a family that had been
distinguished for their public services in the town of Montpelier.
He came to Paris when very young, and soon manifested a
decided taste for mathematics ; but various circumstances hay-
ing prevented him from pursuing this branch of science, he
embraced the profession of a military engineer. In this capa-
city he spent about nine years in the West Indies ; he prosecuted
his employment with much ardour, and had the active superin-
tendence of many important public works; but from the
exertions which he made, together with the unhealthiness of the
climate, he experienced such unfavourable effects upon his con-
stitution, that it was necessary for him to return to frakbipe.
From this time Coulomb devoted himself almost entirely to
philosophical pursuits, directing his attention principally to the
mechanical sciences, or employing himself in elucidating them
by mathematical reasoning. Hé presented to the Academy,
from time to time, memoirs on various topics connected with
practical mechanics ; soon after his return from America, which
was in the year 1779, he divided with Van Swinden the prize
proposed for the best construction of the marier’s compass, and
two years afterwards had the prize awarded him for his paper on
the theory of simple machines. One of the most important
* The facts in this biographical sketch are principally taken from the eloge by
M. Cuvier, Mem, Inst. 6.
Vou. XII. N° Il. FE
82 Biographical Sketch of [Aveust,
topics which he discusses in this valuable memoir is that of
friction; he examined the opinions of those who had already
treated upon it ; he repeated and varied their experiments ; and
proceeding upon a larger scale, he obtained results which were
m many respects novel, and altogether very interesting. Some
of the most curious observations which he made were respecting
the relation between the length of time in which the effect of
friction reaches its maximum quantity, and the amount of the
weight or force employed. This relation he found to be of the
greatest importance in a practical point of view, and to influence
the results so materially, that unless it is taken into account, all
our calculations must be fundamentally erroneous. For example,
supposing that the force required to overcome the friction of one
surface upon another, as depending upon a certain pressure on
the surface, when the bodies were first placed in contact, was
100, in a few seconds it would be as 250 or 300, and ina few
days it would increase to 900 or 1000.*
n the researches to which he was led in his experiments on
the construction of the compass, he had occasion to pay parti-
cular attention to the effects of what he stiles torsion, or the
resistance which the suspending wire opposes to the action of
the needle, in obeying the magnetic attraction. This circum-
stance was the cause of Coulomb’s invention of what he deno-
minated his torsion balance, an instrument which he afterwards
employed very extensively for measuring minute forces, such as
those produced by extremely small quantities of electricity and
magnetism. An account of his experiments on this subject was
published in the memoirs of the Academy of Sciences for 1784,
under the title of theoretical and experimental researches on the
force of torsion, and the elasticity of metallic threads. The action
of the torsion balance essentially consists in the resistance which
an extremely fine thread opposes to our attempts to twist it, and
his object was to obtain an accurate measure of the force of this
resistance. The nature and construction of the instrument are
too well known to require any minute description ; it may be
stated, in general terms, as consisting of a metallic wire, which
is fixed at its upper end and is suspended in a vertical direction,
while to its lower end is attached a cylinder connected with a
horizontal index ; by causing the arms of the cylinder to revolve
upon the point of suspension, the wire to which it is attached
is twisted; and when we cease to twist it, its elasticity causes it
to assume its natural position. The index in this case will pass
through a certain space which is measured by a graduated scale.
Coulomb’s experiments led him to conclude that the force with
* Mem, Scay. Etrang. x. 163. The prize was awarded in 1781, and the paper
printed in 1784.
+ A figure of the torsion balance may be found in the Supplement to the Enc.
Brit. Pl. 27, figures 1, 2, 3, 4,5, alsoin Dr. Brewster’s Encyc. Art, Electricity,
Pj, 244, fig. 7, 8, 9, 10. ;
1818.] Charles Augustin Coulomb. 83
which the wire endeavours to regain its natural position is in the
direct ratio of the distance to which it has been removed from
it; and hence, when we obtain the measure of the distance, we
have that of the force. The power which operates upon the
wire is called the force of torsion; and the angle formed by the
index in its natural position, and that to which it is brought by
the operation of the twisting power, is called the angle of torsion.
This is accurately measured on the scale ; and assuming that the
force of torsion is equal to the angle of torsion, we are able to
ascertain this force with the most perfect accuracy. Proceeding
upon this principle, a number of experiments were performed
with a view to ascertain the action of different wires, so far as
respected their length, their:thickness, and the nature of the
materials of which they were composed; and he deduced from
them a series of propositions which afford very important data
for estimating the amount of very minute, attractive and repulsive
forces.*
Coulomb had been elected a member of the Academy in 1781,
and now made Paris his residence, devoting himself for some
years almost exclusively to the investigation of the sciences of
electricity and magnetism, more especially in endeavouring to
perfect their theory. In this investigation he was materially
assisted by his torsion balance, and was enabled, by means of it,
to execute some very delicate experiments, which may be con-
sidered as forming the basis of his most important speculations.
He proved by it that electrical attractions and repulsions follow
the general law of the inverse ratio of the squares of the dis-
tances, a law which had been assumed by preceding philoso-
phers as highly probable, and as agreeing generally with the
phenomena, but which had not before obtained the sanction of
-direct experimental proof. In the further prosecution of his
researches on the subject of electricity, Coulomb was induced
to adopt the hypothesis of the two electric fluids, which had been
originally proposed by Dufay, and supported by Symmer, but which,
at least in this country, had been almost unanimously renounced
for the more simple doctrine, which attributes all the effects
* Coulomb’s essay on torsion is in the ninth volume of the Mem, Sgay.
Etrang. and is entitled, ‘‘ Researches theoretical and experimental on the
Force of Torsion, and on the Elasticity of metallic Threads; Application of this
Theory to the Employment of Metals in the Arts and in different philosophical
Experiments; Construction of different Torsion Balances, for the Purpose of
measuring yery small Degrees of Force ; Observations on the Laws of Elasticity
and of Cohesion.” His general theorem is as follows: that the momentum of the
force of torsion is, for threads of the same kind of metal, in the compound ratio of
the angle of torsion, the fourth power of the diameter, and the inverse ratio of
the length of the thread; so that if we call the angle of torsion B, the diameter D,
and the length 1, we shall have as the expression which represents the force of
torsion © :
, Where « is a constant coefficient, which depends upon the natural
stiffness of every metal; this quantity ~, which is invariable for the threads of
each particular metal, may be easily determined by experiment,
F2
84 Biographical Sketch of , [Aveust,
to the excess or defect of a single fluid. Every one must admit
that he defends his hypothesis with much ability, and even with
the precision of mathematical reasoning ; but we must recollect
that the whole is founded upona gratuitous assumption, and that
we are not entitled to employ the agency of two fluids in our
explanations, until we have found it impossible to explain the
phenomena by the supposition of a single fluid. [f, therefore,
the theories are equally plausible, we shall be obliged to reject
the one which proceeds upon the assumption of the greater
number of hypothetical principles.
In the science of magnetism, upon which Coulomb bestowed
a great share of attention, we may observe the same tendenc
to assume imaginary data, upon which, however, he reasons with
much precision, and from which he derives a beautiful and
consistent theory. In order to explain the action of the magnet,
he supposes that all the particles of the instrument are so many
partial magnets, having their opposite poles in contact. The
operation of these poles will, in a great measure, be neutralized
by each other, so that the two extreme poles only will be in a
state’ of activity. This hypothesis, like the one on electricity,
he defended with much ingenuity, and he showed that it was
adequate to explain all the phenomena, but, like the former, it
rests upon a gratuitous foundation. Besides his hypotheses, he,
however, made some important observations on magnetism, espe-
cially those that refer to the effects produced upon it by temper-
ature. He found that the magnetic property of the needle is
diminished as its temperature is increased, and that probably, at
a certain high temperature, it would be entirely destroyed ; this
degree was too high to be ascertained by direct experiment ; but
by employing a theorem of Laplace, it was estimated at the
700° on the centigrade scale, or about 1,450° of Fahrenheit. By
means of the delicate sensibility of his torsion balance, Coulomb
conceived that he was able to detect the magnetic property in
many bodies which were not suspected to contain iron, and was
finally induced to form the conjecture, that magnetism, like
electricity, may exist in all bodies, though it is frequently con-
tained in them in a latent state, and requires a particular com-
bination of circumstances for its development. This idea
appears, however, to have been brought forwards rather as a
speculation, which might be confirmed or refuted by future expe-
riments, than as forming a part of his matured theory, and is
contrary to the opinions that are generally entertained upon the
subject. The experiments and researches of Coulomb on
electricity and magnetism were more directed to the establish-
ment or elucidation of his hypotheses than to the development
of any new facts; so that, although he devoted so much of his
attention to these departments, he has produced in either of
them very little of what can properly be considered as disco-
veries. So far as our information extends, the torsion balance of
1818.] Charles Augustin Coulomb. 85
Coulomb has been very little employed in this country, and even
in France its use appears to have been principally confined to
the author himself, so that its value still rests, in a great measure,
upon his authority.* :
Among the other objects to which Coulomb directed his
attention, we must not omit to mention a memoir which was
published by the Academy in the year 1781 on wind-mills, in
which the author made a great number of experiments on the
mills near Lisle, particularly directing his attention to the form
of the sails, arid the quantity of effect which they were able to
produce by a given force of the wind. A very curious and elabo-
rate paper of Coulomb was published in the Memoirs of the Insti-
tute for the year 1798, detailing numerous experiments on the
quantity of power which a man can exert in the course of a
day, and on the best method of employing his strength. The
author inguires what weight can be best borne during a certain
number of hours, how many loads, and of what size, can be
carried along a horizontal surface ; and how many by the same
person mounting up steps: he afterwards examines the compa-
rative force employed in performing many of the common opera-
tions of labourers, such as pulling a rope, turning a winch, &c.
and endeavours to form accurate estimates on all these points.
We think it doubtful whether all the calculations and deduc-
tions contained in this paper, although derived from experiments,
which were doubtless made with much care and diligence, are
applicable to any useful purposes; so many circumstances,
besides those of a mere mechanical nature, are concerned; and
* Coulomb published, in the whole, seven memoirs on electricity, whichare con-
tained in the Memoirs of the Academy for the years 1785, 1786, 1787, 1788, and
1789. The following may be regarded as among the most important of the pro-
positions which compose his hypothesis of electricity :
1. There exist two electric fluids, one vitreous, and the other resinous,
2. The particles of each of these fluids repel each other.
3. The particles of one of these fluids attract the particles of the other fluid,
4. These attractions and repulsions are in the inverse ratio of the squire of the
distance, 8
5. The electric fluid does not diffuse itself through different bodies in conse-
quence of a chemical affinity, but it is distributed among them when placed in
contact, according to their figure or position, solely by its repulsive force,
6. In conductors, the electric fluid diffuses itself entirely along the surface,
Without penetrating into the interior,
7. In electrics, the fluid penetrates into the interior of the body.
8. The electric force is not produced by impulse, nor by the action of any ex-
traneous impulsive fluid.
9. The electric fluid does not form active atmospheres around bodies, by the
particles of which the phenomena of attraction and repulsion are produced, but
they depend upon the action of the fluid in the body itself.
10. When electricity is excited by friction, or by any other means, the two
bodies acquire different kinds of electricity, the one vitreous, and the other
resinous,
Coulomb supposed the cause of magnetism to be very analogous to that of
electricity; that there were two magnetic fluids; that their particles repel each
other; that the particles of one fluid attract the particles of the other ; that they
act in the inverse ratio of the squares of the distances; but that the fluid is lodged
entirely in the interior of the body.
é
86 Biographical Sketch of C. A. Coulomb. [Aveust
even the mechanical powers of different individuals depend so
much upon causes which are difficult to detect and impossible
to appreciate. In the year 1800, Coulomb published, in the
Memoirs of the Institute, a paper on magnetism, and likewise
one of his most learned essays on the cohesion of fluids. He
employed his torsion balance in the experimental part of the
inquiry ; and he was led by his experiments to form the conclu-
sion, that the resistance which fluids oppose to the slow motion
of their particles upon each other is represented by two terms,
the one proportional to the velocity of the motion, the other to
the square of this velocity.*
The events of Coulomb’s life are few, and not particularly
interesting. The French revolution deprived’ him of some
offices which he had filled under the monarchy, and probably
impaired his private property. At the dissolution of the
Academy he felt no longer any interest in the metropolis, nor
indeed could it be considered as a place of security for any one
distinguished either for talents or for acquisitions of a more inci-
dental kind. He retired for some time to a small estate which
he possessed near Blois, until the violence of the storm was
passed over, when he was recalled to take his place in the Insti-
tute, of which he continued ever after to be an active member.
His death took place in his 70th year, in consequence of a
gradual exhaustion of the nervous system, the immediate result
of a febrile attack, but probably originating in the decay of the
system incident to the decline of life.
The moral character of Coulomb is stated by his eulogist to be
of a high order of excellence; he is said not. only to have
possessed many great virtues, but to have had few defects
to counterbalance them. It is indeed admitted that he had an
impatience of temper, which he often found it difficult to
restrain; but this seems not to have been carried to such a
degree as to render him unamiable, or to disqualify him for any
of the relations of society. The scientific reputation of Coulomb
has been highly estimated by those who are the best qualitied to
judge ofhis merits ; his mathematicallearning was unquestionably
very profound ; and all his writings indicate a clear and correct
method of reasoning, united to a comprehensive view of his
* The following are the titles of the papers published by Coulomb in the
Memoirs of the Institute:
¥V. 2. Experiments on the Circulation of the Sap in Trees.
V. 2. Results of Experiments te determine the Quantity of Power which
can be exerted by Men in their daily Labour, according to the Mode in which they
employ their Strength, :
V. 3. Theoretical and experimental Determination of the Forces which bring
different magnetic Needles to Saturation at their magnetic Meridian.
V. 3. Experiments to determine the Cohesion of Fluids, and the Laws of their
Resistance in very slow Motions,
V.4,. New Method of determining the Inclination of the Magnet.
V.6. Results of the different Methods employed to give Plates and Bars of
Steel the greatest Degree of Magnetism,
1818.] Mrs. Ibbetson on the Effect of burying Weeds. 87
subject. Upon the whole, however, we think it is to be regretted
that he devoted himself so much to the formation of hypotheses ;
and we cannot but regard him as having expended upon refined
speculations a large portion of the ability and exertions which
probably might have been more usefully bestowed upon the
acquisition of real knowledge.
Artic te II.
On the tnjurious Effect of burying Weeds. By Mrs. Ibbetson.
(To the Editors of the Annals of Philosophy.)
GENTLEMEN, May 30, 1818.
To establish facts upon the sure and solid foundation of
repeated experiments, and to discard all those that are derived
from hasty conjecture, and which have not been regularly subjected
to examination, is certainly the duty of a botanist and agricul-
turist. That such an error as I pointed out in my last letter,
and now wish again to combat, should have been persisted in
so long, makes us mourn over the imperfection of our knowledge,
since it might have appeared impossible that so strange a con-
tradiction should have been insisted on, and by many of the first
agriculturists, without their being struck with the strange incon-
sistency of the two facts which are both admitted as true, viz.
that we can bury our vegetables with the certainty of their making
in a few months good manure, fit to nourish plants ; and that we
can put our vegetables into the same earth for the winter months,
to preserve them from decay and from the influence of the frost.
Thus we place them in the same ground, for the same time, and
in almost the same manner, both to destroy and to preserve
them. It is certain that we cannot be successful in both cases;
and as daily experience makes us assured of the latter fact, we
_ should hence have been led to doubt the first. It is admitted
that a few succulent leaves will decay under these circumstances,
but this will not be the case even with the leaves of trees, and
certainly with no species of woody matter. Nor is it a greater
mistake or a more fatal one to agriculture, to dig up our weeds
at a great expense, and then replace them in the earth. A clean
soil is one of the first requisites for good farming ; whereas we
do all in our power, by burying weeds and green crops, to render
the earth as foul as possible. ;
I have in my last letter shown that no vegetable can be of
use as manure till it has passed through all the various steps
which precede decomposition. It has always appeared to me
that there was a strange confusion made by agriculturists in
comparing fresh vegetables with manure ; no two things can be
88 Mrs. Ibbetson on the injurious Effects [Aveust,
more different, yet they reason as if the same operations took
place in both; whereas the first effect to be produced on the
recent plant is to kill it, a process of no small difficulty ; while
the vegetable matter in the manure is certainly dead. It has
passed through the stomach of the animal, has been exposed
there to a high temperature, and yet often without being entirely
decomposed ; since considerable quantities of straws and clover
stalks will be found in dung not yet digested, though exposed
not only to such heat, but to the dissolving power of the gastric
juices. How then can we expect that the earth (so cold in com-
parison) will so soon decompose the vegetable matter, and what
would be a still greater miracle, convert it into mould, when it
has only that sap to assist in its decay, which certainly possesses
no digestive or reducing powers? So far indeed are the vege-
tables when placed in the ground from making manure, that as
soon as the part of the stem which is opposite a branch touches
the earth, roots are directly nourished, and soon protruded ; and
let the process of decay proceed ever so far before they are
buried, it is directly stopped, and the earth is sure to arrest its
progress instead of accelerating the decomposition.
I have now dug up another trench, which has been preserved
since last May,* and not opened till the Ist of the present
month ; it fully confirms all I before made known respecting the
excessive duration of vegetable life, with many curious circum-
stances that greatly assist me in the acquirement of a more
perfect knowledge of plants; while they confirm many of the
most important points that I have before ascertained by means
of dissections, and advanced on vegetable physiology.
All the weeds natural to the soil, and the herbaceous plants,
were growing again, sickly, though firmly ; 1aany of them even
piercing the earth, and appearing just shooting above, and
throwing out fresh germs, except the conium maculatum,
which I have always found to die in the leaves, though not
in the root. I this time made a thorough trial of fresh aquatic
plants; as they decay so immediately on being taken out
of the water, I supposed they would die still quicker under
ground, and would of course form an excellent manure. I,
therefore, buried several plants of potamogeton and ranun-
culus aquatilis, which both appeared to decay as soon as
taken from the water; the pit was opened four months after
burying them, and they were perfectly alive, the first fermenta-
tion having stopped the moment they entered the earth; so that
they appeared as fresh as when they had been taken out of the
water only fora very few hours. This plainly shows that there is
no trusting to any thing but experimental knowledge; for though
a part of these plants had really begun to decay before they were
placed in the earth, yet the fermentation was directly arrested ;
* May, 1817.
1818.] of burying Weeds. 89
the. most.convincing proof that plants, even of the tenderest
kind, and such as most quickly decompose in the air, will
require a very long time to pass through this process in the
earth.
Of the various branches of trees placed in the pit, a number
of them having lost their leaves (at the proper time I suppose)
were full of bud, and those buds were again ready to burst with
their various contents, though the scales were not yet expanded;
a strong confirmation, I think, that the whole process of the
flowers and leaves is formed in the interior, and not in the bark,
as Mr. Knight supposes. Had this been the case, would not
some assistance have been wanted to bestow air, elaborate the
juices, recompose them, and make amends for the light they
must require in the bud? whereas in the interior all is ready
prepared. The root is the complete laboratory of plants, whence
the juices are propelled, and formed according to their respective
affinity. But I have always found that every agricultural expe-
riment only more thoroughly proves and confirms what dissection
had before shown me. {In the oak branches I could detect both
the flower and leaf. The horse chesnut was ready to protrude
its leaves, while the flowers were less backward than they gene-
rally are on the lst of May. But what was most curious, the buds
had none of the glutinous matter which generally surrounds them,
and the scales were completely fixed, which leads me to believe
that the flowers (if the branches had not been taken out of the
earth at this time) would not have protruded, though the leaves
would ; but I shall certamly repeat this experiment next year.
The walnut was quite dead, but the ash was apparently in the
act of giving out its flowers. The alder had many leaf buds,
but few flower buds: they all died soon after being exposed to
the air; a fact which shows how fully unfit a medium the earth
is for making vegetable manure.
The method which the Chinese employ for forming little
diminutive fruit trees for the ornament of their trays, is analogous
to this subject, and shows how easy it is to make the roots of
plants grow in any part. They place a shelf close to the pro-
jecting branch of the tree which they mean thus to reduce ; they
surround it with earth, fixing a bottle of water above with a long
piece of felt hanging out of it; the water then drops on the
earth, constantly keeping it moist, and soon the roots are sure
to shoot from the opposite side, forming radicles enough to
nourish the branch, when it is separated from its parent plant ;
thus a whole tree is by degrees formed into many small ones.
I have found this plan to succeed even with forest trees, as well
as with every sort of fruit tree, one or two excepted. This very
much resembles the manner in which the long roots form in the
earth ; they continually shoot from the part of the stem opposite
to the branch, and in grass from the ends of the shoots; in
pther plants they not only form opposite roots as in trees, but
90 Mrs. Ibbetson on the injurious Effects [Aveust,
the middle root throws out side roots and radicles te nourish any
new shoot that may be formed.
For some time past i have been endeavouring to enforce the
proposition that all plants are favourable to one particular soil,
the tenacious manner in which weeds grow, the difficulty of
killing them, the variety peculiar to each soil, the plants found
in certain situations, and in these only, are strong proofs that soil
is of the first consequence to the existence of a plant. Then
there are many plants that can live only where a peculiar ingre-
dient (either earth or salt) is found. Vegetables near the sea
coast will not thrive unless the soil contains a certain quantity
of muriate of soda. How often have seeds been found totall
dormant in one kind of earth, and when removed into a different
soil have been revived and forced into life? Duhamel gives many
examples of this, and I have myself frequently experienced it.
The parietaria and borage will not thrive except in such soils as
contain nitrate of potash or nitrate of lime ; saintfoi will not
grow well without chalk. I have now tried, for three years past,
many different corns (particularly wheat) in clay, gravel, chalk,
sand, and a rich mould, to see in which each succeeds best,
manuring all alike; and I have found that far from always
choosing the richest soil, there are quite as many do well in the
others ; provided it was their original and proper soil, and con-
genial to their nature, they would give a much larger proportion
than the same wheat would do in a richer soil without this
advantage. J have known sand plants, which were constantly
affected by a sort of dropsy, when put into a rich soil, completely
cured, by being placed in their own original and proper earth. The
red lammas wheat always produced the proportion of nine in sand
to six in clay, when both were equally manured ; and the Taun-
ton wheat will give in arich soil thirteen tc four in a sand. The
blue cone wheat gave ten in clay to only five in sand, and only
seven in arich soil. The Dantzic wheat gave in a sandy loam
the proportions of eleven to seven in clay, and only six in chalk,
all manured alike ; and they maintained nearly the same propor-
tion during the three years that the experiment was continued.
I tried about ten varieties of wheats, and the numbers in that
time varied very little in three successive trials. The fact is still
more decided with respect to clovers, and many other plants, as
lucern, saintfoin, hogs’ peas, beans, canary seed, hops, briza
media, poa pratensis, and trivialis, cynosurus cristatus, which
are all decided chalk plants. In clay we have the hop-trefoils,
cabbage of every kind, festuca calamaria, trifolium procumbens,
poa pratensis, medicago sativa; while festuca fluitans, festuca
elatior, and poa aquatica, grow still better in wet clay. In sandy
soils the most decided plants are found, as the turnip, carrot,
parsnip, beet, annual meadow grass, the cow grass, bird’s-foot
trefoil, avena flavescens. The cow grass is so entirely fed by the
atmosphere, and is, therefore, so truly a 7" plant, that it wants
ee a ee
1818.] of burying Weeds. Ol
but little if any manure. Indeed the advantage of placing a
lant in its own soil is, that it will do with half that quantity.
hen we are thoroughly persuaded and informed what plants
really can take nutriment from the root and those which cannot,
it will be a vast saving to the farmer; for in fact very few sand
plants require manure. I should this summer have completed
the business of my trenches, and the trial of all agricultural
plants, in the five soils above mentioned, if a most severe illness
had not impeded my progress for some time.
If a botanist is asked how are plants fed, he will probably
answer, without hesitation, ‘‘ by means of the radicles which
draw from the earth the nutriment which is consigned to the
root for that purpose ;” but I wish to know how those plants
are to be nourished which have visibly and positively no radicles,
or extremely few? Now this is the case certainly with two very
large collections of plants, the mountain plants and the sand
plants. If these vegetables, therefore, are not fed by the
radicles, they must be supported by the atmosphere : is it not
then of the greatest consequence to know which plants these
are? for if they are wholly or principally supported by the
atmosphere, they cannot certainly require manure. I think
these propositions follow of course, and cannot well be refuted :
to compare the root ofa plant which requires arich soil with the
toot of a sand plant will at once show the difference.
The size of the root is of no consequence whatever ; it is the
small threads which absorb the nourishment, and which alone
show the nature of the plant; the turnip, carrot, and parsnip,
have hardly any of these. The plants of the barren rock have
also no radicles, and the root serves merely to fasten them to the
spot, and to form the corculum of the seed; and this is so deci-
sive that in many annuals, among the sand and mountain plants,
the root is almost dead before the flower appears.
I do not despair that the time will soon arrive when every
farmer will know the plants that exactly suit his soil, that he
will be able chemically to appropriate the manure to the soil,
and will be incapable of burying weeds and of turning in young
crops. I am, Gentlemen, your obliged humble servant,
AcNEs IsBETSON.
ArtIcLe III.
On the Fountainhall Chalybeate Spring. By T. L. Dick, Esq.
F.R.S.E.
(To Dr. Thomson.)
SIR, Fountainhall, Jan. 26, 1818,
ReFERRING you to my communications of April 13 and
July 9, 1816, on the subject of the Fountainhall Chalybeate
92 Mr. Dick on the [AveusT,
- Spring, published in your 43d and 47th numbers, I now- avail
myself of being on the spot to copy for your Annals the follow-
ing continuation of my father’s register of its alternations. The
thermometer was regularly marked as formerly ; but as the tem-
perature of the atmosphere seems to have had no influence at all
in producing the phenomena, it is unnecessary to encumber the
columns with it. ;
~ T have not leisure at present to send you, as formerly, a table
of averages ; and if I had, a glance at the particular items of the
register will convince you that little satisfaction could be had
from such aview. It is evident from the great general increase
of the discharge of water which took place in the month of
February last, and which seems to have continued almost up to
the end of the period embraced by the memoranda, that an
actual increase of the body of water in the mine must have taken
place in that month. :
An attentive observation of the motions of the well has satis-
fied my father that it is much more rapidly affected by any
atmospherical change than the mercurial column. — It must,
therefore, frequently happen, that when both are marked at the
same moment, an apparently anomalous result will be afforded,
owing to the mercury yielding more tardily to the change of
density. A visible alteration as well in the increase as in the
diminution of discharge has often been noticed to take place
whilst the observer has been standing by the fountain.
Register of the alternating Appearances in the Fountainhalt
Chalybeate Spring, continued. N.B. No Measurements made
on Sundays.*
_ June 22, M, R, 233 pints. B, 29-74.—A, 313 pints. B, 29°65. A great deal
of thunder, lightning, and rain, with hail.
24, M, R, 23 pints. B, 29°58.—A, 19 pints. B, 29°63.
25, M, R, 23 pints. B, 29°65,—A, 273 pints. B, 29°58,
26, M, R, 32 pints. B, 29°46.—A, 313 pints. B, 29°39,
27, M, R,20 pints. B, 29°50.—A, 18 pints. B, 29°59,
28, M, R, 16 pints. B, 29°70.—A, 20 pints. B, 29°70.
99, M, R, 223 pints. B, 29°69.—A, 243 pints. B, 29-64.
July 1, M, R, 233 pints. B. 29:39.—A, 213 pints. B, 29:39,
M, R, 233 pints. B,29-37.—A, 233 pints. B, 29°37.
3, M, R, 22 pints. B, 29°37.—A, 213 pints. B, 29°39.
A, M, R, 223 pints. B, 29-40.—A,25 pints. B, 29°39.
5, M, R, 21 pints. B, 29°39.—A, 203 pints. B, 29°42.
6, M, R, 212 pints. B, 29-42.—A, 223 pints. B, 29°40.
8, M, R, 225 pints. B, 29°32. A great fall of rain last night and this
morning.—A, 22 pints. B, 29°32. Rain all day. a
9, M, R, 22 pints. B, 29°35.—A, 233 pints. B, 29°30.
10, M, R, 25 pints. B, 29°25.—A, 253 pints, B, 29-21.
* “The letter R, signifies that the well was running over; F, that it was full;
In.~means the inches down, unless when specified otherwise; M, is morning; and
A, afternoon, It isalso to be noticed that the degree of Fahrenheit’s thermometer
haying been remarked, it is indicated by T; and afterwards the elevation of the
barometer having been also attended to, its height is indicated by-B.”—(See Mr.
Dick’s former paper, Annals, viii. 6.)
1818.]
July 11,
21,
28,
Fountainhall Chalybeate Spring. 93
M, R, 23 pints. B, 29°19. Distant thunder yesterday and the day
before, and this morning a heavy fall of rain.—A, 20 pints, B, 22-29,
Rain,
M, R, 195 pints. B,29:24.—-A,183 pints. B, 29-27.
M, R, 16 pints. B,29-36.—A, 16 pints. B, 29-40.
M, R, 305 pints, B, 29-20.—A, 22 pints. B, 29°24.
M,R, 17 pints, B, 29°29,—A, 194 pints. B, 29°29. Rain.
M, R, 34 pints. B, 29°28.—A, 242 pints. B, 29-20. Thunder and
rain.
M, R, 33 pints. B, 29-04. A great fall of rain last night.—A, 28
pints, B, 29-04. Wind high from S. E, with showers of rain,
M,R, 24 pints. B, 29-04.—A, 191 pints. B, 29-08. Slight showers.
M, R, 103 pints, B, 29-20.—A, 9 pints. B, 29-28.
M, R, 19 pints. B,29-20.—A, 14 pints. B, 29°23. A great fall of
rain,
M, R, 143 pints. B, 29°25.—A, 21 pints. B, 29°25. Showers of
rain.
M, R, 153 pints. B, 29°25.—A, not measured,
M, R, 113 pints. B, 29°30. Rain.—A, 12 pints. B, 29°36.
M, R, 123 pints. B, 29-40.—A, 12 pints. B, 29°45.
M, R, 153 pints. B, 29-43.—A, 18 pints. B, 29°39. A very heavy
fall of rain since twoo’clock, p. m., which still continues.
M, R, 163 pints. B, 29°34.—A, 17 pints. B, 29°30,
M, R, 22 pints. B, 29-22,—A, 22 pints. B, 29°19.
M,R, 19 pints. B,29°19.—A, 18 pints. B, 29-19.
M, R, 143 pints. B, 29-20.—A, 13 pints. B, 29°23.
M, R, 12 pints. B, 29-26.—A, 113 pints. B, 29°28.
M,R, 13 pints. B, 29-29.—A, 103 pints. - B; 29°31.
M,R, 12 pints. B,29:40.—A,11 pints, B, 29°44.
M,R, 10} pints, B, 29-46.—A, 124 pints. B, 29:46,
M, R, 16 pints. B, 29-32,—A, 203 pints. B, 29:29.
M, R, 19 pints. B,29-24.—A, 17 pints. B, 29°24.
M, R, 152 pints, B, 29-23. Rain last night.—A, 103 pints, B, 29°28.
Distant thunder, and a great deal of rain.
M, R, 33 pints, B, 29-40.—A, 113 pints. B, 29:38. Rain in the
afterneon.
M, R, 63 pints. B,29-40.—A, 53 pints. B, 29-49, A high westerly
wind, ; ;
M,R,7pints. B, 29°50.—A, 91 pints. B, 25°52.
M, R, 14 pints. B, 29:-42.—A, 173 pints. B, 29°36, M, R,15pints, B,29'66.—A, 10 pints. B, 29°87.
M, R, 6 pints. B, 29°96.—A, 1] pints. B, 39:03.
2 M,R, 20pints. B, 30°03.—A, 174 pints. B, 30:03.
& & OO
.
1818.] Fountainhall Chalybeate Spring. 101
Oct. 7, M, R, 194 pints. B,30-00.—A, 20 pints. B, 29:94,
8, M, R, 20 pints. B,29°»9.—A, 20 pints. B, 29°86,
9, M, R, 18 pints. B, 29°81.—A, 18 pints. B, 29-75.
10, M,R, 193 pints. B, 29°70.—A, 194 pints. B, 29-70. Rain and east
wind.
11, M, R, 143 pints. B, 29-77.—A, 143 pints. B, 29-80.
' 13, M, R,12 pints. B, 29°96.—A, 134 pints. B, 29:98.
14, M, R,15 pints, B, 29°97—A, 15 pints. B, 29°94.
15, M, R, 193 pints. B, 29°84. Some rain.—A, 15 pints. B, 29°80.
Frequent drizzling showers,
16, M, R, 133 pints. B, 29°83.—A,\134 pints. B, 29°86. A good deal
of rain and some hail since Jast night.
17, M, R, 11 pints. B, 29°91.—A, 11 pints. B, 29°91. .
M, R, 163 pints. B, 29°84. Rain.—A, 19 pints. B, 29°80. Fre-
quent and heavy showers of rain,
20, M, R, 19 pints. B, 29°79.—A, 15% pints. B, 29°78.
21, M, R, 183 pints. B, 29°65.—A, 20 pints. B, 29°50.
22, M, R, 64 pints. B,29'47.—A, 13 pints. B, 29°58,
23, M, R, 6 pints. B, 29°72.—A, 9 pints. B, 29°78.
M, R, 112 pints. B, 29°72.—A, 14 pints. B, 29°67.
25, M, R, 17 pints. B, 29°49.—A, 214 pints. B, 29°38. Brisk S. W.
wind,
27, M, R, 20 pints. B, 29°18.—A, 30 pints. B, 28°98. Ahigh S. W.
wind, with heavy showers of rain.
28, M, R, 23 pints. B, 29°00.—A, 21 pints. B, 29-01. Showers of rain
and sleet,
29, M,R, 17 pints. B,29:01.—A, 144 pints. B, 29°05.
30, M, R, 32 pints. B, 28°80. A high west wind, and heavy showers at
intervals,—A, 32 pints. B, 28°80. Flashes of lightning seen last
night. Storm of wind still unabated.
31, M, R, 14 pints. B, 28-90. A great fall of rain last night, and storm
of wind abated.—A, 4 pints. B, 29°00.
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1818.] Mr. Holt’s Meteorological Journal. 123
_ Societies wishing to make an exchange of Transactions may
address themselves as follows:—‘“‘ To Professor Gotthelf
Fischer, at Moscow.”
Or if they will send a copy of their Transactions, they may
rely with perfect confidence that Professor Fischer will return in
their place the works of the Imperial Society of Naturalists.
ArticLe XI.
Meteorological Journal for the City of Cork. By T. Holt, Esq.
(To Dr. Thomson.)
SIR, y Cork, May. 21, 1818.
I nave been prevented by severe illness from transmitting
the annexed meteorological scale (Plate LXX XII) before this
time, but trust it is not now too late for insertion m the Annals
of Philosophy for July. 1 shall be enabled to complete the
continuation of the scale up to June 30, so as to transmit it by
July 10; and I hope in future to have every quarterly scale ready
in as short a time after its completion.
Permit me to inquire, Sir, if it has been before noticed that a
dilute solution of indigo in sulphuric acid, when treated with
any deoxydizing subject, as bright iron or zinc filings ina closed
vessel, loses its blue colour and remains colourless (or rather of
a very pale green colour) so long as the vessel is kept closed?
The admission of air restores the blue colour, which is again
made to disappear by closing the vessel. As on the addition
of the iron filings hydrogen gas is evolved, the vessel will
require to be occasionally unclosed to let it escape, or it will
endanger the bursting of the vessel.
With much respect, I am, Sir,
Your very obedient, humble servant,
Tuomas Ho tt.
——=zI=—
The fact related by our correspondent is, we believe, new ;
and may, probably, be of considerable practical utility. {t is
well known that indigo becomes a fast colour only when it is
applied in a deoxygenated state ; and this is usually effected by
digesting the indigo in warm or cold water with sulphate of iron
and lime. The blues, however, thus produced, are not equal in
vividness of tint to the Saxon blue, which is made by digesting
the indigo in sulphuric acid, by which it is dissolved without
undergomg any change of colour and consequent deoxygena-
tion. On this account the Saxon blue, however beautiful, is a
colour more or less fugitive, and, therefore, inapplicable to
min purposes. It is possible that by judiciously following up
the hint thrown out by our correspondent, a method may be
12
4
Mr. Holt’s Meteoroiogical Journal.
[Aucus?,
discovered of rendering the beautiful tint of the Saxon blue
equally fast with the ordinary indigo dye.—Ep.
.
Lal
OO sk
teat pet
w=
27,
28.
29,
31.
= ie
wo = SF CHAIHwW
Pied
Gets
2 wr owes
evening. :
Frost last night; bright day; rainy
evening.
Ditto, ditto; dry evening.
Dull, showery day ; windy evening.
. Rainy day, with wind.
. Bright day.
. Rainy day;
snow in evening;
windy.
Showery day.
25. Bright days,
Misty morning ; sleet, with wind.
Showery day.
Snow showers. !
30. Frosty night; rainy days,
Hard frost last night; bright day ;
rainy evening.
FEBRUARY.
Snow last night, and through the
day, with frost.
Ditto.
4,5, Bright, frosty days,
Thaw ; bright day.
. Frost last night; bright day.
Cloudy morning, thaw.
Foggy morning ; bright day ; occa-
sional showers.
Bright day; rain last night;
“showery evening.
Frost last night; bright day ; some
showers.
. Cloudy morning; rainy evening.
‘Showery day; wind.
Gale of wind last night ; showery
day ; bright evening.
REMARKS,
15. Frost last night; ;
JANUARY. aa a showery day;
Cloudy, dry day ; windy evening. 16. Rainy night and showery day.
Ditto, with high wind. }7, Cloudy morning; rainy evening,
Snow this morning; rainy evening. with wind,
Bright morning; cloudy day, || 18. Misty day.
rainy evening. 19, Rainynightand morning; bright day.
Dry, bright day; light shower at || 20. Frost last night; showery day.
noon, 21. Great wind and rain last night;
Frost last night ; bright day ; foggy showery day.
evening, 22, Frost and snow last night: showers
. Duil, misty day. of hail this day.
Bright, dry day. 23. Light snow last night; violent and
Moist day. protracted showers this day.
. Dry, cloudy day ; rainy evening, 24, Frost and snow last night; dry
Stiowery day; rainy evening, morning ; rainy evening.
Misty morning; dull day; rainy |) 25. Violent showers and wind.
evening. 26. Showers ofsnow and wind.
Great wind and rain last night, and || 27. Bright day.
till noon. 28. Showery and windy.
Bright morning; showery day, .
with wind, a 3 - MARCH.
Duii, moist day ; gale of wind. 1. Showery and windy.
Heavy mist through the day; rainy 2. Rainy morning; clear day.
3,4. Very heavy rain, with wind.
al.
Frost and snow last night; heavy
showers of rain and hail.
Bright day ; a few showers.
. Bright morning ; showery day.
Showery day, with snow.
. Frost, snow, and wind, last night,
and this day. ‘
. Frost last night ; showers of snow.
Rainy and windy day,
Snow last night; showery day.
Fine morning; showers of hail;
fine, windy evening.
. Ditto, ditto; rainy evening. 1
. Fine day; some showers of rain;
wet evening,
. Dull, dry day.
. Bright day.
. Dull, dry day.
. Rainy day.
. Bright day ; some hail showers.
Fine bright day ; wet evening, with
thunder and lightning.
Hazy day, with wind.
Clear day ;.some showers of rain
and hail.
. Bright day ; some hail showers.
Ditto; showers of rain.
Ditto, ditto; gale of wind.
Dull, dry day.
Cloudy, with light showers.
Cloudy and showery day;
evening ; rainy night.
Cloudy morning; bright day;
breeze.
Bright day,
fine
1818.] On English and Foreign Copper, Zinc, and Brass. 125
ARTICLE XII.
On English and Foreign Copper, Zinc, arid Brass. By T.Gill, Esq.
(To the Editors of the Annals of Philosophy.)
No. 11, Covent Garden Chambers, —
GENTLEMEN, July 14, 1818,
In Dr. Thomson’s History of Physical Science, published in
your Annals for last month, page 20, speaking of brass, he says,
“ A friend of mine in London, who excels in the construction of
time-pieces, showed me a piece of brass which he valued very
highly. He gave it the name of old Dutch brass, and informed
me that he was in the habit of buying it up whenever he could
find it, and paying much higher prices than were demanded for
modern brass. He was one of those persons who have a much
greater veneration for former ages than for that in which they
happen to live.” He then proceeds to state, that “the old
Dutch brass was much more ductile than Bristol brass with whick
I compared it.” This is surely a much better reason for his
friend’s preference than his “ veneration for former ages ; ” and
he is by no means singular in his opinion, and indeed is well
justified in his practice by the vastly superior purity, ductility,
and malleability of the old Dutch, or, more properly, Nurenberg
brass, which to watch-makers is invaluable, and has long been
employed by them.
The late Mr. Harrison made his celebrated time-pieces of old
Dutch pan brass ; and Mr. Hardy was recently furnished with
some of it by the Board of Longitude, in whose hands it had
been preserved from the time of Mr. Harrison, to make’ a time-
piece with for the Royal Observatory at Greenwich.
When it is considered that the foundation of the very superior
accuracy and delicacy of finish of time-pieces and watches, rests
entirely upon the excellent quality of the steel, and the purity and
malleability of the brass, which they are composed of, it is by
no means singular that watch-makers should prefer that brass,
which so far excels every otherin these important respects.
, The Dutch or Nurenberg brass owes its superior properties to
processes, which are very different to those followed in the
manufacture of brass in this country ; and, indeed, until copper
is brought to that degree of purity and malleability as to be
capable of being beaten into leaves by the gold beater’s process,
similar to Dutch leaf metal; and that zinc shall be entirely,freed
from the lead, tin, &c. with which it may happen to be combined
in the ores by other processes than those usually employed in
this country, namely, of mixing the ores of zinc with copper to
make brass, or of distilling them per descensum to extract the zinc,
which also carries down with it lead, tin, &c. it will be in vain
to hope to make brass equal to the old Dutch brass, and as
capable of being beaten or rolled into thin tinsel, or drawn into
196 Dr. Clarke on the [Aveust;.
fine music wire ; articles for which we are entirely indebted to
Germany.
English brass also differs very considerably from Dutch brass
im its lability to become decomposed and rotten in the time of 2
thaw, possibly from the combined action of cold and moisture,
as happened to a piano-forte making by my friend Mr. T. T.
Hawkins, the frame and strings of which were so exposed when
all those made of English brass wire broke, and the remains of
them were become quite brittle and rotten, and the broken parts
exhibited a dark coloured grain; whilst all those which were
made of foreign brass wire remained unhurt.
i am, however, in hopes that this country will shortly be able
to rival the Nurenberg copper and brass: my father-in-law, Mr.
Wm. E. Sheftield, who has formerly been long in Germany, and
paid particular attention to these important objects, and is a
metallurgist of great skill and experience, having lately manu-
factured copper, zinc, and brass, equal in every respect to the best
foreign; and he is now endeavouring to establish a company for
the erecting of works on a large scale; so that, I trust, this
country will not much longer remain under the stigma of being
excelled in some of its staple articles by the superior quality of
those of other nations.
Another very important advantage resulting from Mr. Shef-
field’s superior method of extracting pure zinc trom its ores, 1s,
that he can employ with profit those poor ores, yielding much less
than 30 per cent. of metal, and which have hitherto been
rejected by the manufacturers of brass in this country to the
great loss of the miners. lam, Gentlemen,
Your most obedient servant,
Tuomas GILL.
ArtTIcLE XIII.
On the colouring Constituent of Roses. In a Letter to the’
Editors. By Edward Daniel. Clarke, LL. D. Professor of
Mineralogy in the University of Cambridge, &c.
GENTLEMEN,
Tne doubts which have been entertained respecting the
colouring principle in flowers, and especially in the blossoms of
the rose, induced me to make a chemical examination of the
substance to which their colour is due. The use to which this co-
louring principle has been applied in the preparation of ¢est paper
renders the inquiry worth a little attention ; and the inferences to
be deduced from it are such as may excite the curiosity of your
readers. Scheele succeeded in proving that the ashes of vege-
tables contain manganese, whence, perhaps, originated the
notion that the red colour of the radish and the green colour of
its leaves, were owing to the presence of this metal. With
1818.] colouring Constituent of Roses. 127
respect, however, to the ved colour of the petals in roses, I have
satisfactorily ascertained that this is due entirely to tron; having
obtained zron and in the metallic state, from an infusion of roses in
distilled water. In proof of this, [ send you a small globule of
ron thus obtamed ; exhibiting a high degree of metallic lustre
when filed, and having all other properties of the metal. The
process by which the metal was extracted shall now be related ;
merely premising that the sort of rose used in these experiments,
was that which botanists term rosa gallica, or common red rose.
After carefully separating the petals from their calices, the
former were placed in a porcelain vessel and covered with warm
distilled water which had been previously boiled ina Florence flask.
In this state they were suffered to remain for eight hours, after
which time the infusion was passed through a filter. A few
drops of muriatic acid were then added, and afterwards liquid
ammonia; when a dark precipitate immediately fell, which,
upon the addition of a little more of the precipitant, and
agitating the fluid, became of a leaf green colour. Being
lett for a couple of hours, a considerable subsidence appeared
at the bottom of the vessel, which, collected upon a filter,
assumed a mud colour, and in this state was left to dry.
After being dried, as much of this mud coloured precipitate
as could be taken from the filter was placed in a test tube
and a little mro-muriatic acid poured upon it. The acid
had been previously proved, and yielded no precipitate or
change of colour to prussiated alkali. Aided by a slight degree
~ of heat, it became of a dark chocolate brown colour, and
began immediately to act upon the precipitate with violent
effervescence ; disengaging a gaseous fluid, which I have not yet
examined, and presently recovering its transparency and colour ;
appearing only somewhat paler. Distilled water was then
added, and being placed over an Argand lamp, the whole of
the liquid was evaporated, nearly to dryness. There then
remained at the bottom of the tube, a muriate of iron, and
distilled water being again added, it was dissolved. Prus-
siate of potass now threw down a beautiful emerald green
precipitate, which, when left to subside, assumed a blue
colour; this being collected on a filter, the remaining liquid
after passing the filter exhibited a topaz yellow hue. As the
grantity of precipitate collected upon the filter was very small,
made use of an expedient which I have found convenient in
experiments upon minute portions of metallic oxides before the
gas blow-pipe, when it was necessary to preserve the quantity
as much as possible from diminution; namely, that of tearing
off the lower point of the filter containing the substance to be
examined, and making it up, while in a moist state, into a pellet
between the fingers. This pellet was then placed within a cavity
in a stick of charcoal and exposed to the flame of a wax candle
urged with a common blow-pipe. In this state, fusion, with
exceedingly minute globules, became apparent; and the de-~
128 On the colouring Constituent of Roses. [Avcust,
oxydation being aided by the addition of a little wax, the whole
gradually ran together into a single globule of more considerable
size ; which remained upon the charcoal exposed to the most
intense heat that could be communicated for several minutes.
Being then suffered to cool, it was so powerfully attracted by
the magnet, that from the preceding observations I had
little doubt of its containing zon m the metallic state; and
upon submitting it to the proper tests, this fact was decided. It
exhibited a high degree of metallic lustre to the action of
the file. As I have since repeated the experiment, and always
with a similar result, [ thought it might gratify your curiosity to
see the cron thus obtained. I have, therefore, sent you one of
these globules fixed into a deal splinter and filed; exhibiting an
appearance like a small zron nail driven into the wood. Butasa
philosophical query suggested by-the whole of the preceding
inquiry, I wish to propose this question: whether the rose tree,
among other instances of the same nature, be not in itself a
living test of the presence of an acid and an alkali in the
lant ; the acid being manifested by the ved colour of the parts
of fructification, and the alkali by the green colour of the leaves ?
The mere circumstance of oxygen existing in a greater proportion
to hydrogen, than is necessary to form water, in a vegetable
substance, is sufficient to explain the presence of an acid; and
alkaline bodies, being substances negatively electrified, an excess
on the side of the hydrogen, explaining the alkaline character of
the leaves, may thence be inferred. That the zon may, perhaps,
exist as a phosphate in the flower seems to be warranted in this;
that the precipitate thrown down by ammonia from the infusion
of roses, when acted upon by a powerful heat, phosphoresces ;
and this compound is still more likely to be detected in those
flowers exhibiting white and blue colours, because these are the
hues of the native phosphates of iron in the mineral state. How-
ever, as the carbonated alkalies dissolve the oxide of iron with
ease, and this solution, which was first noticed by Stahl, is decom-
posed by the alkalies in a caustic state, it may be the same which
acts asa colouring principle in roses. That the base of it is iron
has been here proved. If I have leisure, I will carry this investi-
gation somewhat further; and by extending it to the colouring
principle in other vegetable bodies, endeavour to ascertain
whether iron, so universally prevalent, be the only metal to’
which the varied hues of flowers ought to be ascribed. Hitherto,
the nature of their colouring principle seems to have been un-
known. Thenard says of it, that it has not yet been obtained in a
separate form, although he admits that it is almost always soluble
in water. His words are,* “ Leur principe colorant n’a point
encore été isolé ; il est presque toujours soluble dans Peau.”
I have the honour to be, Gentlemen, yours faithfully,
Cambridge, July 14, 1818. Epwarp Danie CLARKE.
* Traité de Chimie, tome troisieme (1716), p. 376. Paris, 1515.
1818.] MM. Gay-Lussac on the Boiling Point of Fluids. 129
ArtTicLe XIV.
Notice respecting the Fixedness of the Boiling Point of Fluids.
By M. Gay-Lussac.*
In the memoirs of the Academy of Berlin for the year 1785,
p- 2, or in the Annales de Chimie, x. 49, we havea set of expe-
’ yiments by M. Achard, the object of which was to ascertain:
whether the degree of heat of pure boiling water be fixed and’
invariable, independent of the pressure of the atmosphere. He:
deduced two conclusions from his experiments: 1. That, in a
metallic vessel, water has not a fixed point of ebullition, but that,
while it continues boiling, its temperature is constantly varying,.
and that this variation is principally produced by the action of
the air, both upon the sides of the vessel and upon the surface:
of the water, while, in a glass vessel, boiling water has a fixed:
and determinate degree of heat, without the action of the external:
air upon the sides of the vessel producing any change in the:
state of the fluid. 2. That the nature of the vessel has no’
influence upon the degree of heat which the water acquires in)
boiling. There is, however, reason to suppose that M. Achard’s”
experiments are not correct, and that they were so made that
the results cannot be accurately compared together. 20
M. Gay-Lussac, some years ago, observed that a thermometer, '
which marked exactly 212 Fahr. (100 cent.) in water boiling in a»
vessel of tinned iron, did not stop at the same degvee in a vessel’
of glass, although the circumstances appeared in other respects’
quite similar. The difference was about two degrees Fahr. and as.
there seemed no way of accounting for it but the nature of the
vessel, he concluded that water boils sooner in a metallic than”
in a glass vessel.+
Prof. Munche, of Heidelberg, in conjunction with M. Gmelin, .
has made a number of experiments in vessels of different kinds, '
and nearly of the same form, the results of which he conceives’
are unfavourable to M. Gay-Lussac’s position. Upon examining
into the nature of M. Munche’s experiments, M. Gay-Lussacdoes
not, however, conceive that they afford any real objection to his
former opinion; many of the results in fact coincide with it, and
with respect to the rest, they do not appear sufficiently satis-"
factory: to entitle us to form any general conclusion contrary
to it. ;
With respect to the cause of the difference, M. Gay-Lussac:
conjectures that it may depend both upon the conducting power
of the substance of the vessels and upon the polish of the
surfaces. In illustration of the subject he states the following’
* Abridged from the Aun. de Chim, et de Phys. vii. 307. (March, 1818.)
+ Ann, de Chim, Ixxxii. 174,
Vou. XII. N° II. 1
130. M. Gay-Lussac on the Boiling Point of Fluids. [Avausr,
facts. When a mattrass half filled with water is made to boil,
a considerable noise is produced, which indicates that the ebulli-
tion takes place with some difficulty ; large bubbles of vapour
are formed, which rise up from certain points only, and a ther~
mometer plunged into the fluid experiences frequent variations.
If we employ a vessel of tinned iron, the noise is less consider-
able, the bubbles are smaller, but more numerous, the variations
of the thermometer are less considerable, and the boiling point
is lower. We may confirm this observation by boiling water in
a glass vessel, and throwing into it a few filings of iron, when
the ebullition will immediately proceed in the same manner as
in a metallic vessel. If we employ sulphuric acid instead of
water, the difference is more considerable, amounting often to
many degrees.
_ When a fluid is boiled in glass, not only is the ebullition more
slow, but a thermometer plunged into the fluid experiences con+
‘siderable variations, and rises above the real boiling point. It
is supposed that the cohesion or viscidity of a fluid must have
a considerable effect upon its boiling point; for the vapour
which is formed in the interior of a fluid has two forces to over-
come ; the Basis upon its surface, and the cohesion of the
particles. It may be supposed that a solid or a fluid body, the
vapour of which is formed at its surface, may be in a state
of equilibrium with the pressure of the atmosphere, while the
interior portion may acquire a greater degree of heat than that
of the real boiling point, provided the fluid be confined in a
vessel and heated at the lower part, as generally takes place in
the boilmg of fluids. In this case the adhesion of the fluid to
the vessel may be considered as analogous to its viscidity.
The disengagement of an elastic fluid, which is dissolved in
water, is analogous to the ebullition of a fluid. If we take any
brisk fermenting liquor, and wait until the escape of the gas
has ceased, it may be renewed by introducing imto it any solid
substance, as a piece of paper, a crust of bread, a powder, or
even by agitation. The carbonic acid is disengaged principally
where the fiuid touches the glass, and particularly at any part
where there are asperities in the surface.
_ On this principle we explain the sudden starts which some-
times take place in the boiling of fluids. When by any means
the temperature of a fluid is raised above the true boiling point,
it happens that some change occurs, by which a new state of
things is induced, and the superfiuous heat is suddenly disen=
gaged in the form of a great rush of steam. This frequently
occurs to a great degree in distilling sulphuric acid, by which
the vessels are not unfrequently broken, when they are of glass;
this evil may be effectually doe by putting into the retort
some small pieces of platina wire, when the sudden disengage-
ment of gas will be prevented, and consequently the vessels will
not be liable to be broken.
1818.] | Prof. Munche on the Boiling Point of Fluids. 181
The Editors have subjoined an account of Prof. Munche’s
éxperiments, which are referred to by M. Gay-Lussac in the
above paper, and also an extract, on the same subject, from
M. Biot’s Traité de Physique.
=
On the Fixedness of the Boiling Point in Thermometers. By
Professor Munche, of Heidelberg.*
it had.been announced by M. Gay-Lussac, that water boils
in metallic vessels at a temperature of 2°34 Fahr. (1:3 cént.)
lower than in glass vessels; and M. Biot has since confirmed
the observation ; hut the cause of so remarkable a fact has not
been yet ascertained or even examined. M. Munche, in con-
junction with M. Gmelin, undertook to repeat the experiments
and to endeavour to give some explanation of the facts. A
number of vessels of the same form were accordingly prepared,
three inches high and 1:3 inch in diameter, but of different
_materials. Four of them, one of thick leather, another of beech
wood, a third of ivory, and a fourth of 12 folds of thin paper,
could not be. made use of, because they were not sufficiently
good conductors of heat to enable the water to boil. Those that
were employed were of copper, tinned iron, tin, lead, and marble;
they had also a goblet of silver and one of platina, the first ‘3
line thick ; the second, ‘2 only ; also a vessel of varnished delft
ware, 1-6 inch in diameter, two cups in the form of goblets,
one of porcelain and the other of Delft ware, two inches in
diameter, and lastly three medicine phials, of 14 in diameter,
one of white, the other two of green glass. The water in these
different vessels was kept as nearly as possible at. the same
temperature, by placing them in. the same sand bath. The
following are some of the principal results that were obtained.
_ 1. The heat of boiling water may be increased. by the quick-
ness of the fire, so that the thermometer may be raised more
than one degree of Fahr aboye the boiling, poiut on the scale.
2. When the bulb of the thermometer touches the bottom of the
yessel, particularly when it is inserted between the cone which
projects inwards and the sides of the vessel, the thermometer
rises still higher, as much as 1-8 Fahr. 3. The heat of. the water
is diminished, when sand is thrown into it, by some tenths of a
degree ; a small quantity of copper filings, part of which swam
on the water, whilst the remainder fell to the bottom, produced
no effect.
The following table contains the actual temperatures which the
water exhibited in the different vessels when in a state of ebulli-
tion, above or below the degree marked on the scale.
* Abridged from Bibliotheque Universelle, vii. 101. (Feb. 1818) ; and Journal
de Phys, lxxxvi, 243, (March, 1818.)
2
132M. Biot on the. Boiling Point of Fluids. [Aucust,
Substance of the Temperature.
vessels, The thermometer | When the thermometer was half an inch
touching the bottom, below the surface of the water. ~
BREE ies o. 0's cs sn — 0:225 Fahr. — 0:45 Fahr.
Platina. ......| — 0°226 — 1-125
210) 0) a + 0°9 + 0-225
Tinned iron. ...| + 1:24 — 0°34
Marble. ...... + 0-1 — 0°34
LBP LEY: Daa ke Sharad + 0°45 — 0:225
Dita oo. inp eit ote ail — 0°225
Porcelain. ....| + 0°1 — 01
White glass....| + 0°7 0-0
Green glass. ...| + 1:8 + 1:35
Distant. cmt ss + 0°7 0-0
Delft ware ....} + 1°8 + 0°7
Common earth-
enware...... + 1:8 + 0°45
The inside of the metallic vessels, although they were not very
highly polished, were so much so as to have a degree of
metallic lustre. The silver goblet had on one side a black spot
owing to the metal having been a little acted upon in that
part. As soon as the bulb of the thermometer touched this
spot, it rose more than a degree of Fahr. and upon touching the
bottom, it fell to the pomt marked in the table; this curious
observation has been frequently repeated, and always with the
same results.
The author explains the results of his experiments upon the
principle that the heat passes through the bottom of the vessels,
is united to the water, and forms elastic vapour ; but the vapour
thus formed is .a conductor of heat; and besides the caloric
necessary forits formation, contains also a certain quantity of the
same caloric which is capable of affecting the thermometer. The
proportion of the two quantities of heat depends upon the nature
of the substance in which the water is boiled, and also upon the
_ state of the two surfaces, internal and extérnal, so that the
different quality, as well of the substance as of either of the
surfaces, may affect the results, but not so as materially to affect
the accuracy of the thermometer.
———
Extract from M. Biot.
“ There is also some variation in the boiling point according
to the nature of the vessels which we employ, and according to
that of the substances which are mixed with the water, even
when it cannot dissolve them. For this observation we are
1818.] Analyses of Books. 133
indebted to M. Gay-Lussac. In order to verify it by experi-
ment, it is sufficient to put distilled water into a glass vessel,
and cause it to boil; it will be perceived to boil by starts and
with difficulty. Remove it from the fire, by which we must
certainly lower its temperature ; and after an interval of some
seconds, throw into it a small quantity of iron filings ; the fluid
will instantly be thrown into a state of complete ebullition.
These different operations must, however, necessarily tend to
lower its temperature, and consequently the throwing in of the
iron filings must have exercised upon it some unknown action
which facilitates its ebullition.
“This is the general fact: in order to ascertain its degree,
M. Gay-Lussac observed the temperature of the water the
moment when it began to boil in a glass vessel ; he found it to
be 214-2 Fahr. (101-232 cent.) If we throw into the vessel finely
owdered glass, the temperature of ebullition descends to 212°6
Fahr. (100°329 cent.) ; if we put iron filings into it, the temper-
ature descends still lower, and becomes stationary at 212 Fahr.
(100 cent.) M. Gay-Lussac also found that the size of the
vessel has no influence upon the phenomenon, nor had the
greater or less quantity of the iron filings any effect ; water
heated in a metallic vessel boiled at 212 Fahr. (100 cent.)”—
(Biot, Traité de Physique, i. 42.)
ARTICLE XV.
ANALYSES oF Books.
Transactions of the Geological Society, Vols. III. and IV.
(Continued from Vol. xi. p. 453.)
IIl.—2. On the Oxide of Uranium, the Production of Cornwall,
together with a Description and Series of its crystalline Forms.
By Mr. W. Phillips.
In this paper Mr. Phillips describes the varieties of uranite
which have lately been found in Cornwall. This mineral had
been observed to occur rarely in the mine called Carharack,
accompanied with iron ochre, and cubic arseniate of iron. In
1805, Mr. P. discovered uranite at Tincroft mine, near Redruth,
accompanied by pulverulent pecherz, and at Tol Carn mine, about
two miles north of Carharack, also accompanied by pecherz.
The most beautiful specimens of this substance, however, have
recently been discovered in Gunnislake copper mine, near Cal-
lington. The acuteness of Mr. P. has detected a considerable
number of new crystalline varieties among his specimens of
Cornish uranite, which are described in this paper.
- Lit—6. Outlines of the Geology of Cambridgeshire. By the
134 Analyses of Books. [Aucusr,
Rey. J. Hailstone, F.R.S. F.L.S.. Woodwardian Professor in
the University of Cambridge. ;
The upland parts of Cambridgeshire consist of chalk hills,
which, at their northern extremity, appear to rest on an extensive
bed of blue clay, provincially called gault; and on the east, on
the borders of Suftolk and Essex, the chalk is covered by a thick
deposit of clay. The grey or lower chalk is the most abundant
in Cambridgeshire, where it is distinguished by the name of
clunch. When burned, it affords a lime in very high esteem,
and the harder beds form a good building stone, which, from
its standing the fire well, is in great request for the backs of
grates and similar purposes. The clunch and subjacent gault
appear to pass into each other by insensible degrees ; the clunch
first becomes sandy, then assumes the appearance of an argilla-
ceous loam, and as it approaches nearer to the gault, becomes
mixed with green sand, and contains imbedded nodules of a
ferruginous indurated marl. The mass then becomes more uni-
form in structure, and at length is not to be distinguished from
fhe PS argillaceous marl which forms most of the beds of
ault,
. III.—7. Some Observations ona Bed of Trap, occurring inthe
Colliery of Birch Hill, near Walsall, in Staffordshire. By
Arthur Aikin, Sec. G.S.
The following are the circumstances described in this oa
‘A vertical dyke of Trap intersects part of the colliery at Birch
Hill, and comes up to the surface, forming a long, low mound
from 70 to 100 yards broad, and known by the name of the
green rock fault. A wedge-shaped lateral prolongation of this
trap has apparently intruded itself between two of the coal
strata, which in those parts of the colliery where the trap does
not occur are found in contact with each other. The bed which
covers the trap is shale, containing subordinate beds of iron-
stone, and presents no peculiar appearances, but the three beds
which lie below the trap, namely, sandstone, shale, and coal, of
the aggregate thickness of about 71 feet, differ remarkably from
the same beds where they are not covered by trap. The sand-
stone is broken, and angular pieces of the shale are imbedded in
it ; the structure of the sandstone is more compact ; it is harder
and of greater specific gravity. The shale is much indurated,
has a glossy metallic lustre, and is destitute of bitumen. The
coal has a shining, somewhat iridescent lustre, is entirely desti-
tute of bitumen, and when put in the fire, burns rapidly, like
common cinder; but where the coal is not covered by the trap,
it grin the usual characters of common bituminous stone
coal.
TII.—8. A Geological Description of Glen Tilt. By J.
' M‘Culloch, M.D. F.L.S. Pres. G. S. &e.
The interesting appearances in Glen Tilt, first we believe
observed by the late Dr. Hutton, have long aflorded materials
1818.) Geological Transactions, Vols. III and IV. 135
for controversy to Scottish geologists. The observers, to what-
ever party they have attached themselves, fascinated as it were
by the intricate and remarkable phenomena laid bare by the
course of the torrent, have for the most part confined their atten-
tion to the bed of the stream and its immediate banks: hence
has arisen some misrepresentation which a more excursive
research would have avoided. The following is an abstract of
the observations made by Dr. M‘Culloch.
From the junction of the Tarff to the bridge of Tilt, near Blair
Athol, a distance of about 10 miles, the glen extends in a
direction about N.E. and S.W. The mountains which form the
north-western side consist chiefly of granite, generally of a red
colour, but in some places passing insensibly into a variety of a
grey colour, and containing crystals of hornblende. This latter
may, on a superficial view, be mistaken for sienite, but differs
from that rock in containing a large proportion of quartz, and but
little felspar ; it also frequently contains epidote, and numerous,
though minute, crystals ofsphene. Insulated patches of quartz-
rock, schist, and limestone, interstratified with each other, may
be seen resting on the granite ; which beds, on the south-eastern
‘side of the glen, cover the whole surface to the entire exclusion.
of the granite. The bed of the torrent, and its immediate banks
through the greater part of the space already mentioned, form
the line along which the granite emerges from beneath the stra-
tified rocks, and where the following very striking appearances
present themselves.
Veins of granite traverse the schist and quartz rock and pass
into the accompanying limestone. These veins are occasionally
of large size, in which case they may often be clearly traced into
the main body of the granite; often, however, they appear to
originate and end in the limestone, and present the aspect of
detached lumps and irregular processes rather than of veins.
Sometimes they intersect and reticulate both the schist and
limestone, diminishing to the tenuity of a thread or a leaf of
paper. Sometimes thin lamine of granite may be observed
arranged parallel to the beds of limestone, and following every
fiexure and contortion which it undergoes with the most perfect
regularity; sometimes, again, minute points of the same red
siliceous matter as constitutes the thin veins of granite occur
inhering in the limestone, and from their minuteness are scarcely
to be detected, unless where the calcareous base has been worn
down by the action of water, in which case, these points are
left protruding, and thus give a rough or echinated character to
the surface of the limestone, Occasionally the limestone occurs
apparently unstratified and in the state of crystalline marble, of
a white colour, partially tinged by yellow and pale green. Where
the marble is at the greatest distance from the granite, it ditters
little or nothing in hardness or composition from ordinary speci-
136 Analyses of Books. [Aveusr,
mens of this substance. But wherever it approaches or comes
in contact with the granite, it becomes highly indurated, effer-
vesces slowly with acids, and gives on analysis a large propor-
tion of siliceous matter. All the varieties of this marble contain
more or less of mica, which excludes it from the statuary’s use,
though it is perfectly applicable to various architectural and
‘ornamental purposes to which its greyish hue and low tone of
colour are more applicable than the dazzling white of the
‘Carrara marble. Steatite and noble serpentine are found mixed
swith and imbedded in this marble, as also is the case with tremo-
dite, which latter mineral besides constitutes thin beds alternat-
img with the marble. Beds of sahlite, affording several varieties
_of this substance, are likewise associated with the limestone.
From the above and other similar appearances, Dr. M.
concludes the general structure of this part of the country to be
composed of regular, even, and defined alternations of quartz
rock, schist, and limestone, resting on granite, the immediate
covering of the granite being sometimes one, sometimes another
of the superincumbent stratified beds. In every instance where
the granite is actually visible in contact with the neighbouring
rocks, great confusion and disturbance are apparent, consisting
in a general mixture of all the stratified rocks with the granite,
and a total discomposure of their regularity, being at the same
.time accompanied by the passage of minute veins from the mass
.of granite into the stratified rocks. Where on the contrary the
beds lie out of the immediate vicinity of the granite, they retain
their parallelism and regularity, its influence appearing to extend
-to a yery short distance beyond the poimt of actual contact.
. TIL—9. Sketch of the Geology of the south-western Part of
Somersetshire. By L. Horner, Esq. F.R.S.
The high part of the district here described, including the
Quantock hills, is elevated from, 800 to 1,600 feet above the
level of the sea, and is occupied, generally speaking, by a grey-
wacke formation, consisting of sandstones, more or less clayey
and fissile, of schist, coarse or fine slaty, and often inclosing
thick irregular beds of limestone, abounding for the most part
in madrepores. Curvatures, contortions, and fractures, are of
frequent occurrence in the various beds of this formation, indicat-
ing it to have been subjected to the violent impulse of some
unknown agent, while the beds still preserved a greater or less
degree of plasticity.
The rock on which this greywacke rests is unknown; in a
single instance Mr, H. discovered a vein of granite traversing
the slate, and as usual producing a degree of induration on
those parts of the rock which are actually or nearly in contact
with it. |
. The greywacke is bounded in every direction by that deposit,
galled by the name of red rock, red marl, red ground, &c, which
1818.) Proceedings of Philosophical Societies. 137
consists of beds of conglomerate, of red sandstone, and of a red
and greenish grey indurated marl, in which rock salt and brine
springs are usually found.
On the north of the red sandstone, and occupying the prin-
cipal part of the coast from Minehead to the mouth of the Parret,
‘occur beds of lias limestone.. The junction of the red sandstone
and lias is very apparent on many parts of the coast; but such
is the disturbance and mutual. intermixture ‘of these rocks, that it
is by no means easy to obtaina satisfactory proof of their relative
superposition with regard to each other. The upper beds of the
lias are of a light blue colour, which, by calcination, or long
exposure to the atmosphere, passes to a yellowish buff colour :
the lime which they produce is not in much estimation for agri-
cultural purposes, but has the valuable property of forming a
cement, which sets under water. The limestone of the lower
beds of the lias is of a much darker colour, is very fetid when
Tubbed or struck, and yields a lime in great estimation as a
manure.
The lamellar blue clay, which alternates with the beds of lias,
incloses lenticular concretions of clayey limestone, many of
which when broken present the structure cf septaria, the sparry
matter of the veins being in some instances calcareous spar, in
others sulphate of strontian, occasionally in well defined crystals.
The red sandstone on the coast west of Watchett contains
much gypsum, inclosing grains of sand and small pieces of
quartz ; but no rock salt has hitherto been observed in it.
- Three miles west of the mouth of the Parret the coast consists of
deep and almost fluid mud, containing many trunks and branches
of trees, of which some of the former still retain their natural
position. Much of the timber has of late years been carried off
Y the neighbouring inhabitants for fuel and other purposes.
How far this submarine forest extends to sea is unknown.
Ill.—10. Description of a Clinometer. By the Right Hon.
Lord Webb Seymour, F.R.S. &c.
The description of this instrument for measuring the inclina-
tion of strata cannot be understood without the accompanying
plates.
(To be continued, )
ARTICLE XVI.
Proceedings of Philosophical Societies.
GEOLOGICAL SOCIETY.
May 15.—The reading of a paper, by Thomas Weaver, Esq.
“On the Geological Relations of the East of Ireland,” was
commenced.
June 5.—The reading of Mr. Weaver’s paper was continued.
" 2
138 Proceedings of Philosophical Societies. [Avewst,
June 19.—The reading of Mr. Weaver’s paper was concluded.
The district described in this paper is bounded on the E. by
the Irish channel, and on the S. and W. by the mountains which
confine the Suire and Shannon, and on the N. by the hills of
South Meath, Cavan, and Longford, and by a hve. produced
from thence to the bay of Galway. Itis about 100 Insh mules
from N. to. and 60 to 90 from E. to W. comprehending about
1 part of the island. It may be divided into primary tracts,
comprehending
Granite,
Mica slate,
Clay slate,
Transition tracts,
Floetz tracts, and
Alluvial tracts.
_ The granite principally occupies an extended line passing
through the counties of Wickiow and Carlow, and is succeeded
in the northern portion by mica slate, resting on its eastern and
western sides; but towards its southern extremity, the mica
slate is wanting; and it is found m contact on the eastern side
with clay slate, and on the western with the floetz limestone,
The clay slate is found also occupying a large part of the county
of Waterford, and occurs again to the westward, in the counties
of Clare and Tipperary.
These primary rocks are found variously stratified with each
other, and with trap, porphyry, and greywacke, both compact
and slaty.
The sat to which the author has assigned the application
of transition tract, is of very limited extent, and occupies the
-northern part of the county of Dublin, and the western part of
Meath. It consists of clay slate conglomerate, greywacke, and
greywacke slate, interstratified with limestone, trap, and por-
yry- :
The floctz tract is much more considerable, and may be
divided into
The old sandstone, '
The floetz limestone, and
The coal district.
The old sandstone is much dispersed, and is found resting on
granite, clayslate, and greywacke, and occurs sometimes im
isolated portions, and sometimes forming mountain masses.
The floetz limestone is the most extensive formation in Ireland.
With the exception of the counties of Derry, Antrim, and Wick-
low, there is no part of the island in which it does not more or
less prevail. It exhibits considerable variety of character m
colour, structure, and hardness, and is found both in unmixed
and continuous strata, as well as associated “7 other rocks,
1818.} Royal Academy of Sciences. 139
and sweeps round every mountain tract, filling up all the inter-
vening spaces.
The coal district of Leinster forms a range of low hills, placed
upon and elevated above the floetz limestone. It is about six
miles broad and about 18 in length, and consists of coal alter-
nating with shale and great stones, and resting on a bed of fine
clay.
The alluvial tract contains with the limestone gravel, some
valuable and extensive beds of marl, containing the remains of
the Irish elk, and, in one instance, of the red deer. But the
bones of a complete skeleton of the elk have not yet been found
together.
At the same meeting, a paper, by H. Warburton, Esq. was
read, “ On Chromate of Iron as a volcanic Production.”
In the Journal de Physique for March, 1818, the Chevalier
Sementini describes some red earth, which fell in Calabria,
mixed with crystals of pyroxene, and found on analysis to con-
tain chrome, which M. Sementini considers indicative of
meteoric .origin.* Mr. Warburton observes that pyroxene is
almost.exclusively of volcanic origin, and he refers to a specimen
of olivine presented by him last November to the Society, from
the extinct volcanoes near Geroldstein, coloured green by oxide
of chrome, and accompanied by grains of chromate of iron.
From these circumstances, Mr. Warburton infers the greater
probability that the earth in question was of volcanic origin.
ROYAL ACADEMY OF SCIENCES AT PARIS.
March 2.—M. Vallée presented in manuscript a treatise on
descriptive geometry accompanied by drawings. |
The committee appointed by the academy to adjudge the
prize offered in the class of physics to the best essay on the
thermometric scale and the laws of the transmission of heat,
made their report. The memoir which, in the unanimous opinion
of the committee, was worthy of the prize, proved, on opening
the accompanying sealed note, to be the joint production of
M. Petit, Professor at the Ecole Polytechnique, and ofM. Dulong,
Professor at the Ecole Royale of Alfort.
M. Geoffroy-Saint-Hilaire read a memoir on the Os Hyoides
of the Mammalia.
M. Manouri-Dectot read a memoir on a new Steam Engine,
and M. Delille read one on the Persea.
March 9.—M. Geoffroy-Saint-Hilaire presented a printed copy
of a memoir, “ On the Unity of Composition and Identity of the
Substances composing the respiratory Organs in Animals with
Vertebre.”
M. FP. H. da Locle communicated a2 memoir on the Isochro-
nism of Spiral Springs.
' * See Annals of Philosophy, xi. 466.
140 Proceedings of Philosophical Societies. [Aucust,
. M. Chaptal, in the name of the committee to whom the
subject was referred, gave an account of the memoirs that had
been received in claim of the prize offered by the late M. Ravrio
for the best method of protecting gilders from the fumes of the
mercury employed in their art. The prize was adjudged to
M. Darcet, Verificateur General of the Mint.
M. Legendre anounced that the papers sent in claim of the
prize for the Theorem of Fermat are not possessed of sufficient
merit. :
M. Humboldt read a memoir on the Arbre de la Vache (Cow
Tree).
M. Gillet-de-Laumont announced the discovery of a new alkali
in the petalite of the mine of Uto in Sweden.
The reading of a memoir by M. Beudant, on the Varieties of
Form in Crystals of the same Species, was begun. '
The Academy adjudged the annual prize founded by M. de
Lalande to Mr. Pond, Astronomer Royal at Greenwich, for his
investigations on the annual parallax of the stars.
March 16.—M. Delambre read the eloges of MM. Rochon
and Messier, and M. Cuvier read those of Werner and of
Desmaretz.
M. Girard read a memoir, entitled “ An Historical View of
Inland Navigation.”
_ March 23.—A letter of M. Berzelius addressed to M. Berthollet
was read, announcing the discovery of two new substances.
M. Vauquelin read a note on the same subject.
The Marshal Duke of Ragusa made a report on a work by
M. Dupin, entitled ‘‘ An Essay on the Progress of Artillery, and
of Military Engineering in Great Britain.”
M. Dupin has examined with attention, and given a descrip-
tion of the principal military estabhshments m England, viz.
Woolwich, Portsmouth, Chatham, &c.
The great laboratory and military manufactory of the state, is
at Woolwich, in which arsenal are more than 10,000 cannon,
besides a vast number of mortars, aud other species of artillery.
Portsmouth and Chatham are fortified, but offer nothing in this
respect worthy of remark.
_ Phe steam engine and the hydraulic press are at present the
principal moving powers employed in England; and it is not
without surprise that we see engines performing the work of 200
or 300 horses without confusion and without noise. The
hydraulic press of Pascal, brought to perfection by Bramah, was
found during the late war to be eminently serviceable in reduc-
ing the bulk of hay, and of stores and equipments of various
cinds.
The application of rockets to military purposes is not consi-
dered by M. Dupin as of much importance ; but the eftect of the
Shrapnel shells is acknowledged by him to be most formidable.
The reading of M. Beudant’s memoir was continued.
1818.] > .° Royal Academy of Sciences. - 141
March 30.—M. de Varennes delivered in a description of a
species of incombustible cloth, which was referred to a com-
mittee. ;
M. Desfontaines made a report on M. Dellile’s memoir on the
Persea. 3
The persea was a: tree formerly cultivated in Egypt for the
sake of its fruit, and of which Theophrastus, Dioscorides, Pliny,
and other ancient naturalists have made mention. The former
of these writers thus describes it. ‘‘ There grows in Egypt a
remarkable tree called persea. In its leaves, flowers, and man-
ner of growth, it resembles the pear tree; but differs from it
in being evergreen. It produces fruit in abundance, which
ripens about the time of the Etesian winds. When the fruit is
intended to be kept, it is gathered before it is quite ripe. In
this state it is of a greenish colour, and in form like an almond
or elongated pear : the pulp, which is soft, agreeable to the taste,
and of easy digestion, incloses a stone like that of a plum, but
smaller and harder. The wood of the persea is dense, and of a
fine black colour, and is used for making tables and statues.”
Many modern naturalists have sought for this tree, but without
success. M. de Sacy, in his translation of the Description of
Egypt, by Abdallatif, an Arabian physician, proves. that the
tree described by the ancient writers of that nation under the
name of lebakh, is the persea of Theophrastus. This tree has
for some ages past disappeared from lower Egypt ; but M. Dellile
thinks that he has recognized it in the Xymenia Egyptiaca of
Linneus, of which he saw one specimen in a garden at Cairo,
and two others in Upper Egypt. It is, however, common in
Nubia and Abyssinia, where it is known by the name of glig.
The committee think the opinion of M. Dellile to be in all pro-
bability well founded, and propose that his memoir should be
inserted among the Scavans étrangers. ~
M. Poisson read a memoir on the Motion of Elastic Fluids.
The reading of M. Beudant’s memoir was concluded, and was
referred to a committee.
M. Fresnel read a memoir on the Colours produced in homo-
geneous Fluids by polarized Light. _ :
M. Moreau de Jonnés read a memoir on the Coluber Cursor of
Martinique. |
April 6.—M. Dupin presented in manuscript that part of his
Voyage en Angleterre relating to the construction of ships ; it
was referred to a committee. '
M. de Lavalette gave in a supplementary letter on the’
musical notation of the Greeks; this also was referred to a
. committee. r
M. Biot presented a specimen of the glass employed by Mr.
Stevenson in the ‘Bell-rock light-house in Scotland. It is a red:
glass, the colour of which is occasioned by a thin, superficial)
coating of metallic oxide. The cost is considerable ; and the
reporter suggests that hollow glasses of any desired form, and
142 Proceedings of Philosophical Societies. [Aveust,
filled with coloured fluids, like those which ornament the shop
windows of druggists, would, in all probability, answer the end
at a much less expense. - ;
M. Gillet de Laumont stated that lithion occurs much more
abundantly in the triphane than in the petalite.
M. Beauvois read a description of an aggregation of stones
observed in the United States, and known by the name of the
natural wall.
M. Geoffray-Saint-Hilaire continued the reading of his memoir
on the Pulmonary Organs.
M. Constantio, a Portuguese physician, read a memoir, in
which he attributes a very marvellous effect to a certain balsain
invented by M. Malati, a Spanish physician; which was
referred to a committee.
April 13.—M. Moreau de Jonnés read a memoir on the Calca-
reous Islands of the West Indies.
A series of observations by M. Dupetit-Thouars on the Effect
of Frost on Vegetables, was referred to a joint committee of
botany and agriculture.
M. Girard read a report on a machine invented by MM.
Lacroix and Peulvay, a mode! of which was presented to the
Academy. . pet i
April 20.—A sealed packet containing theoretical views on
certain phenomena of light, by M. Fresnel, was deposited with
the Academy.
M. Rebours presented a new instrument, called by him micro-
telescope ; which was referred to a committee.
M. Peiletier read a memoir on Cochineal. A bed for the use
of women in labour invented by M. Rouget was referred to a
committee of Surgeons.
The continuation of “ Meteorological Observations made at
Alais, during the year 1817, by M. Hombres-Firmas,” was read.
April 27.—M. Rauzon de Passan sent a new letter on the
Theorem of Archimedes respecting the ratio of the cylinder and
the inscribed sphere ; referred to a committee.
M. Painsot read a memoir on the theory of numbers, entitled
“ An Analytical Representation of the Remainders of Powers,
by the Formula of imaginary Roots of Unity.” :
M. Julien-le-Roi presented the description of a carriage
invented by him ; referred to a committee.
. M. Richerand read a memoir on a successful operation, in
which portions of three ribs were removed, and the pleura was
wounded.
_ M. Dellile’s memoir on the Date Palm, cultivated in Egypt,
was referred to a committee.
_M. Colin presented an instrument of his invention for the
purpose of facilitating the circular incision recommended for
curing the bleeding of the vine.
A memoir was read, by M. France, on the Shells composing
the Genus Cabochon,
1818.] Scientific Intelligence. . 14
Artictre XVII.
SCIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS
CONNECTED WITH SCIENCE.
I, Effect of Camphor on heated platina Wire.
The method of keeping a platina wire incandescent by means
of the vapour of alcohol has been fully described in a former
number of this journal. Sir H. Davy has discovered that the
vapour of camphor will produce a similar effect. For this pur-
pose lay a piece of camphor, or a few fragments on any conve-
~ nient support, and place upon it a coil of platina wire made red’
hot; the wire will immediately begin to glow, and will continue
in that state as long as any of the camphor remams.
Il. Silver from Luna Cornea.
The following method of obtaining metallic silver from lun
cornea has been discovered by M. Arfvedson:
Put some grains of zinc into a conical glass, and cover them
with luna cornea; then pour in carefully some diluted sulphuric
acid. The hydrogen gas thus liberated will soon reduce the
silver to the metallic state. .
Ili. Geological Situation of the Gems of Ceylon.
From a letter of Dr. J. Davy’s, inserted in the last number of
the Royal Institution Journal, it appears that gems abound in
the district of Matura, situated in the south of the island of
Ceylon. They are procured by the natives from alluvial soil ;
but the native repository of the sapphire, the ruby, the cat’s eye,
the different varieties of zircon, and cinnamon stone, has been.
ascertained by Dr. D. to be gneiss.
IV. Geological Description of Adam’s Peak in the Island of
Ceylon. By Dr. Davy.*
“ Geologically considered, the mountain may be said to be
composed of gneiss. The rock on the top, on which is the
impression of the foot, is gneiss of a very fine grain. It abounds
in quartz. It is hard and compact, of a grey colour, and only
in mass exhibits a flaky structure. A little below, felspar pre-
dominates, and the rock is richin garnets. Here it is in a soft
state; and towards the surface rapidly decomposing. Still
lower, hornblende prevails, and in so large a proportion that
articular masses may be called hornblende rock. Near the
ttom, felspar again predominates, and the rock contains much
molybdena disseminated through it. Besides, in different
places the rock exhibits other peculiarities ; here abounding in
* Extracted from an account of Adam’s Peak in the Journ, of Science and the
is, v,
144 Scientific Intelligence. [Aucust,
quartz, in a massive form; there in mica, in large plates, and
very frequently rich in iron and cinnamon-stone. Garnet,
traces of the ruby, and adularia, were the only minerals which I
observed ; but I have no doubt more minute examination would
have detected others, and particularly the corundum, all the
varieties of which, including the finest blue sapphires, are found
in considerable abundance in the alluvial country at the foot of
the mountains.” eae
Dr. Davy remarks that the height of Adam’s Peak has been»
much exaggerated, and that the estimate of 15-000 feet is evidently -
imcorrect. From his barometrical observations, he is disposed
to think that it does not exceed 6348 feet above the level of the -
sea; but as the author himself acknowledges, this conclusion -
cannot be regarded as more than an approximation to the truth,
as there was no barometer at the bottom of the mountain to:
compare with the one at the top. This deficiency is, however,
less important inthe tropical regions, where the weight and
temperature of the atmosphere are so nearly stationary.
V. On the Acidity of Tungsten and Uranium when saturated
with Oxygen. By M.Chevreul.* ,
When the tungstate of ammonia is calcined, a yellow powder:
remains, which is tungsten saturated with oxygen. Many.
chemists having observed that this powder had no action upon
litmus, have concluded that tungsten saturated with oxygen was
not properly entitled to the appellation of an acid. M.Chevreul
wishing to assure himself of the fact, whether tungsten satu-
rated with oxygen, which had no sensible affinity for acids, but’
which, on the contrary, hada very decided one for alkalies, did’
not redden litmus, heated tunstate of ammonia with litmus,
when he observed that the ammonia was disengaged, and that’
the litmus was reddened ; hence he concludes that what has’
been called tungstic acid possesses a real acidity. M.Chevreul,
when he communicated this observation to the Philomathic
Society, stated that smce he had performed the experiment,
he found a similar remark in the memoir of the D’Elhuyarts. ~
The peroxide of uranium is known to have the property of
being dissolved in the sub-carbonate of potash, but it is not
generally known that the native peroxide of uranium, and that
which is formed fromthe nitrate, after having been decomposed
by heat, causes litmus to assume the red colour; likewise that’
the peroxide of uranium heated with a solution of the. sub-.
carbonate of potash, is dissolved in it without disengaging any
carbonic acid; and that the solution, which-has a beautiful”
lemon yellow colour, when sufficiently concentrated, affords
crystals of the same colour. :
M. Chevreul has observed that the peroxide of uran? 1m causes
* Bulletin des Sciences for 1818, p. 20,
1818.] Scientific Intélligence.: 145
hematine to assume the blue colour, a circumstance which con-
nects it with the salitiable bases.
VI. Method of making Salt in the Great Loo-choo Island.*
Near the sea, large level fields are rolled or beat so as to have
ahard surface. Over this is strewn a sort of sandy black earth,
forming a coat about a quarter of an inch thick. Rakes and
other implements are used to make it of a uniform thickness,
but it is not pressed down. During the heat of the day, men
-are employed to bring water in tubs from the sea, which is
sprinkled over these fields by means of a short scoop. The heat
of the sun, in a short time, evaporates the water, and the salt is
left in the sand, which is scraped up and put into raised reser-
voirs of masonry about six feet by four, and five deep. When
the receiver is full of the sand, sea water is poured on the top;
and this, in its way down, carries with it the salt left by the
evaporation. When it runs out below at a small hole, itis a
very strong brine; this is reduced to salt by being boiled in
vessels about three feet wide and one deep. The cakes result-
ing from this operation are an inch and a half in thickness.
—i<-
The above account will be considered interesting, both as
exhibiting the degree of perfection to which the arts of hfe have
been carried in that remote and insulated country, and as being
essentially the very same process which is practised on the
western coast of France, particularly in Lower Normandy, and
at the isles of Oleron and Rhé.—(See Journ. des Mines, No. 7,
p- 61; Encyc. Meth., Arts and Metiers. Article Salines.—Ep.
VIL. On Street Illumination. By John Millington, Esq.+
After remarking upon the very imperfect state of the old oil
lamps that are employed in the streets of London, and the
important improvement made upon them, first by Lord Coch-
rane’s lamp, in which the combustion is promoted by a current
of air entering at the bottom of the glass, and still more by the
use of coal gas, Mr. Millington proposes an alteration in the
reflectors that are employed. As the author properly observes,
the object is not to produce a concentration of light, but an
equable diffusion of it, exactly the reverse of the effect which is
produced by the lenses which still dazzle the eyes in some parts
of the metropolis. The reflectors employed by Lord Cochrane,
although the best that have been employed so far as their form
is concerned, are defective from the material of which they are
composed. This is tinned iron, which although it is at first
sufficiently brilliant, yet it soon loses its brightness by the smoke
which adheres to it, or by the friction necessary for keeping it
* Extracted from Capt. Hall’s ** Account of a Voyage of Discovery to the
West Coast of Corea, and the great Loo-choo Island.”
+ Abridg d from the Journal of Science and the Arts, v. 17.
Vou. XII. N° IT, K
146 Scientific Intelligence. [| Aveust,
clean. As a substitute for the tin, Mr. Millington proposes to
employ glazed white earthen ware ; it has a strong reflecting
surface ; is very easily kept clean, is not expensive, and might,
he conceives, be so fixed, as not to be lable to be broken. For
the purpose of disposing of the light in the most useful manner,
the lower surface of the reflector, which is placed over the lamp,
should either be flat or curved outwards, so as to disperse the
rays, unless the object be to concentrate the light in any parti-
cular spot, when a concave dish, forming a portion of a hollow
dish, may be used.
VIII. On the Colour of Bodies. By M. Prevost.
A new hypothesis respecting the cause of colour in bodies has
been lately proposed by M. Ben. Prevost, according to which it
is supposed that the effect depends not upon reflection but upon
radiation. It was formerly supposed that the different rays
which compose white light, were all of them, except those which
produce the colour of the body, absorbed by it, whilst these were
reflected ; M. Prevost, however, conceives that coloured bodies
reflect a portion of the light in its white or compound state, and
that they decompose a part of that which penetrates their sub-
stance into two new parts, one of which remains in the body, and
the other radiates from all parts of their surface. The colour of
bodies, as we commonly see it, is rendered pale by the white
light which is mixed with it; but it may be deprived of this by a
series of mutual reflections and decompositions, so as consider-
ably to augment the intensity of the Golour.. If, for example, we
receive successively the image of a plate of gold which is
polished and illuminated by a bright light, upon a second plate,
and this image upon a third, &c. we may, after 12 or 18 of these
successive reflections, procure a deep red orange, which is
probably the real colour of gold. By applying the same process
to copper, we procure a colour which approaches to that of scar-
let ; silver becomes of a beautiful yellow ; tinned iron exhibits a
yellow gear than that which is generally ascribed to gold ; and
m short M. Prevost concludes from his experiments that there
is no metal which is properly white or grey; but that they all of
them possess some decided brilliant colour.
IX. M. Depretz’ Experiments on the Cooling of Metals.
A series of experiments have been performed by M. Depretz
on the cooling of metals, which appear to have been conducted
with considerable attention to accuracy. His object was to
examine their specific heat and their conducting power, which
pout although they had been made the subject of experiment,
1e conceived had not been ascertained with correctness, because
the experimentalists had not been aware of the effects of radia-
tion from polished surfaces. He employed balls of metal, with
a cavity in the center adapted to a thermometer ; filings of the
metals. were placed round the bulb so as to fill up the cavity, and
1818.] Scientific Intelligence. 147
the apparatus was heated by a current of hot air. Of the results
of his experiments, we hope to give an account in a future num-
ber of the Annals.
X. M. Horner’s Photometer.*
M. Horner, of Zurich, has proposed a new instrument for
measuring the intensity of light, which is very cheap and
simple, and has been found upon trial, as it is said, to afford very
satisfactory results. It consists of a tube four inches long and
an inch and a half in diameter, made of pasteboard, and there is
a@ contrivance at one end by which bodies may be placed across
it ina regular and uniform position. The bodies that are employed
by M. Horner are discs of very thin varnished paper, and
according to the number of these ‘that it is necessary to employ
in order to intercept the light that we are examining, we estimate
its intensity. ;
XI. On Phosphate of Iron By J. Murray, Esq.
(To the Editors of the Annals uf Philosophy.)
GENTLEMEN; Ayr, May 19, 1818.
In reference to the notice of « Native Prussian Blue ” (blue
iron ore, or earthy phosphate of iron), in the Annals of Philo-
sophy for May, I may mention that during my visits to the Isle
ot Man last year, I paid some attention to its interesting mine-
ralogy.
On the farm of Ballatesin, in the parish of Ballaugh, there is
a bed of white shell marl running NE. by E., and S.W. by W.
This marl is white as chaik when dry, and so light as to be super-
natant. Peat, or bog earth rests incumbent on the marl. The
marl is hollow on the surface, and seems to form an independent
basin, the extent of which is not yet ascertained,
About five yards below the surface, various elk horns (the
fossil elk of Ireland) have been found. Those first discovered
were attached to the bones of the skull, and measured 11] feet
from tip to tip. The horns since observed are much fractured.
Different other bones of the skeleton are occasionally met with.
ese all lay in a horizontal position. On minutely examining
the interior of a fragment of one of these horns, I found a consi-
derable portion of the blue earth in question; and on further
search, quantities interspersed through the caked peat earth
meumbent on the marl. The recent fracture is uniformly blue,
feels meagre to the touch, and soils the fingers. It is found in
small lumps, earthy, and in powder. The colour much resem-
bling | common powder blue, or prussian blue of an inferior
description.
T have not yet analyzed this interesting substance, to deter-
mune whether the analysis which considers it to be a compound
* Abridged from Bibliotheque Univereelle, vi, 162.
K 2
148 Scientific Intelligence. [Aveust,
of iron and phosphoric acid be correct; but whether it be so
constituted, or possesses for its proximate parts red oxide of iron
and prussic (hydrocyanic) acid. Its production is easily
accounted for. ‘The peat earth is highly impregnated with red
oxide (peroxide) of iron; this filtermg through the superstrata
comes in contact with the osseous phosphate of lime, and the
phosphate of iron is formed. On the other hand, the prussic
acid may be easily supposed a resulting product of the decom-
posing horn. Carbonate of ammonia, being thus freed, contains
the elemental constituents of prussic acid, and a slight modifica-
tion in the ratio of the proportional quantities would give form
to the hydrocyanic acid, one of the constituents of prussian blue,
the prussiate of iron.
» In this valuable marl are found chips of dints.
I have the honour to be, Gentlemen,
Your most humble servant,
J. Murray.
XII. Analysis of the Eggs of the Pike. By M. Vauquelin.*
A portion of these eggs was washed in a large quantity of
water; the water was evaporated, and a ‘white coagulable
substance was procured, which was completely soluble in caustic
potash, and was precipitated by the infusion of galls and nitric
acid. By drying ,and calcining this substance, its saline con-
tents were separated and their nature ascertained ; the coagu-
lable substance was determined to be albumen, and the salts
were found to be potash, phosphate of potash, muriate of soda,
and phosphate of lime. ‘The water which had been separated
from the coagulum was next examined, and was found to con-
tain both animal and saline matter; a great number of reagents
were employed to ascertain the nature of each; and the result
of the experiments was, that there were two kinds of animal
matter, one of an oily nature, and the other “ an animal sub-
stance having a relation to gelatine.” This it may be presumed
was the same kind of substance which Dr. Bostock found in the
albumen ovi of the common fowl, and which has since been found
in all albuminous fluid. The salts in what may be termed the
serosity of the egg were the muriates of potash, soda, and
ammonia, the phosphates of potash, lime, and magnesia, and
the sulphate of potash. The eggs, likewise, were found to
contain phosphorus. The author observes that there is a very
strong resemblance between the eggs of fish and those of birds
in their composition. There is, however, one circumstance in
which the eggs of the pike differ from birds’ eggs, that the oil
which in the latter is mild, and of an agreeable odour and flavour,
in the former is acrid and extremely nauseous, so as to produce’
vomiting when taken into the stomach. M. Vauquelin observed
the same circumstance with respect to the eggs of the pike that
* Abstracted from Journ. Pharm. iii. 385, (Sept. 1817.)
1818] Scientific Intelligence. 149
Fourcroy and he had noticed in their experiments upon the mil
of the carp, that a large quantity of phosphoric acid was produced
by combustion. It 1s upon the whole more probable that this
phosphoric acid was generated by the union of oxygen with a
portion of the phosphorus which was contained in the substance
of the eggs, than that it was produced merely by the decompo-
sition of any phosphoric salts.
XIII. Notice of the Chevalier Giescke’s Travels in Greenland.*
M. Giescke spent five winters in Greenland, the first at Godt-
Laub (Good Hope) in the latitude of 65°; the three next in the
island of Disko, in the latitude of 70°; and the last at Omenak,
at 73°. The most severe cold which he experienced was about
— 39° Fahrenheit, that at which mercury freezes, and the greatest
heat about 86° Fahrenheit. The whole country is traversed by
an immense mass of ice, divided by deep fissures, that completely
cuts off all communication from one part to the other ; the thick-
ness of the ice is in many parts more than 100 fathoms. The
trees consist merely of a few small and stunted specimens of the
dwarf birch and some species of willows; the only plants that
are employed for food are the Rhodiola rosea, the roots of the
Polygonum viviparum, the flowers and leaves of the Saxifraga
oppositifolia, the Oxalis, the Angelica, and the Cochlearia; there
are also the berries of the Empetrum nigrum, and the Vacci-
nium, which are the only fruits that are found in Greenland.
The Greenlanders seem to belong to the Mongol race ;
their stature is small, and they seldom arrive at a greater age
than 50 years ; the women are nearly as tall and as robust as
the men, and join with them in all their labours and exercises.
Their habitations are all situated near the coast, as the climate
is there less severe, and it is more convenient for fishing, which
is their principal occupation ; they are generally placed in the
recesses of the rocks, and are supported by them; they are
constructed of large masses of micaceous schistus, the crevices
of which are filled with peat, and are lined with moss. Each
hut is about 15 feet square, and is occupied by about 20 indivi-
duals, who lie in it promiscuously. The apertures for the pur-
pose of admitting light are closed with the intestines of the seal
instead of glass ; and the entrance into the huts is a long and
narrow passage which just admits a man to creep in. They are
heated and lighted by a lamp, which is suspended in the middle
of the chamber, and over this they cook the flesh of the seal,
which in the winter is their principal food. The houses are
almost totally without any description of furniture, and are filthy
to a degree which can scarcely be conceived ; all access of
fresh air is carefully excluded, and the heat and stench is abso-
lutely insupportable, except to those who have been inured to
* Abridged from Bibliotkeque Universelle, vii. 133. (Feb. 1818.)
150 Scientific Intelligence. fAueust,
them from infancy. Their only domestic animals are dogs,
which serve as beasts of burden, and are employed by them im
place of horses.
The sea-coast is almost covered with rocks and shoals, and is
without any appearance of vegetation; the part which is not
composed of rock being either bog or marsh. The rocks are,
however, covered with very beautiful lichens and mosses of the
most brilliant colours; and the cascades which fall from the
glaciers between the rocks occasionally form very grand scenes
M. Gieske has paid the most minute attention to the minera-
logy and natural history of Greenland; he has particularly
noticed many remarkable geognostic facts, and has also disco-
vered several new mineral substances. He is at present prepar-
ing to publish an account of his travels both in English and
German ; the work it is said will extend to three large volumes,
and will contain many engravings consisting of views of the
country, and representations of the inhabitants, their utensils,
costume, &c.
XIV. Experiments to determine the Action of Alcohol of are:
Degrees of Strength on the Oil of Bergamot. y M.
Vauquelin.*
It is a common practice with the dealers in perfumes to adul-
terate the oil of bergamot with alcohol; and M. Vauquelin was
induced to make a series of experiments in order to discover the
effects that were produced by the mixture of these two substances,
and thus be enabled to detect the fraud. He found that 100
measures of alcohol dissolved 50 measures of oil, but that there
were several anomalies in the proportions in which smaller
quantities of alcohol dissolved the oil. The general results of
the experiments are; 1. That the oil of bergamot may contain
eight per cent. of alcohol, of the specific gravity of 817, without
its bemg perceptible when mixed with water. 2. That when it
contains a greater quantity of it, the surplus separates, dissolving
about + of its volume of oil. 3. That a small quantity of water
mixed with the alcohol diminishes remarkably its action upon
the oil; since alcohol of specific gravity 880 dissolves only =
of its volume, while pure alcohol dissolves almost 4 its volume.
4. That when we mix alcohol with a volatile oil, a mutual ex-
change takes place between the two fluids, the relation of which
must vary with the purity of the alcohol ; this last dissolves the
oil, whilst the oil absorbs the alcohol. 5. That when we mix
alcohol of specitic gravity ‘847, for example, with oil of berga-
mot, which is °856, the alcohol sinks to the bottom, and the oil
swims upon it; this depends upon’the oil absorbing a part of
the pure alcohol, and thus rendering the remainder more dense,
while it becomes itself more light. 6. That there takes place a
* Abridged from Journ, Pharm. iii. 241, (June, 1817.)
1818.] Scientific Intelligence. 151
kind of decomposition of the water and alcohol by the oil ; from
which it may be suspected, that if we were to mix a small quantity
of diluted alcohol with a large quantity of volatile oil, the water
would be separated, and be precipitated alone to the lower part
of the vessel. Hence we learn that the dealers in perfumes may
introduce eight per cent. of alcohol into them without our being
_ able to detect the fraud by the ordinary means ; but it may be
discovered by the assistance of the spirit hydrometer, as the
density will be diminished by about +1, part.
Sulphuric ether does not act on the oil of bergamot like
alcohol; it unites with it in all proportions, and the fluids do not
afterwards separate.
XV. Analysis of Rice. By M. Vauquelin.*
The object of the author in this analysis was chiefly to ascer-
tain in what respect rice differs from the other cerealea; and
especially to know whether it contains any saccharine matter
proper for the formation of alcohol. A quantity of rice was
pounded and macerated during some time in water ; a transpa-
rent mucilaginous liquor was formed, without taste, that was
neither acid nor alkaline, and was not precipitated by acetate of
lead ; by evaporation an extract was formed that in every respect
resembled gum arabic. By treating this extract with nitric acid,
a strong acid liquor was formed, from which water separated the
phosphate of lime. This solution also contains a quantity of
starch; and the author found that it was by means of the starch
that the phosphate of lime was dissolved in the infusion. He
also found in the same manner that animal jelly rendered a
portion of phosphate of lime soluble. The author then examined ©
the farina of rice, with a view to discover the quantity of ani-
malized matter which was united to it, by distilling it and ascer-
taining the amount of ammonia disengaged ; this was found to
be very inconsiderable ; he afterwards made an experiment for
the purpose of determining at what degree of heat the starch
begins to dissolve in water, which, by means of the test of iodine,
he determined to be 144°5°. (F.)
The conclusions which M. Vauquelin deduces from his expe-
riments are, that rice is a grain essentially amylaceous, which
contains scarcely perceptible traces of gluten and of phosphate
of lime. In this respect it differs from the other cerealea that
serve for the nourishment of men and animals, which contain
a considerable proportion of these substances. He was not able
to detect any saccharine matter in rice, a circumstance which
is considered as remarkable, because in some countries an ardent
spirit, called arrack, is prepared from it. But potatoes also
“afford a spirituous liquor, although they, in like manner, contain
no saccharine matter; from which we must conclude that
alcohol may be formed by something else besides sugar, unless
* Abridged from Journ, Phys, Aug, 1817.
152 Screntific Intelligence. [Aveust,
we suppose that the sugar is so enveloped in the other ingre-
dients that it escapes the ordinary means of detection.
XVI. Analysis of the Kupfernickel. By Prof. Stromeyer.
Professor Stromeyer has been making an analysis of the
kuppernickel of Riegelsdorf, in Hesse, with the following
result :
Arsenite cided sigetaed tiie o Satu chee AR 54°726
Nickel, with a slight admixture of cobalt.. 44-206
DRAM ENC is othe. hia shee. aaa ete RR 00°337
Miers tiaiwid jaiticiata cee ei Rome eke 00°32
page AAT «ike antedattelinis WWM LETS cae .- 00-401
100-000
From this it appears that the essential constituents of kupfer-
nickel are arsenic and nickel. This is further confirmed by an
analysis, by the same chemist, of the nickel ochre, which, in
some cases at least, originates from the spontaneous decompo-
sition of kupfernickel.
Oxide of nickel, with a trace of cobalt.... 37°35
ATSCHIGUS OIE. neste hier Pie ciate aha hela 36°97
W ateniw joieshtee aicld supra’ Sey cei tet ai ar 24°33
Oxide, Gf irenigis aadssli.c Giles. Pig fee, 1:13
Sulphuric iacidia sis c}4 i iwiwa kis Lek Fe « ghendk 0:23
100-00
Hence the former of these minerals is a native alloy of arsenic
and nickel, and the latter is arsenite of nickel.
XVII. On the new Metal Cadmium. By M. Gay-Lussac.*
The new metal resembles tin in its colour, its lustre, its soft-
ness, its ductility, and the sound which it produces when it is
bent. It melts and volatilizes at a temperature a little lower than
zinc. It preserves its splendour in the air; but by heat it is
changed into an orange yellow oxide, which is not volatile, and
which is very easily reduced. This oxide does not colour borax;
it dissolves very readily in acids, and forms colourless salts,
from which it is precipitated white by alkalies. The hydrosul-
huric acid precipitates it yellow, like arsenic. Zinc precipitates ,
itin the metallic state. Its specific gravity at 77° (F.) is 8-635.
The metal was discovered in the autumn of the last year, by
M. Stromeyer, while he was officially examining the apotheca-
ries’ shops at Hanover. M. Hermann, who prepares this oxide
on the great scale for medicinal purposes, having been prohi-
bited from selling it (because the presence of arsenic had been
supposed to have been detected in it) particularly examined it,
and perceived that it contained a new body, which he procured
* Ann. de Chim, et de Phys. viii. 100. (May, 1818.)
1818.J \ Scientific Intelligence. 153.
in a separate state, and sent to M. Stromeyer, begging him
to verify his conjectures. M. Stromeyer soon found that it had
the same properties with the metal which he had just discovered,
to which he gives the name of Cadmium.*
XVIII. Experiments on Manna. By M. Bouillon-la-Grange.+
The principal result that M. Bouillon-la-Grange has obtained
is that manna consists of two substances, that seem to have
distinct properties, and that may be separated from each other.
If manna be digested with alcohol, a part of it is dissolved, an
amber-coloured fluid is obtained, which, by being partially eva-
orated and then cooled, deposits crystals in small needles.
his part of the manna, which 1s soluble in cold alcohol, appears
to be very analogous to sugar. What remains is a whitish-grey
substance, hard, and brittle, upon which cold alcohol has no
action; it may, however, be dissolved in boilmg alcohol, from
which it crystallizes by cooling. This part, when treated with
nitric acid, forms the malic and oxalic acids, and a quantity of
the mucous acid, which is precipitated.
XIX. Experiments on Malic Acid. By MM. Bouillon-ls-
Grange and Vogel.
We are informed that a memoir on the subject was presented
to the Institute in the year 1807; but it appears that the expe-
riments were considered not sufficiently conclusive, and on this
account the authors were induced to reconsider them. We shall
not at present detail them to our readers, but we shall state the
propositions which they deduce from them.
Nitric acid, however weak, forms with sugar an extractive
matter, which unites intimately to the acetic acid, which also
results from the action of nitric acid on sugar. This extractive
matter combines with lime, barytes, alumine, and many of the
metallic oxides, and forms with them compounds, which are
nearly or-totally insoluble in water. It does not decompose the
earthy salts, but it decomposes many of the metallic salts, and
especially those with bases of lead and tin. Sometimes it is
found perfectly white, at other times more or less coloured, as
in the sap of the sycamore, and the birch, and the juice of the
iistect: The juice of apples and of buckthorn contains
uncombined acetic acid ; and a great quantity of this extractive
matter, and the malic acid, which we obtain from these sub-
stances, is a compound of acetic acid and this extract. The
fluids which do not form a precipitate with the acetate of lead
do not contain any of the extract; of this kind are the solutions
of sugar and gum, and linseed mucilage. The extract may be
separated by barytes, and by combining it with acetic acid, the
malic acid may be formed.
* See Annals of Phil. xii. (5.
+ Abstracted from Journ, Pharm, iii. 10, (Jan, 1817.)
} Abstracted from Journ. Pharm, iii. 49, (Feb. 1817.) ,
154 Colonel Beaufoy’s Astronomical, Magnetical,
June 5,
-9,
28,
30,
Magnetical Observations, 1818.
[Aucust,
ArTicLe XVIII. |
Astronomical, Magnetical, and Meteorological Observations.
By Col. Beaufoy, F.R.S.
Bushey Heath, near Stanmore.
Latitude 51° 37/ 42” North,
Longitude west in time 1’ 20°7”,
Astronomical Observations.
1’ 17” Mean Time at Bushey.
14>
14
13
13
14
Immersion of Jupiter’s first
BICERIEE.S/. byaps's vitis eab.ce o's 6
Immersion of Jupiter’s third 5
BEECILILG Sains cick © ce eyecess
Immersion of Jupiter’s first j
Sra leM es aiciars ois" oie p oplawiemicnt AL
Emersion of Jupiter’s first §11
satellite span Ay (UL
8
45
46
18
19
1
3
38
26
47
10
31
44
05
Mean Time at Greenwick,
Mean Time at Bushey,
Mean Time at Greenwich,
Mean Time at Bushey.
Mean Time at Greenwich,
Mean Time at Bushey.
Mean Time at Greenwich,
Variation West.
Morning Qbserv.
Noon Observ,
Evening Obsery.
Month,
. Hour. | Variation. Hour. | Variation. Hour. | Variation,
June | 8h 25'| 240 35’ 59/| 1 25’! 24° 44! 34” Th 30’| 24° 39° 19”
2| 8 35]|24 32 46 1 25) 24 46 24] 7% 30} 24 36 15
31.8 30] 24 33 I1l 1 35 | 24 47 38 7 30) 24 37 14
4| ‘8 30|24 34 14 1 25) 24 47 30| 7 30] 24 37 19
5} 8 30] 24 33 04;— —|— — —]} 7 35] 24 37 58
6| 8 30] 24 32 56 1 10| 24 49 922 7 45|24 40 10
7| 8 30| 24 44 34 1 50/24 53 42 Y 25 | 24 38 45
8| 8 15|;24 34 O1;— —j~- — — 1 35) 24 38 49
9| 8 15| 24 33 48 1 25| 24 44 3%| 1 30) 24 37 33
10; 8 25) 24 36 00 | Nhe 3 Ta hie: ee: Ba q. 25°1 24 936 50
11} 8 35) 24 35 02 1 30] 24 43 45] 7 45] 24 89 46
12) 8 40 | 24 34 15 1 30); 24 44 00; T 30| 24 37 Qi
13 8 40 | 24 36 48 1 20; 24 41 44 1 40) (oe Tao 20
4;);—- —/;— — — 1 20} 24 44 12g 1 35|24 37 40
35) S89 S5/1624 5341.42 1 30; 24 44 45);— —|;— — —
16} 8 30] 24 32 48 1 25) 24 44 50 7 30| 24 40 06
7 8 35) 24 34 56 1 20/24 44 24|— —/|/— — —
18} 8 30|24 34 36 1 25 | 24 45 26 7 35|24 38 55
19} 8 25 |24 32 46] 1 25/24 47 30;— —|— — —
20) 8-20 | 24 338 42) —. —| =. fF: 1 25 | 24 36 44
21 8. 30,1, 84 | 32. 32 1 40 | 24-46 ll 7 10| 24 37 36
29} 8 40] 24 32 51 1 20| 24 43 51 Y 40 024 ST 57
23\| 8; 25°) 24/33. 14 1 30] 24 44 57 4 35|24 37 11
24) § 30) 24 33 32 1] 35|24 43 22) 7 35 | 24 36 26
25; 8 40/124 31 48 1 25 | 24 46 373 7 30| 24 36 56
26) 8 30] 24 31 57} 1 25| 24 44°43} 7 50| 24 39 45
27 8- 25) 94° 31° 50 1 30| 24 44 30; 7 30] 24 38 41
28} 8 25 | 24 32°42 1 25 | 24 44 31 7 25 | 24 39 O85
29; 8 30) 24 34 53 1 45 | 24 45 06 7 35 |24 35 40
30| 8 30/24 34 02 1 15 | 24 45 18 1 35.| 24) Sb 2s
Mean for i
the 8 30| 24 33 4% lk 27) 24 45 11 7 33 | 24 37 40
Month,
-
Tn taking the monthly mean of the observations, those on the
morning and noon of the 7th are rejected, being so much in
excess, for which there was no apparent cause, :
1818.]
and Meteorological Observations,
Meteorological Observations.
Month.| Time. | Barom., | Ther. Hyg.
Jun Inches,
Morn.,..| 29°550 60° | 39°
1 <|Noon .| 29°550 68 26
Even ,...| 29°560 64 33
Morn,...| 29°600 66 38
2 2\Noon....| 29°605 13 26
Even....| 29-600 65 30
Morn, ,,. .| 29°654 62 38
32 |Noon,...| 29-657 72 26
Even....}| 29-680 67 33
Morn,...| 29:733 66 36
42 |Noon....| 29°750 15 22
Even ....| 29-780 65 29
’ Morn....} 29°876 67 A3
Noon... _ — —
Even ....} 29°891 67 31
Morn....} 29-900 64 36
6< |Noon....| 29°885 75 30
Eyen -| 29-885 64 43
Morn....| 29:825 58 50
74 |Noon....| 29-790 13 30
Even....| 29°795 65 33
Morn....| 29°825 64 36
84 |Noon... _ — 21
Even ....| 29-838 66 28
Morn....| 29-837 66 35
94 |Noon....| 29-820 | 72 29
Even ..,.| 29°786 64 31
Morn....| 29-785 66 35
304 |Noon..../ 29-800 | 75 25
Even ....| 29-800 67 34
Morn,.,.}| 29°720 10 34
114 |Noon....| 29-680 | 79 24
Even ....| 29-660 69 35
Morn....| 29°615 val 37
129 |Noon....| 29°615 | 82 | 93
Even....| 29°558 ve! 27
Morn....} 29:510 qt "ao
139 Noon....| 29:503 | 82 | 91
Even ....| 29:485 71 30
Morn....| 29°525 — 57
149 Noon....| 29:55T7 | 70 | 41
Even....| 29-600 66 40
Morn....| 29-625 65 AT
154 |Noon....| 29°603 | 72 | 33.
TAVED ctec'0f _— ae
Morn....| 29°550 63 AT
169 |Noon....| 29°507 | 72 | 35
Even ...| 29-435 66 Al
Morn....] 29°378 64 51
17 |Noon....| 29:300 | 76 | 43
Even....] 29°275 68 59
Morn,...|°29°300 60 42
18) |Noon....| 29-300 71 32
Even,...| 29°310 63 39
Wind, .-
NWbyN
Calm
Feet,
155
Velocity.!Weather.| Six’s.
Fine 549
Cloudy 72
Cloudy
Very fine as
Very fine| 73%
Very fine
Clear : 1%
Clear 15
Clear
Clear : ay
Wh.haze| 76
Clear
Hazy : 55
— 76
Very fine
Very fine f 533
Very fine} 76
Fine
Very fine : 493
Very fine} 752
Clear 5b
Clear :
Clear 133
Clear
Clear ; 55
Clear 13
Clear
Clear ‘ 55
Clear 76
Clear
Clear : —
Very fine} 86
Very fine}
Very hat ad
Fine 83
Cloudy
Very fine ‘ 6
Very fine] 84
Thunder 61
Rain
Fine TI
Fine
Cloudy , sia
Fine 74
Fine ‘ 5%
Cloudy 73
Cloudy
Showery : 60
Cloudy 70%
Rain BA
Fine ‘
Cloudy 12
Cloudy
|
156 Col. Beaufoy’s Meteorological Observations.
Meteorological Observations continued.
Month. | Time.
Morn,...
Noon....
Even ....
Morn....
23¢ |Noon....
Even ...
Morn....
242 |Noon....
Even....
Morn,...
25) Noon,...
.| 29°650
...{ 29°648
..-| 29°500
.| 29°405
Even....
.| 29°336
at Noop....
Even....
Noon....
.| 29°792
Inches,
| 29°370
29-370
.| 29°236
29-195
29°365
29-580
29-550
29-500
29-340
29-285
29°262
29°380
29°457
297445
29°48T
29°5S3
29°613
29°660
29°615
29°583
29°628
29°310
29°393
29°533
29°740
29°782
«« «| 29°823
29°815
.| 29°T80
59°
62
56
56
57
63
57
59
63
59
39°
35
14
49
52
46
wsw
SW byS
ssw
W by
WNW
Ww
Feet,
[Avéusrt,
Barom. | Ther.| Hyg.| Wind. |Velocity.| Weather.|Six’s.
Very fine} 53° ,
Cloudy 654
Rain 51
Fine ‘
Showery| 63
Fine AT
Fine ‘
Sm. rain| 65
Sm. rain
Showery ‘ a
Showery | 66%
Cloudy
Fine ‘ 49
Fine 663
Cloudy
Very fine ‘ a
Fine 69
Very fine
Sm. rain ‘ 55
Fine 13
Fine
Fine ; ie
Cloudy 13%
Very fine
Very fine : aa
Fine 719
Cloudy
Showery {55
Showery| 67
Cloudy
Very fine ‘ oA
Cloudy 13k
Cloudy
Very fine : 553
Very fine). 78
Fine
Rain, by the pluviameter, between noon on the Ist of June
and noon the Ist of July, 0°33 inches.
The quantity that fell
during the same period, on the roof of my observatory, which
is flat, covered with lead, and contains 259 superficial feet,
0-336 inches. Evaporation, between noon the Ist of June and
noon the Ist of July, 6°98 inches.
1818.) ° Mr. Howard’s Meteorological Table. _~ 157
ArTICLE XIX.
METEOROLOGICAL TABLE.
BaRoMETER, THERMOMETER, Hygr. at
1818, |Wind. | Max.| Min.| Med. |Max.|Min.| Med. | 9 a, m, (Rain.
5th Mon. ; ‘5
May 27\N E 30°23 30°13/30°180} 67 | 39 | 53-0
28)N E/30°13)30°09'30'110|] 69 | 44 | 56°5
29|N E|30°13/30-01/30-070] 63 | 41 | 52-0
30|N _E/30-02/29-90/29'960] 65 | 33 | 49°0
31}N W)29°97|29-90|29-935| 74 | 51 | 62°5
June 1{N W/30-00/29:97\29:985| 77 | 57 | 67-0
2; W_ |30:05/30:00/30°025} 80 | 43 | 61°5
3} W_ |30°14)30°05|30:095| 80 | 45 | 62°5 @
AIS E'30°30/30°14/30°220] 82 | 45 | 63°53
5| E |30-33/30-30130:315| 79 | 43 | 61-0
6|IN E)30-33/30°25'30-290] 78 | 45 | 61°5
7\S_ E)30°27|30'18/30:225| 77 | 52 | 645
8S E/30-27/30-23'30-250} 75 | 49 | 62-0
95 E)30-23/30'20|30-215} 75 | 46 | 60-5
10/S E.30-21/30°10/30°155|' 80 | 50 | 65°0
11S __E/30°10/29:98'30°040| 84 | 47 | 65:5 )
12) E /29°98/29'85.29'915| 88 | 51 | 695
13. NW 29°93/29°82)29875] 89 | 58 | 73°5 3
14.N W/30:07|29°93'30-000} 75 | 49 | 62°0 =
15'S W’'30:05|29:92 29-083] 78 | 55 | 665 ss
16'S _W/29'9%29'75 29°835|.78 | 59 | 68°5
17'S W |29°70)29-67|29°685| 74 | 54 | 640 | * 6
18.N W 29°79)29°09|29'740| 75 | 49 | 62:0 50 | —10
19/S W (29°79)29'53/29°660 72 | 52 | 62°0 45 2
20|S . W/30-00/29-60)29-800| 72 | 46 | 59:0 AT 1
21|S W)30:00/29:75|29°875| 71 | 56 | 63°5 43 6
22/S W/29°76/29-64/29:'700] 71 | 50 | 60°5 62 25
23|N W/29'87|29-76|29-820| 71 | 53 | 62-0 44
24)N W)30:09|29°77/29°930| 74 | 52 | 63-0 47 | —
25|S W/30:09/30°02/30'055| 79 | 56 | 67°5 Sp Aas 4
| a | en | cen | ee |
30°33 29°53}29'998 89 | 33 62°36 48 | 0°43
——————
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 resultiis inciuded in the next following observation,
158 Mr. Howard’s Meteorological Journal. [Aueusr,
REMARKS, -
Sixth Month.—6. Since this period came in, the weather has afforded little
variety. The days have been serene, wita breezes, which commonly increased
with the temperature, and died away at sun-set: the nights nearly calm, with dew,
and a peculiarly clear, but not high-coloured twilight. Thunder clouds have shown
themselves at intervals in the horizon; and to-day there are large plumose Cirrz.
8. My brother observed, about nine, p.m. a bright, blue meteor descending from the
zenith tothe NW. 10. After sun-set, some beautiful diverging shadows on a pure,
dilute, carmine tintin the NW. 11. Thunder clouds about. 12, A thunder group
in the N and NW: the Cirrostratus for a short time assumed the form of the Cyma,
and several discharges were heard while the Nimbi expanded their crowns within
view : after this, it lightened insome clouds to the SE, 13. Cumuli, mingled with
haze and Cirri, were followed in London by a smart thunder shower; while at
Tottenham there fell but little rain: a lunar corona ensued. 14. A little rain,
a,m.: alarge, faint lunarhalo. 15. A few drops at evening. 16. Cloudy: a
strong breeze. 17. A light gale, with a rainy sound, and much cloud; but the
showers proved scanty. 18. Much cloud, chiefly Cumulostratus: after some light
showers, and appearances of rain and thunder to the southward, the twilight
cleared up orange. 19,20. Windy, cloudy: light showers; Cumulus, Cirrocumu- -
Tus. 21. Cumulus, with the lighter [modification above, increased to obscurity z
wind throngh the day, and small rain, evening. 22, Windy, cloudy morning: this
day more decidedly showery. At 11 p,m, a shooting star descended to the SE.
23, 24. More calm, with summer clouds in various modifications. 25. A very
slight rain, a. m. followed by fine blue sky, and various clouds carried by a strong
breeze.
RESULTS. |
Winds in the fore part light and Easterly, in the latter part Westerly and stronger,
Barometer : Greatest height......-..ccsecsceceseccsesecesss 30°33 inches,,
TiGHSt Te acdin nae Re nels ehaleses a,c alia ats ¢alatpire ciere ites tame
Mean or themperigt) 15 0. cclees ss cence ake rcleeaneerguls
Thermometer: Greatest height........sccceescecrecseecescceee 397
TASH Goo hole aie dale o Pela slcelat eaelaneis sb ianelaialstin~ (oer
Mean of the period (at the Laboratory) ........ 62°36
Mean of the Hygrometer (the latter week) .....0.seeeeeeseeeee 48
Evaporation (a few days estimated). ,...++esesereserrerereeees 4°50 inches.
Ee ee ear aee abate atoletalcis o enie aia dle e's oles ieielnaitiainje'sn fear MUCNESs
The clear hot sunshine of the greatest part of this period had the effect of esta-
blishing the summer in our climate in a manner to which we haye long been
unaccustomed. The deeper green of the foliage and the richer colour of many
flowers in particular presented a striking contrast to their appearance during the
last two seasons; while the soil, parched and cracked over the whole surface of
our loamy meadows, bore ample testimony to the continued receptive power of
the dry atmosphere. Yet the turf (to use a familiar phrase) did not burn, proba-
bly in consequence of the supply of moisture still left at a certain depth in the soil.
1818.] Mr. Howard’s Meteorological Table. 159
METEOROLOGICAL TABLE.
i
BaRroMeETER. THERMOMETER. |Hygr, at
1818, |Wind.| Max. may Med, | Max, Min. | Med, | 9 a.m. {Rain.
{Pawnee -_
6th Mo. |
June 26/8 W/{|30-05|29°9530-000) 79 | 49 | 640 AT
97\S E/29'95 29°67 |29°S10| 84 | 55 | 69°5 43° | —
9815 W/30-17|29°'75|29°960| 72 | 52 | 62:0 4A 20
29} Var. |30°26|30'17'30°215| 81 | 51 | 66:0 43 |—
30IN W130-26/30°15'30°205| 84] 52 1680) 43 | —
7th Mo. |
July 1)N E)30°15)30-02 30°085)
-2) Var. |30°22/30°10 30°160| 73 | 44 | 58°5
3IN W/)30°22\30°06 30°140) 79 | 57 | 68:0 45 &
Al N_ |30°06!30°04'30:050| 77 | 52 | 64°5
5\N__E/30°10/30'04.30-070) 79 | 51 | 65:0 46
BIS E130-10 30°00/30°050) 84 | 52 68:0 45
71S E}30°00/29' 80 29:900, 81 | 56 | 685
SIN W({30°11/29°80!29:955| 74 | 50 | 62:0 46
QIN W/30°11)30°10/30°105| 78 | 53 | 65-5 45
10} Var. |30°10/29°95|30°025| 76 | 55 | 65°5 42
11\S W/\|29:95|29°76'29°855| 79 | 50 | 64°5 42 33D
12IN W/{29'85/29:76|29°805| 74 | 57 | 65°5 70 i
13} N_ |30°20/29°85|30°025) 77 | 52 | 645 52
14\N W130°32/30'20\30:260) 83 | 57 | 70°0 52.
15) Var. |30°32/30°28'30°300| 86 | 53 | 69°5 47
16\N £/30°28/30'18 30°230| 88 | 62 | 75:0 45
17| E 1|30:20!30'0930°145| 82 | 52 | 67-0 53 |—'O
18|S E|30-09|29°91 30°000| 84 | 57 | 70°5 50
19|N W/29:95|29°88 29°915| 85 | 59 | 72-0 50
20} Var. |29°95|29'92 29 935| 76 | 52 | 640 55
21|N W130:05|29:95 30:000! 80 | 56 | 68-0 45
2921S W/30'13/30°'05 30°090| 84 | 55 | 69°5 45
23/8 B/30"13)29°83 29:980| 83 | 60 | 71°5 AT
2415S E/29-83/29°80 29°815| 93 | 61 | 77:0 40 9
'
ae | eet | | ce
30°32|29°67'30°037| 93 | 44 | 67-24 47 {0°63
REMARKS,
Sixth Month.—27. It is said to have been misty early. Someremarkable, rapid
changes in the electrical state of the clouds took place, the wind being brisk,
veering from SE to SW. Cirri, passing to Cirrocumulus and Cirrostratus, grouped
like the ribs of a vessel, on a kind of keel presenting downwards; very dense
and magnificent, With these were mingled the rudiments of Nimdi, one or two of
which formed in sight, and probably discharged to the NE of us: a few drops fell,
and there were distant thunder storms in different directions at night. 28. Some
fine rain, a.m.: several short, heavy showers about noon: inosculation, and gray
sky, evening. 29,30. Fine, with large Cirriabove Cumuli: some drops of rain.
Seventh Month.—A fine display of Cirrocumulus, with a specimen of the Cirro-
stratus resembling the grain of wood: also large plumose Cirri, p.m.: Cumulo-
160: Mr. Howard’s Meteorological Journal, [Aucusr, 1818, *
stratus, and a few drops, evening. 2, 3. Exhibitions of the Jighter modifications
variously interchanging and mingling, succeeded by Cumulostratus. 4. Windy
morning, and overcast with Cumulostratus: a fine day: twilight coloured, with
diverging shadows. 5, Very fiue day: Cirrocumulus aboye Cumu/us producing
beautiful clouds by inosculation. 6. At three this morning, in the NE, a most
extensive orange twilight, in the form of a pyramid, resting on a base of iow
purple haze, occasioned by dew in that quarter. A fine day ensued, with a
breeze, and Cumuli casting shadows in a somewhat hazy air. 7. The shadows
radiating downward from clouds continue, perhaps occasioned by fine dust foat-~
ing. I observed, in passing Hounslow Heath, two whirlwinds, carrying the dust
in anarrow, perpendicular vortex to a great heightin the air, from wlience it per-
ceptibly showered down again. 8. Cumulostratus, after a clear morning: strong ~
breeze avd much cloud, with a few drops. 9. Clear morning, with Cumulus,
Cirrus, and a breeze. About seven, p. m., setting out to return from London, £
saw, inthe NW, aremarkably Jarge Cirrus, composed mostly of straight, diverg-
ing fibres, extended towards the SW ; and which, when I’got home, had passed to
Cirrostratus. In this cloud (as it appears) my family at the same time observed a
coloured solar halo with two rather indistinct parhelia, the whole of which had
escaped my notice in coming out of town. They described the havo as so large,
that a considerable portion of the circle, if continued, would have been below the
horizon; and the parhelia as situated, the one directly above the sun (which was
somewhat obscured), the other tothe N of it, and both in the circle: the parhelion
to the S (if there were one) was behind some houses ; and the whole appe.rance
had considerably gone off before they could get to view this side of it. Tue phe-
nomena were witnessed by several other persons; and the halo, 1 find, was seen
likewise at Hertford. 10, A few large drops between six and seven, a.m,:
close Cumulostratus prevailed afterwards. 11, Large Cérri, passing to the form of
the Nimbus, mingled with Cirrocumulus and Cirrostratus. In the ey: ning an exten-
sive obscurity in the W and SW, fronted by dense Cirrostrati: afresh, turfy smell
came with the wind, and at length, at half-past 10, it began to rain steadily with
us. 12. Wet morning: fine day afterwards. 13, 14. Fine, with Cumuli, &c.
dew, and orange twilight. 15, A Stratus last night: thunder-clouds about: the
moon bright goid colour, crossed by fine streaks of Cirrostratus. 16, Themoon
paler amidst hazy Cirrus and Cirrostratus, &c, in SE. 17. Cloudy morning: light
shower, then fine with Cirrus and Cirrocumulus. 18. Thunder cloudy, p.m.:
Nimbi, &c. grouped inthe N. 19, Wind, SE; thundercame within heariig to the
NW, p.m.: temp. 85°: hygrometer, 30°: not a drop of rain here, and wind NW
after it. 20. Thunder groups, and rain visible to northward : fair with us: clouds
red at sun-set. 21. Wind W, a.m, Cirrocumulus, chiefly in strips from N to S;
then Cumulostratus, &c. A very variously compounded and coloured sky during
twilight. 22. Fleecy Cumuli, &c. a.m. 23. Serene, with Cirrus, and fine breeze.
24. Cirrus and Cirrvcumulus proceeding to electrical formations: strong breeze
and slight solar halo; p. m. after the maximum of temp. was over, Niméi, with
thunder and lightning, approached from the south. The clouds at sun-set showed
very rich crimson lake and orange tints; and we bad showers, withahollow wind,
and lightning, till past midnight,
RESULTS,
Winds light and Variable.
Barometer: Greatest height 0... cscs ceccencceccessvenecees « SU'S2 INCHES,
TE CHBby\dsidisic'e aisidhats/oistehfe, sociale cackeiontesaaes «no 1en
Mean‘of the Period xc. ce sccmeecnterdateicta en suterearee SOOom
Thermometer: Greatest height ............... PSC ARAES ORR Geo
Least ...... wine =. ofeie'e'e'ulejas sss E deleivieieiwumalsiainctesint Se
Mean of the period (at the Laboratory) ........ 67°24
ANNALS
OF
PHILOSOPHY.
SEPTEMBER, 1818.
ArtTicLe I,
Biographical Notice of M. Deodat de Dolomieu.
DEODAT DE DOLOMIEU, of a noble and opulent family,
was born at Grenoble on June 24, 1750. Being destined from
his childhood to become a member of the military ecclesiastical
Order of Malta, he was entered in early youth on board one of
their galleys. While in this situation, a quarrel arose between.
him and one of his young companions, which terminated in a
duel of fatal consequence to his adversary. The unfortunate
result of this wanton violation of a wise and fundamental law of
the Order occasioned the sentence of death to be passed upon
him ; and it was not till after an imprisonment of nine mon hs
that the conditional pardon which he had obtained from the
Grand Master was finally confirmed by the Pope. On his
liberation he repaired to France, and joined the regiment of
Carbineers, in which he had been appointed to a commission
some years before. It was at Metz, where the regiment was
stationed, that he first became acquainted with the Duke de la
Rochefoucault ; an intimate and unreserved friendship soon took
place between them ; and it is probable that the attachment to
science, by which this nobleman was distinguished, contributed,
im a considerable degree, to direct the energies of the ardent
mind of Dolomieu to similar pursuits. By attendance on the
lectures of M. Thirion, a physician of Metz, he acquired the
rudiments of chemistry and of natural history ; and his spirited
and successful endeavours in stopping the progress of a fire
which threatened the destruction of one of the military hospitals,
Vor. XII. N° III, L
162 Biographical Notice of [Sepr.
were rewarded by the notice and personal friendship of
M. Thirion.
His earliest publications were translations into Italian of Berg-
man’s Treatise on Volcanic Substances, and of Cronstedt’s
Mineralogy, to each of which works he added notes. The
reputation acquired by these, and by some papers which
appeared in, the Journal de Physique, aided by the good offices
of his friend de Rochefoucault, obtained for him the unexpected
honour of corresponding member of the Academy of Sciences.
Deeply affected by the distinction conferred by this learned
body, he was the more willingly led to regard as a duty that
devotion of himself to the service of science which was now
become his ruling passion. In pursuance of this resolution, at
the age of 26, he resigned his commission in the Carbineers,
retaining, however, his connexion with the Order of Malta, in
which he rose, in process of time, to the rank of Commandeur,
and entered on a laborious but interesting course of mineralo-
gical study.
He first established himself in Sicily, for the purpose of
examining on the spot the geological connexion of Etna with
the non-volcanic part of the island, of investigating the
distinctive characters, if such exist, by which the acknowledged
products of voleanos may be separated from the class of trap.
rocks, and of resolving many important inquiries relative to the
proximate causes of volcanic eruptions, the degree of heat
required to maintain the fluidity of lava, and the materials of
which these destructive torrents are composed.
From Sicily he passed into Italy, and examined repeatedly,
and with profound attention, not only Vesuvius, but also the
numerous extinct volcanos which occupy a considerable portion
both of the coast and of the interior of the country between
Rome and Naples. These craters, some of which still pour out
sulphureous and mephitic exhalations, and hence have formed
the scene of many a poetical tale and superstitious legend from
the days of the Cumean Sibyl and of Virgil to the present time,
furnished to the philosophical spirit of Dolomieu many rich
accessions of fact and of theory. At Naples he commenced an
acquaintance with Sir W. Hamilton, the British Embassador,
which similarity of pursuits soon ripened into intimacy.
The Lipari Islands were the next object of his researches : he
examined them with great attention, and made them the subject
of a separate work, entitled “ Voyage aua Iles de Lipari,” which
was published in 1783.
The destructive earthquakes which desolated Calabria in the
same year excited, as might have been expected, in an especial
degree, the notice of Dolomieu. Repairing to the scene of ruin,
he examined, with the most lively interest, the effects produced
by this event on the face of the country, ascertained that the
whole tract was covered by calcareous strata, without the smallest
1818.) M. Deodat de Dolomieu. 163
appearance of volcanic matter, either ancient or recent; and
hence deduced some general principles on the nature and cause
of earthquakes.
Sir W. Hamilton having im 1785 taken a slight survey of the
five islands known by the general name of Ponza (Ponti insulz
of Pliny), which, with the islands Ischia and Procida, form an
interrupted chain in front of the gulfs of Gaeta and Terracina,
and having observed in them many interesting geological
phenomena, suggested a more complete examination of them to
his friend Dolomieu. He accordingly visited them in the spring
of 1786, and brought back with him an abundant coilection of
specimens, and many observations of great importance to the
general history of volcanos. These observations form the sub-
ject of his next publication, entitled ‘ Memoires sur les Iles
Ponces,” 8vo. which made its appearance in the year 1788. In
the preface to this work he states, that he had long contem-
plated a detailed history of Etna, the largest, and loftiest, and
most important active volcano which is readily accessible to
Europeans ; but that the encroachments upon his time, arising
from monastic disputes and the necessity of adjusting petty
interests, and of humiliating his adversaries, had reduced him
to be merely a collector of individual facis for the use of others.
From this complaint, which is made with some asperity, we may
.. conclude that he took a warm and active share in the intrigues
and dissensions which agitated the Order of which he was a
member, and that the foundation was here laid of those resent-
ments from which he suffered so severely some years after-
wards.
On the breaking out of the French revolution, he returned to
his native country; and, following the impulse alike of his feel-
ings and of his friendship, arranged himself, togetlier with the
Duke de la Rochefoucault, among the partisans of reform. His
conduct on this occasion appears to have been perfectly disin-
terested, for he occupied no office either of honour or profit, and
appears, during his residence at Paris in the first years of the
revolution, to have busied himself chiefly in the pursuit of his
favourite study, and in the publication of a few papers on subjects
intimately connected with it. The bloody fanaticism, following
close on the steps of the revolution, which swept off so large a
proportion of the public talent and virtue of France, although it
spared the person of Dolomieu, inflicted on him the irreparable
loss of his most intimate friend La Rochefoucault, who was bar-
barously murdered by a mob of assassins in the presence of his
mother, his wife, and his friend. During the remainder of that
period, emphatically called the reign of terror, proscribed, and
making his escape from one asylum to another, he nevertheless
found leisure to compose and publish two memoirs, one on the
figures presented by the indurated marly slates of Florence, and
the other on the physical constitution of Egypt.
Bee
164 Biographical Notice of (Serr.
The fury of the revolutionary storm was now for the most part
overblown, and, among other encouragements offered to science
by the new government, the Ecole des Mines and the National
Institute were founded. The merits of Dolomieu obtained for
him a seat among the members of the Institute, and he enriched
the Journal des Mines with several interesting papers, among
which may be particularly distinguished his history of the species
beryl, intended as a model of the manner in which the history
of minerals ought to be drawn up ; and his memoirs on the heat
of lava, and on leucite, in which he expounds his opinions on some
of the principal questions relating to volcanos.
He now undertook a new journey to Switzerland and the south
of France, and renewed his former acquaintance with Saussure ;
when the illustrious veteran formally devolved upon him the
office of completing the survey of the Alps, which his own
infirmities compelled him at length to relinquish, and of deduc-
Ing from the multitude of important facts, the joint product of
their several laborious journeys, some fundamental axioms in the
science of geology. The extinct voleanos of Auvergne also
attracted the special notice of Dolomieu during this excursion -
being less encumbered by ejected matter than either the active
or quiescent volcanos of Sicily and Italy, their connexions with
the regular strata are much more easily traced, and many parti-
culars of the very first consequence in their history, which else-
where are the indirect result of dubious observation, offer
themselves in full view to the student of Auvergne.
After an interval of six months thus employed, he returned to
Paris, laid before the Institute a sketch of his labours, and made
the commencement of a very extensive work on mineralogy,
which he had long meditated, and which, founded on researches
so extensive and so accurate, must of necessity have added
greatly to our knowledge of volcanic rocks, as well as to the
science in general.
Unfortunately for Dolomieu himself and for the public, the
prosecution of this great design was interrupted by the offer of
a situation in the expedition then preparing by Bonaparte for the
conquest and colonization of Egypt. With the military rank of
General, but probably with no other objects in view than those
of science, in an evil hour he quitted the shores of France. The
first blow struck by this great armament was the conquest of
Malta; and in the arrangement of the articles of its surrender,
Dolomieu was unwisely induced, by the joint persuasions it is
said of the Order and of the French commander, to take a prin-
cipal share. Bound by ties of allegiance to the sovereign
authorities on each side, it was manifestly his duty not to inter-
fere ; and, involved as he had been in the party disputes of the
Knights of Malta, there could be no doubt that his interference,
even if really impartial, would render him extremely obvious both
to wilful misrepresentation and to involuntary misunderstanding.
1818.] M. Deodat de Dolomieu. 165
From Malta he accompanied the expedition to Egypt, and
proceeded up the valley of the Nile as far as Cairo, from which
place he meditated further excursions in pursuit of his favourite
objects. His health, however, soon became seriously deranged,
and he was obliged to seek for means of returning to Europe.
Embarking at Alexandria, after a stermy passage, in which he
narrowly escaped shipwreck, the vessel was obliged to take
shelter in the port of Taranto. The day after their arrival, one
of the sailors died of the plague, and of course the remainder,
assengers as well as seamen, were placed in close custody.
he Neapolitan territory was at this time in the crisis of revolu-
tionary civil war, the one party being supported by the French,
the other by the British and their allies : as each party obtained
the temporary ascendency, Dolomieu and his companions ran
the risk of being massacred, or were treated with high distinc-
tion. The French army being obliged to retreat from the south
of Italy, the triumph of the royalists became confirmed, and
Dolomieu, together with Cordier, General Dumas, and some
other Frenchmen of distinction, were conveyed prisoners to
Sicily. His companions being simply prisoners of war, were
treated accordingly ; but Dolomieu, by his conduct at Malta
having subjected himself to the charge of a violation of alle-
giance towards the Order, of which the King of Naples was the
acknowledged protector, was immediately separated from his
friends, and placed in rigorous confinement, the severity of his
treatment being probably aggravated by party animosity. Legal
proceedings against him, if they were ever really contemplated, ~
were suspended by the prompt interference in his favour of many
distinguished persons, who nobly postponed on this occasion the
gratification of political feeling in favour of their regard for
science. The Danish government, M. D’Azara, the King of
Spain, Sir Wm.-Hamilton, and Sir Joseph Banks, made appli-
cations in his behalf, which, though not successful in obtaiming *
his liberation, at least prevented the last extremity. At length
the battle of Marengo was fought, which again laid Italy at the
feet of France ; and the first article in the terms imposed by the
conqueror on Naples was the restoration of Dolomieu to his
country and to science. In the mean time his philosophical
associates at Paris had not been unmindful of their colleague,
they having elected him to the Professor’s chair, vacant by the
death of Daubenton. His return to Paris was hailed with
delight by his relations, his friends, and his colleagues ; and he
entered on the duties of his office by the delivery of a short
course of lectures on the general principles of mineralogy. For
the restoration of his health, and in furtherance of his professional
pursuits, he now undertook another journey to Switzerland, in
the course of which he again reviewed and corrected his obser-
vations on the spots where they were originally made. ‘Tearing
himself at length, and with reluctance, from Ais beloved moun-
166 Biographical Notice of (Serr.
tains, as he was accustomed to call them, he returned, through
his native town, to Chateauneuf, near Lyons, the residence of
his brother-in-law, M.de Drée ; and here, while enjoying the
soothing attentions of friends and relations, and meditating
further exertions in pursuance of his favourite science, he was
attacked by a mortal disease, of which he died in the 53d year
of his age.
From a careful perusal of the works of Dolomieu, especially
his later ones, the following appear to be the results of his obser-
vations, and the bases of his geological system.
It appears highly probable from geometrical considerations,
and from the theory of central forces, that the earth at the time
when it received its spheroidical shape was in a state of fluidity.
This fluidity was probably neither the result of igneous fusion
nor of aqueous solution, but of the intermixture of a substance,
or substances, with the earthy particles, fusible, like sulphur, at
a moderate heat, capable of entering into more rapid combus-
tion when exposed to the air, decomposing water, and involving
the gas thus produced so as to enter into strong effervescence
when the superincumbent pressure does not exceed a given
quantity.
- The surface of this fluid by the action of the air on the com-
bustible ingredient which occasioned its fluidity, would at length
become consolidated, and would envelope the whole spheroid
with a shell of less specific gravity than the fluid part, and,
therefore, floating securely on its surface; this latter essential
condition being rendered éxtremely probable from the well-
known fact that the mean specific gravity of the globe is consi-
derably greater than that of any natural rock hitherto known.
The interposition of this solid shell of stony matter, a bad
conductor of heat, between the liquid and the gaseous portions
of the globe, would enable the aqueous and other easily conden-
sible vapours to separate themselves from the permanently elastic
gases, and thus the matter of the globe would be arranged in
four concentric spheroids according to their respective gravities ;
namely, the liquid central portion, the solid stony, the liquid
aqueous, and the permanently elastic. As the water penetrated
through the stony portion to the nearest fluid part, it would be
gradually decomposed, the consolidation would proceed down-
wards, the newly consolidated part would enlarge in bulk, and
thus, aided by the elastic expansion of the hydrogenous base of
the decomposed water, would occasion rifts of greater or less
magnitude in the supermcumbent mass. Some of the larger of
these rifts would open a free communication between the ocean
and the fluid central mass, a torrent of water would rush down,
and the effervescence occasioned by its decomposition would
produce the first submarine volcanos. The lava thus ejected
would in time raise the mouth of the volcano above the surface
of the water, when it would either become quiescent, or, if
2 .
\
1818.] M. Deodat de Dolomieu. 167
supplied laterally with a sufficient quantity of water, would
assume the character of a proper volcano, or burning mountain.
The secondary rocks, 1.e. all those which either themselves
contain organic remains, or are associated with those which do,
were deposited from solution or suspension in water. By the
deposition of these, and the increase by consolidation of the
primitive rocks, the thickness of the mass incumbent above the
central fluid is continually creasing ; and those causes which
anciently broke through the solid crust of the globe are now
rarely able to produce the same effect; hence the greater mag-
nitude and frequency of volcanic eruptions in the earliest ages
of the earth; for the same reason the elevation of large, moun-
taimous, or continental tracts above the general level no longer
takes place ; and thus the surface of the globe has become a
safe and proper habitation for man and other animals. If the
land animals were created as early as possible, that is, while the
great changes of the earth’s surface above-mentioned were still
m progress, many of the most ancient traditions of deluges and
other catastrophes may be founded on fact.
The fluidity of the central part of the globe, and its connexion
with the active volcanos, affords a plausible theory of earth-
quakes, and particularly accounts for the propagation of the
shock, with diminishing intensity, to great distances.
The crystals of hornblende, ‘of felspar, &c. which occur so
abundantly in most lavas are, according to this theory, not those
component ingredients of rocks which have resisted the heat
while the other substances associated with them have been
melted ; nor are they the result of the slow cooling of a vitreous
mass, but are produced by crystallization in the central fluid,
and are accumulated, on account of their inferior specific gravity,
about its surface, together with the peculiar inflammable matter
in which they float, whence they are disengaged during volcanic
eruptions.
ARTICLE II. °
An Account of some Basaltic Columns at Pouck Hill, Stafford-
shire, with Prehnite, Zeolite, and Barytes. By J. Finch, Esq.
(To the Editors of the Annals of Philosophy.)
GENTLEMEN, Birmingham, June 1, 1818.
Havine perused, in the Geological Transactions, a valuable
paper, written by Arthur Aikin, Esq. upon the greenstone
occurrmg at Birch-hill colliery, near Walsall, I was induced to
visit that spot. Having collected various specimens from the
mouth of the pit, I observed that the roads were repaired with a
168 Mr. Finch’s Account of some Basaltic Columns (Serv.
different species of trap from that which I had just procured ;
and on inquiring whence it came, I was directed to Pouck Hill,
where a quarry has been worked many years. This hill is
situated one mile and a half north west from Walsall, at a short
distance from Bentley Hall, which is noted in history as a place
of concealment for Charles Il. The estate belongs to Viscount
Anson. On the north east it adjoins Birch-hill colliery, to which
the ground descends by a gentle slope, and at the bottom a
small stream of water forms a boundary between them. The
distance from one hill to the other does not exceed half a mile.
By barometrical measurement, the highest part of the hill is
60 feet above the level of the colliery, and constitutes a part of
the formation of trap, noticed by Mr. Aikin as forming an
elevated ridge, which crosses that place. The basalt extends
without any interruption from one to the other. It is about 30
feet lower than Bentley Hill, which is the highest land in the
vicinity, and consists of gravel overlying the coal formation.
The extent of the trap may be estimated at nearly a mile in
length. It varies extremely in breadth, from half a mile to 30
or 40 yards, which is the breadth at Birch-hill colliery. Pouck
Hill may be regarded as situated near its centre. The opening
of the quarry at this place has exposed to view some fine basaltic
columns ; many of them are four or five feet indiameter. After
their crystallization on this large scale, they appear to have been
subject to fissures, dividing them longitudinally ; but the original
hexagon can still be distinctly traced. Their length is various,
some of the articulations being very short, and others extending .
to five or six feet. The direction of some is singularly waved,
whilst others are straight; and from their lying in an almost
horizontal position, they resemble at a distance the massy
trunks of trees piled one upon another. Some of the basalt has
attached to it a small incrustation of carbonate of lime in irre-
gular spots. The trap of which this hill is composed is exactly
similar to that of the Rowley Hills; of which an account is given
by Dr. Thomson in the Annals of Philosophy for Sept. 1816.
Those hills are at the distance of 10 miles, and no connexion
can be traced between them.
Near the summit of Pouck Hill is a farm house, to supply
which with water a well about 16 yards deep has been sunk in
the rock, the lowest pump tree resting on a basaltic column.
When the Birch-hill colliery was worked four years ago, the
steam engine, employed to keep the mine free from water,
drained this well, although at half a mile distance. The same
effect was lately produced by cutting a deep trench on the oppo-
site side of the hill beyond the boundary of the basalt. These
two circumstances seem to prove, that this basalt is a superin-
cumbent formation covering the coal. The stream already
mentioned as separating Pouck Hill from the colliery, has worn
itself a channel four feet deep; here the coal strata rise within a
1818.] with Prehnite, Zeolite, and Barytes. 149
foot of the surface, and are covered by the trap in the uncon-
formable manner usually ascribed to it. ;
The columns at the top of the hill dip at an angle of about 30
degrees in two directions, A, B; those on the north dipping
south, and vice versa; this appearance is caused by a fault, C,
which crosses the centre of the hill from east to west. (See
Plate LXXXIII.) This vem, or fault, is about five feet in
thickness, including what appears like a wall on each side of
one foot thick, which can be separated from the centre without
any difficulty. This fault is as wide at the bottom as at the top,
and its direction is exactly vertical. It consists of basalt or trap
in such a state of decomposition that it cannot be ascertained
whether it is exactly similar to the basalt forming the hill. It
contains the followmg minerals :
Radiated zeolite, or mesotype of Hatiy: occurs abundantly in
nodular concretions. In the walls it forms thin veins, which
penetrate the whole of the mass. Some of the specimens have
considerable beauty. Occasionally the zeolite assumes the form
of acicular four-sided prisms radiating from a centre.
Prehnite.—This mineral has not been found before in England.
It occurs in massy, distinct concretions, rather abundantly, near
the surface of the fault, imbedded in sulphate of barytes, and
more rarely attached to the zeolite. Its colours are greyish
white, greyish green, and greenish white. Its hardness very
considerable.
Sulphate of barytes occurs both crystallized and in a loose
state resembling sand, and constitutes the major part of the top
of the fault.
I wish to acknowledge my obligation to the Rev. James
Yates, of Birmingham, for his assistance in arranging the
materials for this paper, for which purpose he has visited the
spot. I have the honour to be, Gentlemen,
Your very obedient servant,
Joun Fincu,
ArticLe III.
Some Remarks on the Climate and Situation of Nice, with
‘Observations on the Temperature and Weather taken in the
Winter of 1816 and Spring of 1817. By a Correspondent.
(To Dr. Thomson.)
SIR, London, 1818.
Dunriné a residence of some months last year at Nice, in a
climate so superior to our own, it was an object of some interest
to myself and party to make daily observations on the weather
and temperature, with a view of comparing them with those
170 Remarks on the Climate, Situation, and [Sepr.
which we received from time to time from our friends in England.
Since my return home | thought it might be an object of suffi-
cient utility, in some respects, to be worthy of a little time and
trouble, to put my observations into some kind of order, by
arranging those of the temperature taken at Nice and in
England * together on a common synoptical scale, by which a
comparison could be more readily made between the two
climates in respect of the changeableness and difference of
temperature. I regret much that I was not furnished with a
barometer, that I might have added observations with that
instrument also into my table.
The latitude of Nice is about 431 degrees north, or eight
degrees south of London, and 73 degrees east of the same.
The city, with its suburbs, is situated in, or rather surrounded
by a rich plain, which may be about a mile and a half from east
to west, and about two miles from north to the sea shore ; it is
bounded by a range of hills, which, beginning to the south east
at the distance of about a quarter of a mile from the town, are
continued as far round as the south west of various forms and
gradations ; and, like the successive benches in an amphitheatre,
rise one above another until the snowy chain of the maritime
Alps, about 8,600 or 10,000 feet high, appears like the boundary
wall to the whole at a distance of about 25 or 30.miles. The
city is situated near the shore, which immediately faces the
south; and the river Paglion, which takes its rise among the
neighbouring mountains, after flowing through the plain, enters
the sea near the city walls. The sea is remarkable for the beau-
tiful blue colour it generally exhibits, probably arising partly
from the absence of tides, by which its waters, being so little
disturbed, become highly transparent. Afterrain, however, the
limestone washings from the neighbouring mountains tinge its
waters to a considerable distance off the mouths of the rivers,
which sometimes has a curious appearance. The deep blue
colour of this sea may also be owing to its depth, which 1s very
considerable off this coast; according to the measurement of
Saussure taken about half a league off the Cape, between the
ports of Nice and Villefranche, the depth was found to be 1,800
feet ; it might also be observed by the great length of line used
by the coral fishers who ply off this shore. Although little or no
tide is perceptible in this sea, a southerly wind, or the approach
of one, raises the ordinary level of the water some feet more or
less upon this shore, and sometimes produces a very consider-
able surf. The sea breezes usually prevailed from about nine or
ten, a. m. to four or five o’clock in the afternoon ; and that was
generally the case even when the upper current of wind came in
quite a different direction. I remarked on one excursion to the
# The observations of the temperature in England which I have used in my
scale are those of Luke Howard, as published in the Annals,
1818.] Temperature of Nice. 17]
summit of Mont Coa, about four miles north of Nice, that the
sea breeze, which was felt so pleasant in the valley, did not
prevail at that elevated station, about 2,000 feet. I occasionally
observed, by the motion of the clouds, that the mistrale, or bise,
(a north east wind so well known in Provence)* was passing
over our heads, whilst the mild breeze from the sea was blowing
upon us.
The sirocco, or south east wind, sometimes came on about
sun-set in a brisk breeze, but at the same time with a mildness
which at first quite surprized me; it was by no means relaxing,
but very agreeable to the feelings ; it generally ceased in the
course of the night. The southerly winds sometimes blew with
very sudden and rather violent squalls, which, however, com-
monly subsided in an hour or two.
The clearness of the atmosphere was very remarkable ; the
moon and the stars appeared very brilliant, and the lofty moun-
tains of Corsica, with their snowy summits, were occasionall
to be seen by the naked eye rising above the south eastern
horizon at a direct distance of about 120 or 130 miles (English);
their forms were most remarkable a few minutes before sun-rise,
sometimes presenting very perpendicular sides, and often vary-
ing greatly in their apparent outline from day to day. This
mountainous island very rarely appeared unattended by clouds
even on clear, bright days ; their forms, I remarked, were gene-
rally Cumuli (owing no doubt to the coldness of the atmosphere
over the snows of those mountains) ; these Cumuli about sun-set
sometimes presented a grand and richly coloured mass towerin
above the horizon to an immense elevation, reflecting the sun’s
rays for some time after the sun had gone down.
The clouds which appeared in the field of our observation
sometimes afforded much interest in a meteorological point of
view. From the concave and sheltered situation of the plain of
Nice, so directly exposed to the south, the temperature of the
surface of this plain, as well as of the superincumbent atmo-
sphere, is rendered more or less considerable, especially as the
* This wind (styled one of “ les fléaux de la Provence), by which this part of
France is so much visited, after passing over the High Alps and their immense
snows and glaciers, takes its course with increasing violence towards the warm
atmosphere of the Mediterranean ; it is particularly violent in the valley of the
Rhone. A friend of mine travelling from cu northward up this valley, while
this wind was blowing with its usual fiercenessinformed me that he did not appear
to get clear of it until he had passed Lyons, although I found it still to prevail at
Marseilles and Toulon for some days after. It is piercingly cold and dry, at the
same time that it is violent, and in its course blows up the sand about the rivers
and the limestone dust off the roads in vast clouds over the country, which is parti-
cularly the case about Marseilles, where on those roads there is so much traffic. It
Jasts in general several days, increasing in velocity and coldness as it seemed
almost every hour. (‘* Laissez-le,” said a native to me, with a significant shake
of hishead, in reply to my observation as this wind was coming on, that it was not
so fierce as I was given to expect; and I had afterwards to remember his answer.)
Itis felt generally throughout Provence, particularly at Marseilles, Avignon, Mont-
pelier, &,
172 Remarks on the Climate, Situation, and [Sepr.
sun gets up towards the meridian. The temperature of the
lower stratum of air being increased, and consequently raritied,
it is evident that the upper region of the atmosphere above us
would also receive an increase of temperature, by the constant
succession or supply of warmer air from the region below, which
again (as it appeared) received its supply of cool air from the
most open quarter, viz. from the sea. This sea breeze, as L
have stated above, generally came on about nine or ten o’clock
in the morning, by which time the sun was sufficiently elevated
that its rays could bear upon the whole plain and sides of the
hills with effect; the breeze generally increased till about two
o'clock; and about sun-set subsided. This circulation, or
ascending current of the warmer air, seemed to have at times
considerable effect. upon the clouds which happened to pass in
cur zenith, and which were not too elevated to be out of its
influence. I have observed several instances of the atmosphere
in the morning being quite overcast with clouds, and apparently
(to an English eye) threatening rain, but which, about noon,
became quite fine and clear; and in the afternoon the clouds, to
my surprise, almost, and even wholly, to disappear (and this was
not an uncommon occurrence). It was rare indeed during my
stay there, that the sun was not to be seen and fe/t also in the
middle of the day. In one instance a north westerly current
brought up a quantity of clouds in detached Cwnuli, which, when
they had reached our zenith, were met by the sea breeze from
S.E. which carried them all back, and im a short time disap-
peared. At other times they advanced to the summits of the
neighbouring mountains, where they rested for the greater part
of the day, assuming the Cirrostratus form. Thunder storms, |
was informed, occurred very frequently in the summer, two or
three times in the course of a week in the neighbourhood of the
mountains, but that they seldom visited Nice (except at times
during the spring). I had an opportunity of remarking this on
_ the approach of a storm, one morning in the beginning of the
summer.*
In this fine Italian sky, if so it may be called, the clouds, as
a variety, often added much to the picturesque appearance of the
landscape ; it is not often, perhaps, that scenes are met with so
beautiful and so highly picturesque of the kind as the north-east
view of the town and role OF Nice, with the distant shores of
* Extract from daily observations respecting this on June 2:—‘‘ Fine day:
observed some finely illuminated Cumuli, with dark Cirri, traversing their sides,
rising up above the mountains to the north: as they rose (o a certain elevation, their
summits gave way, and spread, as if acted upon by a different state of electricity,
into a Cirri form; at length, about noon, several collected in the north intoa
dark, heavy mass of thunder clouds, discharging rain or hail over the mountains ;
the mass gradually approached our zenith, although the wind with us was blow-
ing in adirectioncontrary to it; but before it reached our zenith, it seemed to have
fallen into a different atmospheric medium, and I observed it soon began to fold
itself backward, and in an hour or two the whole seemed to be gone, or merely te
leave behind some light Cirri.”
3
1818.] Temperature of Nice. 173
France over the Bay of Antibes, about sun-set, and the reverse
view, viz. from the ramparts of Antibes, of Nice, with the moun-
tains that rise behind it in successive ranges, and the snows of
the Col de Tende, &c. bounding the picture.
The mildness of this climate, and the sheltered situation of the
country about Nice, render it a fine field for the lover of botany
to follow his favourite pursuit, a subject which I regretted [
knew so little about. It was, however, interesting to attend to
the geography of plants, which the gradual elevation of ground
from the shore to the summits of the mountains rendered very
remarkable, particularly in some species.
On the fertile plain of Nice flourished the orange and lemon
trees in gardens (of which there were above 60 different kinds) ;*
also the date palm (Phoenix dactylifera), the pomegranate (Pu-
nica Granatum), the Nerium Oleander, the cypress, different
kinds of geraniums, the sweet-scented Verbena, the myrtle, one
of the Gossypiums, or cotton tree, the olive, the white mulberry
(Morus Alba), which supply the silk worms, and many other
trees and plants ; and on the walls and rocks in warm situations,
the Cactus opuntia, or Indian fig, the caper shrub (Capparis
Spinosa), the great aloe (Agave Americana), to be seen in some
places ornamented with its stately flower 20 or 24 feet high.
On ascending the hills a few hundred feet, but few of these were
to be seen; the orange tree soon disappears; its region is very
limited in distance from, and elevation above, the sea; witht
respect to the former two myriametres (about 11+ miles) has
been stated by Risso to be its limit. The olive region may be
traced considerably higher up the hills, higher on their south
sides than on the north; this region, as near as I can guess, does
not much exceed in general 800 or 1,000 feet in elevation; its
distance from the Mediterranean I found, when travelling north-
ward from Marseilles, to be about 70 or 80 miles; it dwindles
away to a mere bush between Avignon and Pont d’Esprit, about
which place I lost sight of it. Above the olive region generally
appeared the Pinus Abies, the Pinus Sylvestris, or Scotch fir,
Juniperus Communis, the chesnut (Castanea vesca), &c.; upon
this region the snow in winter sometimes fell, and remained for
a longer or shorter period, according to circumstances.
Some attention to the geography of plants is useful in choos-
ing a situation most Os aa an invalid whose case
* Ina small publication, by Risso of Nice, of the different kinds of orange,
ie and lime trees cultivated in the Dep. des Alpes Maritimes, he divides them
as follows:
Species of the Orange (Orangers),........eeeeees 19
Bitter ditto (Bigaradiers) ......... ll
ECTIGES: (MRCS) ai\-, cic caieice'aesue.ce
————_— Cedratiers (Cedrat) .......... ac00- 3
————— Limoniers (Lemon)... ..0s0-.eeeeee 25
174 Remarks on the Climate, Situation, and [Serre
requires a warm climate; thus the olive and orange trees may
serve as useful subjects in this respect for the south of France.
About Aix and Nismes the olive is but a humble, lean-looking
bush, or standard, from about four to 10 or 12 feet high, requir-
ing the use of the pruning knife to bring it into condition for a
crop every other year: at Marseilles it increases in stature,
appearing as a small tree; at Nice it becomes a fine thick tree,
about 20 or 30 feet in height, bearing annually, and apparently
but seldom pruned ; and about two miles to the east of Nice,
near the town of Villefranche, a situation peculiarly sheltered
and exposed to the south, this tree appears to great perfection,
and affords an excellent, hard, and close-grained timber, which
is a good deal worked by the cabinet-makers and carpenters at
Nice. Again, the orange tree flourishes and brings its fruit to
perfection in the plain of Nice (some few of them under shelter
of Mont Cimiez I should guess were from 25 to 30 feet high) ;
the fruit is still finer in flavour and earlier matured at Ville-
franche ; the tree is also well cultivated and in high perfection
at Hyeres, though I understand that at Toulon, about nine miles
only distant, it requires the shelter of a wall, and at Marseilles
the shelter of a greenhouse in winter. And even in the neigh-
bourhood of Nice, it might in the same manner be observed,
‘that some situations were much more eligible than others in
point of shelter and warmth, though not so evident at first sight.
After a visit by a very cold, bleak, and violent mistrale in the
month called April, its mischievous effects were very observable
upon the tender vine shoots as well as upon the young green
leaves of the mulberry trees, in shrivelling them as if they had
been burned, leaving but a poor prospect for the next vintage,
and throwing back considerably the ensuing crop of silk. If
observed these effects particularly between Antibes and the
valley of the Var; also in many situations in the valleys about
Nice, which ran north and south; but in other places on the
south sides of the hills, the mulberry trees mostly escaped unin-
jured, and in some instances were to be seen in a flourishing
state at a little distance from others which were blasted, but
which had riot been so protected. The most protected situation
about Nice appeared to me to be the south side of Mont Cimiez,
or the plain between it and the shore, which includes the Croix
de Marbre, a quarter the most frequented by the English. Ville-
franche is undoubtedly a warmer and more sheltered spot, but
it is a place not to be compared to Nice for accommodations, or
even the necessaries of life, at which place the now frequent
visits of our countrymen for the benefit of the climate have
afforded the inhabitants the opportunity of learning English
wants and comforts. With respect to our consumptive patients
visiting so distant a spot for the benefit for the climate, it
appeared clear that unless they decide to go there at such an
early stage of the disease when they are able to take the air
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and exercise which this fine climate allows of with so little inter-’
ruption, the experiment would seldom prove successful. The
journey itself, of 800 or 1,000 miles, although alleviated by a
safe and easy water conveyance from Chalons to Avignon, is of
itself a heavy, and it may be a. painful toil to inflict upon the
sufferer ; yet the earlier the decision is made, the greater appears
to be the probability or certainty of ‘success, or recovery.
hope I may be excused for thus deviating a little from the
original subject of this communication ; but I am led to do so
by the hope of droppmg a hint or two that might be useful at
all to any concerned, or likely to be concerned, with the subject.
Upon the annexed scale (Plate LX XXIV), the maximum and
minimum of temperature for each day at Nice, taken by a Six’s
double thermometer (suspended about 15 feet from the ground
on a north aspect), are compared with those of L. Howard, as
published in the Annals. It may be observed how uniform the
daily temperature was at Nice comparatively with that in
England, the line indicating the maximum at Nice having for the
three winter months mostly confined itself within the 50th and
60th degrees of Fahr.; whilst that of England has marched
during the same period between the 30th and 55th degrees, its
sharp, angular course indicating the rapid changes of temper-
ature in our English climate. It may also be observed how
nearly the great depressions and elevations of temperature in the
two countries correspond in point of date.
The following is a brief, daily account of the weather at Nice.
Day. Wind. Remarks.
1816.
Dec, 1 N Fair; windy.
2 N Very fine; clear; warm sun.
3 E The same.
4 E The same,
5 NE Cloudy ; mild.
6 N Cloudy ; very mild.
1 NW The same.
8 Ww Cloudy ; fine; Cumuli.
9 SE Rain about sun-rise ; fine at noon.
10 NE Cloudy.
ll Ww Cloudy ; haze.
12 SE Fine, and warm sun.
13| SSE Wet mists ; drizzling rain.
14 WwW Fine, and about noon very clear,
15 Ww A little rain; clouded sky.
16 NW Fine; very mild evening.
17 NW .jFine; hot sun.
18 WwW Very fine and warm.
19 E Fine; wind cold; a gale of wind atseven p. m. from E.
20 NE _ |Clouded day; the mistrale cold.
21 NE {Fine ; cold wind; vbserved four spots in the sun.
22 NE Fine; clear; cold wind.
23 N Very fine and clear,
24 N Brilliant day; scarce acloud,
2a E The same.
176
Remarks on the Climate, Situation, and [Sepr.
Day.
1816.
Dec.
26
OS O95 0D %
= OO D3
1817.
Jan.
Feb.
COMO F HU 69
>
Wind.
NE
E
NE
NE
E
E
Remarks,
Cloudy, but pleasant.
Cloudy ; Cumuli; atnoon clouds went off; fine and warm.
Fine.
\Fine; Cirri; Cirrostrati.
Very fine ; warm sun.
Cloudy, but pleasantly mild.
Cloudy; wet mists, and a gentle shower ; little orno wind,
Light rain.
Rainy.
Fine, clear day; warm at noon.
Fine ; warm ; clear; Cirri.
Fine; thermometer rising rapidly, with a SW wind, to 634
in the shade.
Fine ; cold wind.
Fine; clear; cold wind.
Brilliant day, after a frosty night ; Cumuli over sea.
Fine.
Fine.
Rain last night; cloudy ; windy.
Fine ; warm at noon; one or two finely formed Cumuli were
to be seen over Corsica towering high above the horizon,
with Strati traversing them; sea calm.
Fine, and warm.
The same; at1l p.m. some distant lightning.
Very fine and clear; no cloud that I saw.
Fine morning ; afterwards cloudy, and a few drops of rain
fell.
Rain almost the whole day.
Heavy gales off the Devonshire and Cornwall coasts ; very
rainy ; clouds hanging upon the low hiils.
Heavy gales off the Devonshire and Cornwall coasts; storm
of wind and heavy raia last night ; rivers flooded.
Cloudy ; an additional coat of snow on the mountains since
these two or three days past.
Very fine and warm.
Fine ; afterwards, clouded sky.
Fine, ” and warm.
Very fine ; sultry, with the mist of an English summer's day.
The same.
NE—SE /Fine: a Mediterranean mist came towards us from the sea
Ww
E
NE
NE
NE
after yesterday’s warmth.
Fine, and warm.
The same.
The same,
Very fine and clear.
Very fine; hot sun.
SW—NE |Very fine; windy at night.
NE
ENE
Very fine.
Fine, and warm; fine night as usual,
The same ; Cirrostrati.
NE—SW |Very fine; Cirri.
E—S
N
E
The same; sea breezes.
Fine, and very warm sun.
Fine; sirocco in the evening ; clouded.
NE—E Cloudy morning; fine at noon.
SE—E |Clouded sky.
W
NE
The same,
Very fine, and hot sun.
NE—W [The same; Cirri about nine p.m.: a thunder storm; light-
ning very vivid, with some rain.
1818.] Temperature of Nice.
Feb. 15) N—S_ |Fine; Cirri.
Remarks.
.
16] N—S_ |Very fine; a few Cirri.
17| NW—SW |Very fine and clear; a few Cirri.
18} N—S_ |The same. °
19} N—S_ |The same,
20 — The same,
21 — The same.
22 NW _ |The same; much wind; a gale at one time.
23) NW—E |Brilliant day.
24, N—E_ j|Cloudy.
25 N Very fine and clear.
26| NE—S The same. :
27| SE—NW |Very fine; the upper current (NW) descended upon us in
the evening as the sea breeze fell.
28) E—SE /|Very fine; clear sky.
March 1 NE Very fine. - 5
2} N—SE /|Very fine, and warm.
3| N—SW |Very fine; therm. at 67%.
4 Ww Fine; therm. at 73; a hard gale to-day.
5} W—SW |Much wind; dark Cumulostrati.
6| N—W_ |Fine; but as the west current came on, clouds and a haze
came up.
7 Ww Fine day ; much wind.
8) NW The same.
9| N—NW |Very fine.
10} NW Very fine; windy.
11] N—SE [Very fine; windy.
12 N Fine.
13} N—SE |Very fine.
14) N—SW /|Fine morning; cloudy afternoon.
15) N—SE |Very fine; cloudless.
16) NE—SE |Very fine.
17 £ Cloudy ; very cold ; a few drops of rain.
18) N—S_ |Very fine.
19| N—ESE |Very fine.
20| N—E_ |Fine morning; at night, cloudy and rain.
21) N—E_ |Rain, a.m.; fine, p.m.
22| N—S~ |Much snow fallen on the distant Alps; fine, a.m.; cloudy,
p- m.
23 N Cloudy, but mild,
24| N—S_ |Fine.
25) N—S_ |Very fine.
26) E—S_ |Very fine.
27) N—E /|Very fine.
28| N—NE Very fine morning ; hazy, p.m.
29| N—SE Very fine.
30| N--SE (Very fine.
31| NE—E |Very fine; evening windy.
April ! E Cloudy ; fine, p.m,
E—SE |Vine.
2
3 SE Fine,
4) E—SE /Fine.
5 E Very fine.
6 E Fine,
4 E Fine,
8| E--SE /Fine.
9 _ Cloudy,
10 _ Vine.
il — Cloudy; showery.
12| _ Fine.
Vou, XII. N° Til, M
178 | Remarks on the Climate, Situation, and = [Serr.
Day. Wind, Remarks.
1817.
April 13 — Fine.
14 — Cloudy.
15 _ Fine day.
16 — Fine.
17 —_— Rainy.
18 — Fine,
19 to 23 omitted.
24) N—SE Very fine.
25, NE—SE |Very fine.
26) NE—SE |Fine.
Q7 N Rain; snow on the mountains; very cold.
28} N—S_ jFine, and clear,
29| N—SE /jFine; and cloudy, p.m.
30 NE The same,
May 1 and 2, omitted.
May 3 E Fine ; wheat in the ear.
: 4 SE Very fine.
5 SE Very fine, and clear of clouds.
6 SE Very fine.
7 SE Fine ; hazy.
8 E Hazy ; clouds reticulated; a brisk E. wind; a firefly seen.
9 SW Cloudy ; showery.
10 SW Fine morning ; large Cumuli above the mountains.
iat S Heavy rain early, a.m.
12 E Very fine and clear.
13} SE—NE /|Fine day, and clear; but the N.E. current brought up
clouds, p.m.
14 SE Fine; cloudy; Cirrostrati.
15 SE Fine; very hot; Cirrostrati.
16 SE Hazy; some rain; fresh breeze.
17 E Very fine, and hot; contorted Cirri in the zenith; soon
after, a breeze.
18 E Clouded, with a very hard easterly gale throughout the day ;
a few drops of rain,
19} ESE ({Overeast; dark Cirrostrati over a Nimbus; rain began
towards dusk, but slight.
20 s Clouds very low; rain, a.m.; as the sun got up, the clouds
were penetrated, and began to move away ; one part rose
in a mass to a great elevation, the summit assuming a very
fine Cumuli form, reflecting the rays of thesun inadazzling
manner,
21} SSW_ {Very clear and fine; the snow on the Corsican Alps dis-
tinctly visible, lying in the defiles distant about 120
miles.
22 SW Fine, a.m, fine Cumuli, one of which broke over one of the
mountains, whitening it with snow, or hail; auother
broke overus with a few drops of rain; some lightning over
the mountains in the evening.
23 SW Very fine and clear morning ; some plumose Cirr? overhead,
and the wind soon yot up from W.S.W. toa stiff breeze,
and brought up a haze.
24) SW . jVery fine and bright; a fine Cumulus, highly illuminated in
the N., over the summit of one mountain.
25 SW Cloudy ; some rain; fine, p.m.
26 SW Cloudy; some rain; afterwards sky cleared, aud brilliant
afternoon,
Se
1818.] Temperature of Nice. 179
Day. Wind. Remarks.
May 27 SW Fire ; windy; Cirri.
28 SW Very fine; windy.
29 W Fine; windy; Cumuli.
30 SE Fine; Cirri.
31 SE Fine.
SEE EERE niteneememimenesememmememereemennnneeremeceereeeee
SIX MONTHS OF OBSERVATION.
ArrTIcLE IV,
Memoir relative to the Annular Eclipse o the Sun, which will
happen on September 7, 1820. By Francis Baily, Esq.
[The following essay, a few copies of which have been printed
for private distribution, was transmitted by the author to the
Editors of the Annals. The interesting nature of the subject
will, they are persuaded, render it acceptable to their scientific
readers. } ‘
Tue solar eclipse’ which will happen on Thursday Sept 7,
1820, will be the greatest of all those which have happened in
this part of Europe ever since the year 1764; and indeed of all
those which will again happen here before the year 1847. Like
the two eclipses above alluded to, it will be annular: that is, the
disc of the moon will not wholly cover the disc of the sun ; but,
in certain parts of the earth, the sun will show the appearance
of an annulus, or ring, round the body of the moon; the position
and magnitude of which will depend on the situation of the
spectator. In no part of England, however, will this annular
appearance be observed :* but, on the continent, in any part of
that tract of country which extends nearly in a straight line
from the north of Westphalia to the south of Italy, the inhabi-
tants will have an opportunity of beholding this singular pheno-
menon.
Annular eclipses do not appear to have been noticed by the
ancients, who probably confounded them with partial ones.
Indeed, the only authentic accounts of any well observed annular
eclipses in this part of Europe (besides the one in 1764 above-
mentioned) are those of Feb. 18, 1736-7, and of July 14, 1748; +
* The eclipse, however, will be annular in the Shetland islands: and it will be
of considerable magnitude along the whole eastern coast of Great Britain.
* See a detailed account of these eclipses, and of the phenomena attending
them, in the Phil. Trans. vol, x1, p. 177, and vol, xly. p. 582,
M 2
180 Mr. Baily on an | [Szrr.
the former of which was observed by the celebrated Colin
Maclaurin at Edinburgh, and the latter by the Earl of Morton
and Mr. Short, at Aberdour Castle, near the same place. Indeed
the annular appearance of the eclipse of 1737 was confined
principally to Scotland; and the eclipses of 1748 and 1764,
although visible to a great part of Europe, were not so generally
observed as could be wished, on account of the badness of the
weather ; so that we have not any very considerable degree of
information respecting this kind of solar eclipses. Moreover at
those periods the lunar tables were so defective that it could not
be predicted, with any degree of accuracy, where the annular
appearance would be visible ; so that many valuable observations
were probably lost on that account. This difficulty, however, is
in a great measure removed by late improvements, not only in the
lunar tables, but likewise in the analytical investigations relative
to the calculation of eclipses; although the computations are
still very laborious and troublesome.
Prior to the total eclipse which took place in London in the
year 1715, Dr. Halley published an account of the path of the
moon’s shadow across the island of Great Britain; and called
on the inhabitants to note down their observations and forward
them to him, in order that he might afterwards compare them,
and thereby correct the elements made use of in the calculation
of eclipses. The good effect of this measure may be seen in the
report which that illustrious astronomer afterwards drew up, and
sent to the Royal Society, and which is inserted in the Phil.
Trans. No. 343, vol. xxix. p. 245. Mr. Maclaurin, likewise,
previous to the annular eclipse in 1737, before mentioned, wrote
to several persons in the country, “ desiring that they would
determine and note down the duration of the annular appearance
as exactly as possible, in hopes, by comparing their observa-
tions, to have traced more correctly the path of the centre and
limits of the phenomenon.” And in 1748 Mr. Alexander Monro
(Professor of Anatomy of Edinburgh), by Mr. Short’s desire,
wrote to all his friends in different parts of the country, to pre+
pare in the best manner they could for the most exact observa-
tion of the annular eclipse which was about to take place in that
year. And he regrets that he did not make this application
earlier ; for he remarks that had “ my request of having the
duration of the annular appearance measured been made more
public before the eclipse (after Dr. Halley’s example in 1715), I
doubt not but I should have been able to have given a more
exact account of the progress of the centre of this phenomenon
and of its limits.” M. de L’Isle also, with a similar view, pub-
lished a notice to astronomers * in order, as he observes,
““exciter les curieux de Europe, qui powront voir l’éclipse
% Avertissement aux astronomes sur V’éclipse annulaire du soleil que Von attend le
25 Juillet, 1748. (t was published, however, only three mouths prior to the eclipse
taking place; so that there wa; scarcely time-for it to get into general circulation.
1818.] Annular Eclipse of the Sun, 181.
annulaire qui doit arriver, d’y apporter toute l’attention possible,
et de faire, de bonne heure, toutes les dispositions nécessaires
pour la bien observer; afin de nous procurer tous les avantages
ue l'on en peut retirer pour l’astronomie, la géographie, et la
physique.”
It is worthy of remark that this eclipse (1748) was the first
that the celebrated Lalande (to whom the astronomical world is
so much indebted) ever saw. He was then only 16 years of
age; and the impression which it made on him fixed his future
pursuits in life, and induced him to become an astronomer. It
indeed excited so much attention in Europe, that the King of
France (Louis XV) went purposely to Compiegne in order to
observe it, attended by the Abbé N ollet, and Messrs. de Thury
and de la Condamine ; and furnished with every convenient
instrument for the purpose. The royal astronomer there made
several important observations.* M. Lemonnier likewise under-
took the journey from Paris to Edinburgh, furnished with proper
instruments, purposely to observe it during its annular appear-
ance; and he afterwards published some important remarks
thereon.+ M. de L’Isle, above-mentioned, published also a
paper en the subject, entitled “ Nouvelle Théorie des kiclipses,”
founded entirely on the recent observations that had been made. ft
M. Pingré &fterwards added very considerably to these reflec-
tions in his interesting memoir, entitled “ Recherches sur la
Longitude des plusieurs Villes.§ Méchain likewise madea great
many calculations relating to it, from the manuscript collections
of M.de L’Isle. But it was reserved to Lalande, fifty years after
Wie event, to deduce the most important conclusions from this
“singular phenomenon, in his paper “Sur la grande Eclipse
“Annulaire de 1748.” | if
Considering, therefore, the interest which has always been
attached to this kind of phenomena, and the important conclu-
sions to be drawn from them, I was somewhat surprised to find
that no particular notice has been taken of the ensuing eclipse
either in the Connaissance des Tems, or in the Nautical Alma-
nac; but that it is merely announced there in the usual formal
manner, without a single remark on the occasion. It is true
that M. Bode, in his ephemeris, published at Berlin, has given
(as usual) a general outline of the eclipse, together with a ma
descriptive of the phases ; but he has not called on the inhabi-
tants to look out for this phenomenon, nor drawn their attention
to any of the subjects which it is most desirable they should
observe. In order to supplyhis defect, as far as my humblé
* The same monarch had also made several observations on the eclipse of 1737,
at Versailles, attended by the celebrated Cassini,
+ See the Memoires de Acad, Roy. des Sciences for 1765, p. 468,
} Ibid, for 1757, p. 490,
§ Ibid, for 1766, alt,
| See Memoires de l'Institut, (Scien, Math. et Phys.) vol, ii, p. 364,
182 Mr. Baily on an [Serr.
efforts will avail, I have drawn up the following memoir, under
the hope that it may induce others, who have more leisure, and
are at the same time more conversant with the subject than my-
self, to pursue the inquiry, and suggest further hints to those who
may have an opportunity of observing this rare phenomenon.
M. de L’Isle, in his Abbptissenient above alluded to respecting
the eclipse of 1748, suggested the advantage and propriety of
some scientific person in the principal states of Europe through
which the shadow of the moon’s umbra passed undertaking to
announce to the inhabitants the several observations which it
would be proper for them to make; and afterwards to collect
and arrange such observations for further investigation, if suffi-
ciently convinced of their accuracy. A similar plan might be
adopted in the present instance; and, from the more general
diffusion of science, would be more likely to be attended with a
beneficial effect. Such collections of observations (when made)
should be sent by the different collectors to one or more of the
principal astronomers of Europe, in order that they might be
finally investigated, and the result laid before the public.
With that view I would take this opportunity of requesting
those into whose hands the present memoir may fall to circulate
it as much as possible on the continent, and amongst those
persons who, from their connexion with any foreign literary
journal, may be likely to diffuse the subject of it amongst the
inhabitants of that part of Europe and Africa where the annular
appearance will be observed. Such of our own countrymen,
likewise, that may be travelling in any of the provinces on the
continen’ here alluded to, will promote the interest of astronomy
if they would carefully note down or collect any of the circum-
stances hereinafter alluded to, or indeed any other remarkable
phenomena that may happen during this eclipse. I shall be
happy to receive any observations of this kind that’ may be
forwarded to me, and will preserve the result of them, as above
proposed, for a future investigation.
The elements of the present eclipse I have computed from
M. Burckhardt’s tables of the moon, and M. Delambre’s tables
of the sun; and they are as follow. The ecliptic conjunction
will take place on Sept. 7, 1820, at
i* 51’ 37” 3 p.m. apparent time, or Ae
1 49 26 2p.m. meantime .. oud bat Greenwich :
And at that time we shall have the
True longitude of the luminaries .......... 5% 14° 47’ 40-7”
True latitude of the moon (north).......... 0 00 44 39:4
Mcon’s horary motion from the sun. ...... 0 00 27 1:7
horary motion in latitude (decreasing) 0Q 2 42:0
horizontal parallax. ........2+e.+: 0 00 53 53°0
————— semidiameter . Sai edb ime ehceeasn CO 00 14 41:0
1818.] Annular Eclipse of the Sun. 183
Sun’s semidiameter. .........seceeececes OF 00° 15’ 54:8”
horizontal parallax ......+.eeeee00. 0 00 O00 87
declination (north) ........e0..06.. 0 5-59 41:0
From these elements it may be determined that the moon’s
shadow first touches the earth’s disc at 11" 23’ a.m. apparent
time at Greenwich, in N. lat. 59° 43’, W. long. 90° 50’;*
and that it finally leaves it at 4 392’ p.m. apparent time at
Greenwich in N. lat. 3° 21’, E. long. 20° 25’. Consequently the
total duration of the general eclipse to the inhabitants of the
earth will be about 5" 17’; but at no one place in particular will
the duration be much more than half that time.
The central path of the moon’s shadow across the earth’s disc,
which is the most material circumstance in inquiries of this °
nature (since it serves to point out those parts of the world
where the eclipse will be seen annular), may be determined with
considerable accuracy from the principles laid down by M.
Delambre in his “ Traité d’ Astronomie” (vol. i. p. 384); and,
agreeably to the formule which he has there given, | have
carefully computed the following table, which shows the several
points (expressed by positions of latitude and longitude) through
which the centre of the moon’s shadow will pass in its progress
across the earth’s disc at the several times therein mentioned.
The first column denotes the apparent time at Greenwich at the
moment when the centre of the moon’s shadow passes the given
points laid down in the second and third columns, and the last
column shows the corresponding apparent time at those places.
Apparent time at
Greenwich, p.m.
Latitude North, |4°™situde from Green-| Apparent Time at the
i wich, Place.
rea’ be 39" 81° 39’ 29! W. 149° 32’ 55” 2> 56’ 27” am,
55 600 83 39 34 129 44 37 4 16 2
Rear OO 82 24 34 42 38 12 1On D BF
8 16 16). 6. val TE (OSS PRLS 12°. (Or 30
10 O 45 23 11 14 31 Al 12 Tl- 53 p.m.
20 O 69 9 Al D (5281 12 56 31
30 0 64 13 27 0 46 50 1 26 53
40 O 59 4T 3l E. 2 50 42 1 51 23
50 =O 55 44 40 5 48 32 213 %
mp’ 8 51 56 26 8 26 4 2 33 44
10 O 48. 18 42 10 5% 6 2 53 48
20 O 44 49 25 13 32 32 3 14 10
30 0 Al 25° (32 16 23 32 3 35 34
40 0 38 3 53 19 44 0 3 58 56
50 O 34 AO Al 23 59 43 4 25 59
a0. .-0 he dowel 30 24 13 h 1 37
8 ll 27. 10 30 46 2 4 6 12 19
From this table it will be seen that the central eclipse com-
mencesin N, lat. 81° 39’ 29”, W. long. 149° 32’ 55”, when the
sun and moon will rise together (the centre of the moon being
* Allthe longitudes in this memoir are reckoned from the meridian of Greenwich,
184 Mr. Baily on an [Sepr.
directly on the centre of the sun’s disc) to the inhabitants of that
part of the globe, at 256’ 27” in the morning, corresponding to
125 54’ 39” (or 0» 54’ 39” *) in the afternoon at Greenwich :
that the sun will be centrally eclipsed on the meridian (or
exactly at noon) in N. lat. 76° 6’ 21”, W. long. 17° 3’ 15”, when —
it is 1" 8’ 16” in the afternoon at Greenwich; and that the sun
will set centrally eclipsed in N. lat. 27° 10’ 30”, E. long. 46° 2’
4” at 6" 12’ 19” in the afternoon, corresponding to 3" 8’ 11” at
Greenwich.
If-the points mentioned in the second and third columns of
the above table be marked on a good map, and lines be drawn
connecting these points, we shall have the path of the centre of
_ the moon’s shadow across the globe. Whence it will be seen
that the centre of the shadow, having entered the earth’s disc
near the North Pole,+ will proceed between the Shetland islands
and the coast of Norway down the North Sea, and enter the
continent of Europe on the coast of Westphalia, about half way
between the Ems and the Weser. _ It will thence proceed, nearly
in a straight line, across Germany and the Tyrol country, and
enter the gulf of Venice about mid-way between Trieste an
Venice. ‘Traversing that gulf it will cross the heel of Italy ;
and, after skirting the coast of the Morea and Candia, will pass
directly over Alexandria in Egypt, and finally leave the earth in
Arabia, near the Persian gulf.
If we set off two other lines on the map parallel to this central
line, one on each side thereof, and each at the distance of about
130 geographical miles from the central line, the intermediate
space between these two boundary lines will nearly { represent
the path of the moon’s wumbra; and will show all thos® places
where the eclipse will be seen annular, or where the whole body
of the moon will appear on the face of the sun. Some uncer-
tainty, however, may exist with respect to those towns which are
situated near the borders of the umbra, such as Rotterdam, Aix
la Chapelle, Liege, Treves, Freyburg, Parma, Rome, and other
places on the one side; and Magdeburg, Leipsic, Ragusa,
Athens, and other places on the other side of the central path ;
since the eclipse may or may not be annular in the neighbour-
hood of those towns according to circumstances. Nevertheless
at all those places, and indeed to the whole of Europe and to a
* That is, 54’ 39” after 12 o’clock at noon. The English astronomers begin the
day at noon; but the French reckon from midnight, as in the civil mode of reckon-
ing, There cannot, however, be any ambiguity in the present case as to the 12,
+ It will traverse the supposed polar basin, and the north east coast of Green-
land, the object of so much laudable curiosity at the present moment; so that if
the adventurous nayigators to those parts should not have returned before the date
of this eclipse, they will probably observe it in. those high latitudes. :
} It must be evident to those acquainted with the principles of astronomy, that
the umbra will not be exactly of the same width in any two points of its course;
but willbe constantly varying. It will not, however, undergo any material alter-
ation in its progress across the continent of Europe,
1818.] Annular Eclipse of the Sun. 185
great part of Asia and Africa, the eclipse will be visible ; differ-
ing only in magnitude according to the situation of the spectator.
But, in no part will it be annular except at those places which are
situated within the limits of the umbra, as above-mentioned.*
Those persons who happen to be situated on the western
border of the umbra will, at the time of the middle of the eclipse,
see the wpper limb of the moon in contact with the upper limb
of the sun; and consequently the unobscured portion of the sun’s
disc will be seen round the under part of the moon. On the
contrary, those persons who are on the eastern confines of the
umbra will see the /ower limb of the moon in contact with the
fower limb of the sun. Whilst to those who are stationed
_ directly in the central path, the centres of the sun and moon
will appear evact/ly to coincide ; and an uniform luminous ring,
equal in breadth to about , part of the sun’s diameter, will
surround the body of the moon.+
As there are no two points on the face of the globe where the
visible appearances of any solar eclipse are exactly alike, it
would be an endless task to compute the phenomena for any
considerable number of places; and the usual mode amongst
astronomers is to give a general outline of the path of the moon’s
shadow, and to calculate the particular circumstances of the
eclipse forthe metropolis only, or for some known observatory ;
which calculation may be easily adapted to other parts of the
kingdom. The notices which are given in the various epheme-
rides on this point are merely for the purpose of informing
astronomers to /ook out for, and note down these phenomena ;
and the observations thus made are afterwards collected and
compared together. Under these circumstances the reader
must not expect to find the exact time and appearances of this
eclipse computed for every place on the continent. It will be
sufficient for his purpose if he knows at what time of the day he
ought to look out for its commencement, and at what point of
the sun’s disc he ought to fix his attention in order to observe
the first point of contact. The following table will show nearly
these several particulars for the diflerent places therein men-
tioned ; and will assist the observer in his computations for any
other place within the umbra. These values are deduced
merely from a projection of the eclipse, and are consequently
given as approximations only, and by no means as the exact
values ; for, where it is required to have the time true to the
nearest second, the observer must calculate the phases of the
mer 0 for the precise spot where he happens to be stationed.
The angles from the vertex are all reckoned on the right hand
* In order to give a general view of the path of the umbra across the continent
of Europe,’ a map of the same (Plate LXXXY) will be given tu accompany the
remainder of the paper in our next number.
+ The sun will be elevated on that day above the horizon about 34 degrees to
that part of the continent over which the centre of the moon’s umbra passes; con-
sequently the increase of the moon's semidiameter will be about 73 seconds.
186 M. Chevreul on Fatty Bodies, and _ (Serr.
side of the sun, as the moon always makes the first impression
on the sun’s disc on that side.
Time of Commencement.
TS a ee | ig le from: the
Mean Time at |Mean Time at the Vertex.
Greenwich, p.m.| Place, p.m.
Place of Observation.
oe
Lerwick (Shetland)....) 12" 9’ | beatae 52°
Bergen (Norway). .... 15 37 61
Amsterdam .......... 26 46 58
Aix la Chapelle. ...... 30 54 61
Pampas Ue. oyecicies 31 Pret 65
WEIPSIC! Oa. wi ee cect es 37 264 71
MPANGIOUE iy Sn ee ae ence 34 1 64
WAH Hate emai ph lo dei 441 411 76
WUD AEE ite pasteles, aca acs 42 28 70
" TION aa are kis sibs wa. 39 13 ‘65
WERIEO', oot cee see os 48 or 72
DP BlNEe he sows ew e's on 50 35 ce
BUC T, shale cis 2 a e's 56 46 76
Naples 0... ..6s eevee. | yeaa 58 81
Mihens ss . bes ce wats 18 21 G3", 97
Wiewandtia. i256. os e ke 40 3 40 109
The whole duration of the eclipse will, at all these places, be
rather more than two hours and three quarters. But the dura-
tion of the annulus will not, in any place, exceed six minutes ;
and in some places (at the confines of the umbra) it will be
momentary. ‘The nearer the spectator happens to be to the
centre of the path of the moon’s umbra, the longer will the
annular appearance continue. .
(To be continued.)
/ ARTICLE Y.
Researches on various Fatty Bodies, and particularly on their
Combinations with Alkalies. By M. Chevreul.*
Arrer noticing the imperfect state of our knowledge on the
subject of saponification, and the mistaken ideas that have been
* M, Chevreul has, for some years, been assiduously directing his attention to
this subject, and has, from time to time, published an account of his experiments
in a succession of papers inserted in the Annales de Chimie; the first of them
appeared in the 88th volume of that work ; they have been continued at intervals;
and, as we learn from the’ number for April last, are not yet completed. We
propose to give an abstract of the whole ; but as the contents of the earlier of them
may probably be known to many of our readers, we shall pass them over ina
more brief manner. 3
1818.] their Combinations with Alkalis. 187
entertained respecting it by preceding chemists, the author
gives an account of a new compound, which he had discovered
in examining the soap which is composed of hog’s-lard and.
potash. When this soap is digested in a large quantity of
water, a part of it is dissolved, while a portion, which is inso-
luble, is deposited in the form of small brilliant scales, which he
calls pearly matter (matiere nacrée). These scales were purified
by being repeatedly washed in cold water, and afterwards
digested in alcohol, to remove from them the soluble soap and
the various impurities which they contained ; they were subjected
to the action of diluted muriatic acid, by which they were
decomposed, and a new animal principle was obtained, to which
the name of margarine was apphed, in consequence of its pearl-
like aspect, and the property which it possesses of communicat-
ing the pearly lustre to the combinations which it forms with
salifiable bases.
The properties of margarine are then described; it is of a
early-white colour, without taste, of a faint odour, a little like
that of white wax, it is lighter than water, and at 134° * melts
into a perfectly limpid colourless fiuid, which, by cooling,
crystallizes into brilliant white needles. By distillation, marga-
rine is partially decomposed ; it is insoluble in water, but is very
soluble in alcohol when heated to 167°; as the alcohol cools,
the margarine is precipitated, or if the solution has been satu-
rated, the whole is converted into a solid mass.
The pearly matter, formed by the combination of margarine
with potash, was next examined. All the potash being very
carefully separated from it by means of diluted muriatic acid,
and the quantity of muriate of potash thus formed being accu-
rately ascertained, it was calculated to be composed of
Margarine....... O1QL «12... . 100-0
Potasli.' Gissies BOO cis de aS
100°00
Cold water has no action on the pearly matter; but boiling
water partially separates the potash from it. Ye is less soluble
in alcohol than margarine ; 1f water be added to the alcoholic
solution, a precipitate is thrown down, which appears to contain
a smaller proportion of potash than the pearly matter ; it was
found that about + of the alkali was united to the water, Ifthe
substance which is separated from alcohol by water be twice
dissolved in alcohol, it is deposited on cooling in its original
state, composed of 100 parts of margarme to 8°83 parts of
potash.
M. Chevreul was then induced to examine, whether, if
* The degrees of temperature in this abstract are always measured by fahren.
heit’s scale,
188 M. Chevreul on Fatty Bodies, and [Szrr.
margarine be presented to a heated solution of potash, contain-
ing a considerably larger proportion of alkali than was necessary
to convert it mto the pearly matter, a more alkaline compound
would be formed. Upon making the trial, this was found to be
the case; by digesting in water a quantity of potash and marga-
rine, a white matter was formed, which was soluble in heated
alcohol, and was deposited from it as it cooled in the form of
small needles, which, when treated with muriatic acid, were
found to be composed of 100 parts of margarine, and 17-77 parts
of potash, or almost exactly double the proportion of potash in
the pearly matter described above. This compound of margarine
and potash is white, not so soft as the pearly matter, and
slightly alkaline to the taste; it is decomposed by water, the
pearly matter being reproduced and the additional quantity of
potash separated. This decomposition, however, only takes
place when the quantity of water employed is large ; for if it be
used in small quantity, the decomposition is only partial, and a
thick transparent mucilage is formed. M. Chevreul regards this
as a saturated compound of the two substances. Margarine
decomposes the subcarbonate of potash, carbonic acid is disen-
gaged, and the pearly matter is formed.
As it appears that margarine possesses some of the leading
properties of acids, it becomes a question for consideration, how
far it is entitled to the denomination of anacid. {tis necessary,
therefore, to determine what are the characters of acids; and
M. Chevreul states the following as those which have been
generally consideréd to be essential ; the sour taste, their attrac-
tion to the positive galvanic pole, their neutralizing salifiable
bases, and their effect upon vegetable colours. The value of
these several characters, as indicative of acidity, is then dis-
cussed; it is stated that the sour taste is not found in all acids,
that the attraction for the positive pole is not confined to acids,
and that the same is the case with the neutralization of alkalies ;
with respect to the effect of acids upon vegetable colours, that.
the reddening of litmus has been generally regarded as the most
characteristic property, and that no body which is considered as
an acid is destitute of it. Upon the whole, the properties of
margarine are such as have generally been supposed to entitle
a body to the denomination of an acid; for it not only reddens
litmus, but it separates potash from carbonic acid, and forms
combinations that are, in all respects, analogous to neutral salts.
ts composition may, perhaps, appear an objection to this deci-
sion; but it is now generally admitted by the modern chemists,
that, in the classification of bodies, analogy of properties is to
be considered more than composition.
M. Chevreul’s Second Memoir.*
In the former paper, the author had examined the nature of
_* Abstracted from Ann, de Chim, xciv, 80.
1818.] their Combinations with Alkalies. 189
one of the compounds resulting from the union of hog’s-lard
and potash, which he found to consist of the alkali and marga- »
rine. He now proposes to examine the other compound, which
differs from the former in the obvious and essential circumstance
of being soluble in cold water. ;
M. Chevreul began by carefully purifying the fat, and after-
wards digested 250 parts of it with 150 of potash for two days,
at a temperature of about 175°, by which the fat was completely
dissolved ; the compound became opaque, and a yellowish fluid
spontaneously separated from it, the nature of which was exa-
mined. It was found to consist of the carbonate of potash, with
a great excess of base, arising from too large a proportion of
potash having been added to the fat, a little acetic acid, an
aromatic principle, and the sweet principle of otls. The soap
itself was next examined : it was completely dissolved by boiling
water; but as the fluid cooled, a large quantity of the pearly
matter separated, and it required 10 successive operations, per-
formed at an interval of several days, to remove all this matter
from it. The solution of the pure soap was decomposed while
hot by pure tartaric acid; the fat appeared in the form of white
masses, which melted into a yellowish oil. The fluid which
contained the acidulous tartarate of potash was poured off and
distilled, and a quantity of acetic acid, of the aromatic principle,
and a little of the sweet principle, were procured. The fat,
which had been separated from the potash by the tartaric acid,
was of a yellow colour, melted at about 60° ; its weight compared
to that of the fat originally employed was as 120 to 250. These
120 parts were melted, and added to 72 parts of potash, dissolved
in 480 parts of water, at the temperature of 86°. When the
soap thus formed was added.to cold water, a very small quantity
only of the pearly matter was precipitated ; but this was found, by
repeating the experiment with a smaller quantity of potash, to
depend upon an excess of alkali preventing the separation of
the pearly matter; for under these circumstances, a portion of
it was still deposited. When by this means the pearly matter
was completely separated, the fat was obtained nearly in a fluid
state, and was then found to possess the following properties.
{t had a rancid odour and taste; at the temperature of 66° its
specific gravity is *898; at about 43° it concretes into white
needles ; while it remains fluid it possesses a light yellow colour,
similar to that of olive oil. Suspecting that this yellow colour,
as well as that of other oils and resins, depended upon a matter
extraneous to it, M. Chevreul endeavoured to separate it by
boiling the fluid fat with carbonate of barytes, in the proportion
of two parts of the latter to one of the former, mixed with a
quantity of water. The result of this operation is the disengage-
ment of carbonic acid, and the combination of the fluid fat with
the barytes, so as to form a yellow, viscid, saponaceous mass.
5
190 M. Chevreul on Fatiy Bodies, and [Seer.
By separating the water, evaporating it, and treating the solid
residue with alcohol, a quantity of yellow colouring matter is
rocured, while the soap of barytes was left pure and colourless.
The next object was to ascertain the composition of this soap :
for this purpose a portion of it was put into a platina crucible,
which was then gradually raised to a red heat, by which a quan-
tity of carbonate of barytes was obtained, combined with a
minute portion of carbon; sulphuric acid was added, and by
comparing the quantity of sulphate of barytes formed with the
soap employed, he determined the composition to be,
PUNE. i oscte one iL LOD aah va eee et» BO
BATGRCS cian. 00. ney SAO, helde sb seiea's bin Se ee
100-00
By decomposing this barytic soap with sulphuric acid, the
fluid fat is separated im a very pure state, and was supposed,
like the pure margarine, to possess the power of reddening
litmus. a
The fluid fat seems to be capable of forming two combinations
with potash ; the first, with a minimum of alkali, which is gela-
tinous, soluble in alcohol, but insoluble in water; the other is
soluble in water, but appears to be decomposed into potash and
into the other species of soap, when it is diffused through a
large quantity of fluid. Water appears to exercise the same
kind of action upon the soap of the fluid fat as upon that of
margarine ; that is, it reduces it to potash and the super-soap ;
a greater quantity of fluid and a longer space of time are, how-
ever, necessary to complete the operation. ‘The experiments
which were performed in order to investigate all these points
require a very long space of time for their completion, some of
them as much as 18 months, and they are among the most
elaborate in the whole science of chemistry. The general con-
clusions which the author deduces from his experiments are,
that the soap formed by the union of lard and potash is not a
mere binary compound, but is composed of margarme, fluid fat,
a volatile oil, and an orange-coloured matter. These bodies are
saturated with potash ; the first two exist in a much greater
proportion than the last two, and may be regarded as the essen-
tial constituents of soap. The experiments which have been
related above, and the conclusions to which they lead, enable
us to explain the manner in which soap acts when it removes
grease from stufis. It in fact depends upon a portion of the
alkali being set at liberty, and thus being enabled to act upon
fatty substances, in consequence of the decomposition of the
soap of margarine by the addition of water. ‘The same decom-
position may be effected in the soap of the fluid fat, provided it
be diluted with a sufiicient quantity of water; but probably
1818.] their Combinations with Alkalies. 191
the principal operation of this substance is to yield to the fatty
matters a portion of its alkali, so as to form them into a super-
soap, while it is itself reduced to the same state.
M. Chevreul’s Third Memoir .*
The object of this memoir is to ascertain whether the bodies
which are found after the process of saponification are the essen-
tial products of that process, or if they previously existed in the
fat, and in this way to become acquainted with the theory of
saponification and with the composition of fat. M. Chevreul
first inquires whether the acetic and carbonic acids, which are
found in certain stages of the operation, are essential to it; and
the result of his inquiry is, that they are not so, but that they
depend upon some impurity in the substances employed. He
next inquires whether oxygen gas be necessary to saponitication ;
and by forming a portion of soap in a situation’ where it was
deprived of all contact with the air, he found that it was not
necessary for the union of the fat and the potash, nor for the
separation of the pearly matter, provided the soap be diffused
through a sufficient quantity of water.
The next topic is respecting the change which the fat expe-
riences during saponification ; and in order to ascertain this
point, M. Chevreul enters into a detailed examination of the
nature and properties of fat before and after it has undergone
this process. The differences were found to be considerable :
besides a change in colour and consistence, the melting point is
different, being 78°5° for the fat in its natural state, and 103°
after saponification ; in the former state it is nearly insoluble m
alcohol, and does not redden litmus, while in the latter state it is
extremely soluble in alcohol, and powerfully affects the colour of
litmus. We must, therefore, conclude, either that the fat has
experienced a considerable alteration by the action of the potash,
or that it originally consists of margarine, fluid fat, together with
a colouring, an odoriferous, and a sweet principle; and that
these bodies have so strong an affinity for each other as: to
conceal their specific properties ; it is, however, very difficult to
conceive how this could be the case, when we consider the
nature of the difference which there is between the two bodies.
In order to throw further light upon this point, M. Chevreul
proceeds to investigate whether fat ought to be considered as a
simple proximate principle. By dissolving the fat in a large
quantity of alcohol, and observing the manner in which its
different portions were acted upon by this substance, and again
separated from it, it is concluded that fat is composed of an o7/y
substance, which remains fluid at the ordinary temperature of the
atmosphere ; and of another fatty substance which is much less
fusible. Hence it follows that fat is not to be regarded as a
* Abstracted from Ann, de Chim. xciv, 113,
192 M. Chevreul on Fatty Bodies, and [Szrr.
simple principle, but as a combination of the above two princi-
ples, which may be separated without alteration. One of these
substances melts at about 45°, the other at 100°; the same quan-
tity af alcohol which dissolves 3-2 parts of the oi/y substance
dissolves 1:8 only of the fatty substance ; the first is separated
from the alcohol in the form of an oil, the second in that of
small silky needles. We perceive that the above substances
differ as much from margarine and fluid fat as natural fat differs
from that which has been saponified.
Each of the constituents of natural fat was then saponified by
the addition of potash; and an accurate description is given of
the compounds which were formed, and of the proportions of
their constituents. The ot/y substance became saponified more
readily than the fatty substance; the residual fluids in both cases
contained the sweet oily principle; but the quantity that pro-
ceeded from the soap formed of the oily substance was four
or five times as much as that from the fatty substance; the
latter soap was found to contain a much greater proportion of
the pearly matter than the former, in the proportion of 7-5 to
2-9; the proportion of the fluid fat was the reverse, a greater
quantity of this being found in the soap formed from the oily
substance of the fat.
When the principles which constitute fat unite with potash, it
is probable that they experience a change in the proportion of
their elements; this change developes at least three bodies,
margarine, fluid fat, and the sweet principle; and it is remark-
able that it takes place without the absorption of any foreign
substance, or the disengagement of any of the elements which
are separated from each other. As this change is effected by
the intermedium of the alkali, we may conclude that the newly
formed principles must have a strong affinity for salifiable bases, ’
and will in many respects resemble the acids ; and, in fact, they
exhibit the leading characters of acids in reddening litmus, in
decomposing the alkaline carbonates to unite to their bases, and
in neutralizing the specific properties of the alkalies.
M. Chevreul’s Fourth Memoir.*
The subject of M. Chevreul’s fourth paper is the action of
certain salifiable bases upon hog’s-lard, and the capacities for
saturation of margarine and fluid fat. Having already pointed
out the analogy between the properties of acids and the prin-
ciples into which fat is converted by means of the alkalies, the
next object was to examine the action which other bases have
upon fat, and to observe the effect of water, and of the cohesive
force of the bases upon the process of saponification. The sub-
stances which the author subjected to experiment were soda,
the four alkaline earths, alumine, and the oxides of zinc, copper,
#* Abstracted from Ann. de Chim, xciv. 225.
1818.] their Combinations with Alkalies. 193
and lead. After giving a detail of the processes which he
employed with these substances respectively, he draws the
following general conclusions. Soda, barytes, strontian, lime,
the oxide of zinc, and the protoxide of lead, convert fat into
margarine, fluid fat, the sweet principle, the yellow colouring prin-
ciple, and the odorous principle, precisely in the same manner as
potash. Whatever be the base that has been employed, the
products of saponification always exist in the same relative
proportion. As the above-mentioned bases form with marga-
rine and the fluid fat compounds which are insoluble in water, it
follows that the action of this liquid, as a solvent of soap, is not
essential to the process of saponification. It is remarkable that
the oxides of zinc and of lead, which are insoluble in water, and
which produce compounds equally insoluble, should give the
same results with potash and soda, a circumstance which proves
that those oxides have a strong alkaline power. Although the
analogy of magnesia to the alkalies is, in other respects, so
striking, yet we find that it cannot convert fat into soap under
the same circumstances with the oxides of zinc and lead. But
although magnesia does not saponify fat, it forms with it an
homogenous substance, from which the fat does not separate
even when placed in boiling water, notwithstanding the differ-
ence in the specific gravity of the ingredients. Alumine that
has been mixed with fat is entirely separated from it by this
means. Hence we may establish three gradations in the action
of salifiable bases on fat, that in which a perfect saponification
is produced, as is the case with the alkalies, where there is a
union but not a proper saponification, as with magnesia,
and where there appears to be no union, as in the case of
alumine.
The author next proceeds to examine the quantity of fat which
a given weight of potash can saponify, in order to form a stan-
dard of comparison for the other saponaceous compounds, when
it was found that 100 parts of hog’s-lard were reduced to the
completely saponified state by 16°36 parts of potash. He now
enters upon the consideration of the different soaps that are
capable of being formed by the margarine and the fluid fat
respectively, and endeavours to estimate the proportions of which
they consist. The soap composed of margarine and potash, as
has been stated above, exists in two proportions, the saturated
compound, consisting of 100 parts of margarine to 17-77 of
potash; the other, or the super-margarate, consisting of 100
arts of margarine to only half the former quantity of potash,
‘8 parts. It is observed that in the first of these combinations
the margarine saturates a quantity of base, which contains three
parts of oxygen, proceeding upon the estimate that 100 parts of
potash contain 17 of oxygen. M. Chevreul then prepared
soaps composed of margarine and soda, margarine and barytes,
margarine and strontian, and margarine and lime ; by decom-
posing them by an acid, and finding the quantity of neutral or
* Vou, XII. N° III. N
194 M. Chevreul on Fatty Bodies, and (Serr.
earthy salt that was thus formed, he was able to estimate the
quantity of base that had been united with the margarine in each
of the compounds. These were found to be as follows :
Migeoruriie™ 6270). 5 ave ales 100-00
Byte. Sts aianvstete' suite eae PEN bi
Margarine ..... aie tied 100-00
Batytes: sctees avin siew a oies 28°93
Moarcarine: ois Qa 100-00
Strontian. ....... ite He 20°23
Margarine’ ..'. ones «sus 100-00
MAME: Se wre cin aia Wate lav wants
By calculating the amount of oxygen contained in these
different bases, it appears that in these compounds, as well as
in that of magarine and potash, the margarine unites to about
three per cent. of oxygen. By boiling margarine with the sub-
acetate of lead, a compound was formed of margarine and the
protoxide of lead, which consisted of 100 parts of margarine to
83-78 parts of the protoxide of lead ; but as this would contain
nearly six per cent. of oxygen, it was supposed to be a sub-soap,
or one with an under proportion of base. By boiling together
the saturated solutions of nitrate of lead and soap of potash, a
neutral compound of margarine and oxide of lead was procured,
composed of margarine 100 parts, and 41°73 parts of oxide of
lead; the oxygen in this quantity of oxide of lead is 2-98.
M. Chevreul next proceeds to examine the compounds formed
by the union of the fluid fat with the different bases. It was
found more difficult to ascertain the composition of these soaps
than of the soaps of margarine, because it was less easy to pro-
cure the fluid fat in a uniform state, always exhibiting the same
properties ; under one form in which it was procured it remained
fluid almost to the freezing poimt of water, while another spe-
cimen congealed at 43°. The soap of the fluid fat and barytes
was found to consist of fluid fat 100 parts, and barytes about
27 parts, which will give 2°83 per cent. of oxygen in the com-
povnd. The soap of fluid fat and strontian consists.of 100 parts of
the fluid fat to 19-38 of strontian, containing 2°81 parts of oxygen ;
and the soap of the fluid fat and the protoxide of lead may be
estimated at about 100 parts of the fluid fat to 114-81 of the
oxide of lead. There was some difficulty in estimating the
composition of the soap of the fluid fat and potash, in conse-
quence of the tendency which these bodies have to form a
super-soap as well as a neutral soap; but by a careful, synthe-
tical experiment, the author~ascertained the proportion of the
constituents to be 100 parts of the fluid fat to 16°58 of the base ;
this quantity of base contains 2°82 parts of potash. The scap
of the fluid fat and soda consists of 10°11 parts of alkali to 100
parts of fat. M. Chevreul then states the composition of some
of the other saponaceous compounds formed by the fluid fat;
1818.] their Combinations with Alkalis. 195
with lime it combines in the proportion of 100 parts to 9-64;
with magnesia, 7°52; with oxide of zinc, 14°83 ; with peroxide
of copper, 13-93 ; the soap of copper was of a green colour; as
was also the case with the soap composed of the black peroxide
of copper and margarine. Soaps were also formed of the fluid
fat with the oxide of cobalt, which was of a bluish green
colour; with the oxide of nickel, of a yellowish green; and with
oxide of chrome, which was of a violet colour: in these last
cases the exact proportions in which the substances combine
were not.ascertained. The above experiments establish in a
decided manner the strong analogy which exists between mar-
garine and the fluid fat and acids ; they have, like these bodies,
determined capacities for saturation, while their combinations
with salifiable bases may be regarded as forming a distinct class
of salts. The art of making soap consists, therefore, in convert-
ing fatty bodies into oily acids by means of alkalies; and in
forming these acids into compounds subjected to definite pro-
portions.
M. Chevreul’s Fifth Memoir *
The subject of this memoir is adipocire; by which is meant
the crystallized substance that enters into the composition of
human, biliary calculi, spermaceti, and the peculiar matter
obtained from dead bodies. The term adipocire was introduced
by Fourcroy, and was applied by him to the three substances
mentioned above, which he conceived to be varieties only of the
same primary compound ; and in the latter case, as obtained
from the muscular parts of animals that had experienced a pecu-
liar change in the earth to be converted into the state of a soap
by the addition of ammonia. These opinions of Fourcroy,
however, M. Chevreul supposes to be erroneous. He begins by
examining the crystallized matter of human, biliary calculi; the
properties of this substance are described; it melts at about
278°, and crystallizes by cooling into radiated plates; it
appeared to be only partially decomposed by distillation ; it is
readily dissolved by boiling alcohol, but it seemed to be inca-
pable of forming a soap with potash,
The properties of spermaceti are next examined; it melts
at about 112°; it is not much altered by distillation ; it dissolves
readily in alcohol, but separates as the fluid cools; the solution
has no effect in changing the colour of the tincture of litmus, a
circumstance, as it is observed, in which it differs from marga-
rine, a substance which, in many respects, it resembles. Sperm-
aceti 1s capable of being saponified by potash, with nearly the
same phenomena as when we submit hog’s-lard to the action of
potash, although the operation is effected with more difficulty,
® Abstracted from Ann. de Chim, xcv. 1,
Nn 2
196 M. Chevreul on Fatty Bodies, and [Serr.
For the purpose of analyzing the soap, it was added to a large
quantity of water, and kept at the temperature of 212°; it was
not dissolved; but the fluid, as it cooled, deposited a large quan-
tity of opaque flakes. A portion was kept suspended, which
had a brilliant and pearl-like appearance ; this was collected,
and dissolved in boiling alcohol, from which it was in part depo-
sited by the cooling of the fluid: this was the proper soap
formed of spermaceti and potash. This soap, after being
properly purified, was decomposed by muriatic acid, when it was
found to be composed of a peculiar fatty substance, to which
M. Chevreul gives the name of saponified spermaceti and potash,
in the following proportions :
Saponified spermaceti. .. 92°462 ...... ..«- 100:00
BOCAS nara a Bin. Bfereiatn.c) sta WOOD Wiel ove ouhla 9 wane AP Ko
The soap of spermaceti is white, and is without taste. Alco-
‘hol, which has been saturated with it at the boiling heat,
concretes into a mass as it cools; the solution slightly reddens
hematine, but has no action upon litmus, in which respect it
differs considerably from the super-soap of margarine. The soa
of spermaceti is insoluble in water; but if it be boiled for a long
time in this fluid, a quantity of the alkali is separated from it.
The soap itself, by this process, appears to be decomposed into
two compounds containing different proportions of potash ; one,
5:48 parts of potash ; and the other, four parts to 100 parts of the
saponified spermaceti.
M. Chevreul then examined the properties of the saponified
spermaceti ; its melting point is the same with pure spermaceti,
but it is more soluble in alcohol ; the solution reddens litmus ;
and, as it cools, concretes into a crystalline mass ; it is capable
of being combined with an additional quantity of potash, so as
to form a soap similar to that described above. The authornext
enters into a minute analysis of the substances which are con-
nected with the saponified spermaceti in the process by which it
is formed; he supposes them to be as follows: 1. Saponified
spermaceti; 2. An oil which is fluid at the ordinary temperature
of the atmosphere ; 3. A concrete oily substance; 4. A yellow
matter ; and, 5. A volatile oil: but it is admitted that the last
four bodies exist in so small quantity as to render it difficult to
ascertain their properties with accuracy. It is supposed that the
third substance is a combination of the first two; and that it is
particularly to the second that it owes its property of being
soluble in potash. “MI. Chevreul remarks that the air may have
had »some effect upon these substances, particularly upon
the fourth and fifth ; for that the experiments occupied more
than six months, during which time they were continually
exposed to the air. Saponified spermaceti is very analogous to
margarine; but this substance is sufficiently distinct from sper-
1818.] their Combinations with Alkales. 197
maceti both in its pure and in its saponified state; They differ
materially in their boiling point, in their solubility in alcohol,
and in their capacity of saturation with potash. _
We next proceed to the third part of the memoir, an account
of the fatty matter occasionally formed in dead bodies. We
have an examination of the substances which are united to the
fatty matter, and afterwards an analysis of the fatty matter
itself. The fatty matter was first acted upon by alcohol, and
afterwards the residte, insoluble in alcohol, was boiled with water.
The water removed small portions of lactic acid, lactate of lime,
lactate of potash, a yellow colouring matter, and an azotated
matter. The substance which was insoluble in water was then
treated with muriatic acid,.and the fluid was saturated with
ammonia, when phosphate of lime and magnesia, and oxide of
iron were deposited: by the addition of carbonate of ammonia,
carbonate of lime was deposited. The part which was insoluble -
im muriatic acid was again treated with boiling alcohol, by which
nearly the whole of it was now dissolved, except a small quan-
tity of an azotated matter and some extraneous substances.
That part of the fatty matter which had been deposited from
boiling alcohol was then examined; it melted at 175°; by pro-
longing the fusion, ammonia was diséngaged, and the substance
was rendered more fusible. The substance was decomposed by
muriatic acid; and from the result of the process, we learn that
it consisted of a peculiar fatty matter, to be afterwards more
particularly examined, ammonia, potash, and a minute quantity
of lime which were combined with it. The alcohol itself was
then examined, when by gradually evaporating it, two distinct
substances were separated from it, which differed a little in
their melting point and other properties, chemical and physical.
A portion of ammonia, together with lactic acid and some other
substances in small quantities, were detected in the fluid. The
author’s general conclusion respecting the fatty matter of dead
bodies is that, even after the lactic acid, the lactates, and other
imgredients which are less essential, are removed from it, it is
not a simple, ammoniacal soap, but a combination of various
fatty substances with ammonia, potash, and lime. The fatty
substances which were separated from alcohol, as has been
remarked above, had different melting poimts and different
sensible properties. It follows from M. Chevreul’s experiments,
that the substance which is the least fusible has more affinity
for bases than those which are more so. It is observed that
adipocire possesses the characters of a saponified fat; it is
soluble in boiling alcohol in all proportions, reddens litmus, and
unites readily to potash, not only without losing its weight, but
without having its fusibility or other properties changed.
As adipocire appears to exist in different states, or as the
same term has been applied to substances possessed of different
properties, the author examined the action of potash upon
198 M. Chevreul on Fatty Bodies, and [Sepr.
different varieties of it, and first upon adipocire that is fusible
at 113°. He saponified 60 parts of this adipocire by half its
weight of potash dissolved in water ; the soap that was formed
was soft and opaque; a mother-water was left of an orange
colour. The soap was diluted with cold water, when 40 parts
of the pearl-like matter were extracted from it; what remained
in solution being decomposed by tartaric acid, 16 parts of a
reddish matter were procured, and 1°5 of a white, flocculent
matter. The mother-water was then examined ; by distillation
4 quantity of ammoniac and an oily matter were obtained, and
by using different re-agents, an odorous principle, and a bitter,
yellow matter were also procured; by analyzing the pearly
matter of the soap of adipocire, this body was found to consist
of margarine, of a fatty matter which is fluid at 44-5°, of a yellow,
colourimg principle, and of an odoriferous principle. An adipo-
cire which is fusible at 129° was then subjected to the same
series of operations with the preceding, when it was found to
contain the same principles, but in different proportions; it dif-
fered especially in containing more margarme than the former.
The author then compares the margarine of the fatty matter
from dead bodies with that from the soap of hog’s-lard. They
are both soluble in the same proportions in boiling alcohol; the
solutious both of them redden litmus, and deposit brilliant crys-
tals as they cool. They are similarly affected by heat, they
combine with potash in the same proportions, and they form
soaps which exhibit very nearly the same properties. The
points in which they differ are their fusibility, and the form
which they assume when they pass from the fluid to the solid
state ; but these differences are not considerable, and, perhaps,
are not sufficient to induce us to regard the substances as essen-
tially dissimilar.
In his third memoir, M. Chevreul has shown, that hog’s-lard,
in its natural state, has not the property of combining with
alkalies ; but that it acquires it by experiencing some change in
the proportion of its elements. This change being induced by
the action of the alkali, it follows that the bodies of the new
formation must have a decided affinity for the species of body
which has determined it. If we apply this foundation of the
theory of saponification to the change into fat, which bodies
buried in the earth experience, we shall find that it explains the
process in a very satisfactory manner. In reality, the fatty
matter is the combination of the two adipose substances with
ammonia, lime, and potash; one of these substances has the
same sensible properties with margarine procured from the soap
of hog’s-lard; the other, the orange-coloured oil, excepting its
colour, appears to have a strong analogy with the fluid fat.
From these circumstances it is probable that the formation of the
fatty matter may be the result of a proper saponification produced
by ammonia, proceeding from the decomposition of the muscle,
1818.] their Combinations with Alkales. 199
and by the potash and lime, which proceed from the decompo-
sition of certain salts. Two suggestions are offered by the
author, which seem to result from his conclusions, although
_they are in opposition to the opinions generally received on this
subject, and which he proposes to make the subject of a future
memoir. He asks, whether fat is not the only animal matter
which is capable of being converted into the peculiar adipose
matter, and not the muscular fibre? and must not this change
be effected by alkalies, and not, as is generally supposed, by
nitric acid ?
The author concludes by giving a summary view of the differ-
ences between the three bodies which have obtained the name
of adipocire. The biliary calculus and spermaceti may be con-
sidered as immediate simple principles, since we have not been
able to separate any bodies from them, without changing their
nature. But this is not the case with adipocire, properly so
called, as this certainly results from the action of two fatty
bodies, one of which has the greatest analogy with margarine,
while the other is very similar to the fluid fat. Biliary calculus
requires for its fusion a temperature of 278°, whilst spermaceti
melts at 112°. The fatty matter from dead bodies melts at
different temperatures, from 111° to 129°, according to the pro-
portions of the substances that enter into its composition, One
hundred parts of boiling alcohol dissolve 18 parts of biliary
calculus, and 6:9 parts of spermaceti: adipocire appears to
dissolve in it in an indefinite quantity.
Potash boiled during 15 days with biliary calculus in the
proportion of five to one does not saponify it. The same alkali
boiled with spermaceti during five days in the proportion of 18
to 30 entirely saponifies it. A substance is then produced ana-
logous to margarine, but which differs from it so decidedly in
some respects, that they may be considered as forming two
distinct species. If the difficulty of saponifying biliary calculus
does not depend entirely upon its force of cohesion; if, for
example, we should prove that it cannot be effected by exposing
it ina digester to a temperature of above 280°, we must conclude
that the proportion of the elements of biliary calculus does not
admit of its being reduced into the state of a body which has a
great affinity for alkalies. The difficulty which there is in sapo-
nifying spermaceti shows that the elements of it are not in the
same relation as those of fat; and what proves the same thing is,
that spermaceti does not produce the sweet principle of oils, as is
the case with fat.
(To be continued.)
200 Mr. Heuland on a Mass of Platinum. [Serr.
ARTICLE VI.
On a Mass of Platinum at Madrid. By Henry Heuland, Esq.
(To Dr. Bostock.)
DEAR SIR, 25, King-street, St. James's, July 22, 1818.
I sec to wait upon you with the extract from an authentic
communication, with which I have been favoured, respecting
the mass of platina now deposited in the Royal Museum at
Madrid. Dn. ignaico Hurtado is the proprietor of certain lands
in the Quebrada* de Apoté, in the province of Notiva, in the
government of Chocd. In this Quebrada is situated his gold
mine, called Condoto. One of his negro slaves, named Justo,
found this mass of platina in the year 1814, near the gold mine.
Dn. Ignaico, most generously, and full of ardour for the sciences,
resented this unequalled specimen to His Most Catholic
Tajesty, through his Excellency Sor. Dn. Pablo Morillo, Com-
mander-in-Chief of the Royal Spanish armies in the province of
Venezuela, who transmitted the same, together with other
objects of natural history, belonging to the botanical department,
under the Spanish naturalist Dn. José Mutis, to Europe through
General Pascual Enrile, who brought it safely to Sant and
forwarded it to the hands of the King himself by Captain Antonio
Van Halen. Being an unique specimen, his Majesty gave it to
the Museum. Its figure is oval, and inclining toconvex. The
Spaniards term it “ Pepita,” which signifies water worn, and not
in sitt.
Its larger diameter is two inches, four lines and a half; and its
smaller diameter two inches. Its height is four inches and four
lines. Its weight is one pound, nine ounces, and one drachm. Its
colour is that of native silver. Its surface is rough, and here
and there spotted with yellow iron ochre. The negro who found
it suspected that it contained gold: he tried to fracture it, but he
was only able to make a dent in the metal, which is, however,
sufficient to show its character.
I have to note the very important discovery of two mines of
precious opal in the kinedom of Mexico ; they are in the district
of Gracias de Dios, 60 Spanish miles in the interior of the pro-
vince of Honduras, or Comayagua, in the kingdom of Guati-
mala. These opals are imbedded in porcelain earth, and are
accompanied by all the other varieties of opal, but particularly
by the beautiful sky blue girasol, and by the sun opal of Son-
nenschmidt, who discovered the latter at Guadalupe at a
league’s distance from Mexico, the capital of that name. The
gentleman through whom I procured these opals, presented to
; Quebrada signifies 2 country broken into, or intersected with ravines and
clefts.
1818.] M. Proust’s Analysis of Barley. 201
me a very interesting meteorite, not yet described in any work;
it is from the coast of Omoa, in the province of Honduras, at
10 leagues’ distance from the sea, and was found on a hill which
abounds with this iron. The history of its fall and dates are
‘unknown.
To avoid every possible doubt about the mass of platina, I
should, perhaps, have mentioned, that the Spanish Secretary
of State, his Excellency Dn. José Garcia de Leon and Pizarro,
had taken all the measures to ascertain the fact of its bemg
genuine, native platina.
I have the honour to be, dear Sir,
Your most obedient and humble servant,
Henry HEvULAND.
Articie VII.
Analysis of Barley. By M. Proust.
Bar.ey has been made the subject of an elaborate chemical
analysis by MM. Fourcroy and Vauquelin, and by M. Ennhof,
who each of them published his remarks upon it about the same
period. The latter of these chemists found ripe barley to con-
tain starch, sugar, mucilage, gluten, albumen, a minute quantity
of phosphate of lime, and a considerable proportion of a volatile
matter, the nature of which appears to be not very accurately
ascertained, besides the woody fibres which enter into the com-
position of the husk. To these constituents Fourcroy and Vau-
quelin have added a peculiar species of oil, which was procured by
macerating the barley meal in aicohol; the fluid, by this process,
becomes muddy, acquires a yellow colour, and deposits the oil
by evaporation. They also detected in barley minute portions
of some earthy neutral salts, and of iron, which were not men-
tioned by Einhof. This substance has been also examined by
M. Proust, and his account of it differs considerably from that
of his predecessors: it would appear from his statement that his
experiments were principally performed some years since, even
anterior to those referred to above, although they were only pub-
lished during the last summer.*
Alcohol extracts from barley a yellow resin, which, when dry,
has a pitchy consistence, and is not soluble in water. It exists
likewise both in wheat and in maize, and is found in them all in
the ta Aig of about 1. of their weight ; it is not destroyed
by the process of germination. When barley meal is washed
with cold water, we procure a yellow saccharine extract which
is readily decomposed by alcohol; it seems to consist of gun,
* Ann, de Chim, et Phys. vy. 387, (Aug. 1817.)
5
202 M. Proust’s Anaiysis of Barley. [Szert,
sugar, and gluten, in the proportions of -04, -05, and 03 respect-
ively. The author remarks, that these sums, making in the
whole 12, areexactly the quantity of loss which M. Sage found
wheat to experience by being treated with cold water.
But besides these products, M. Proust informs us that he has
discovered in barley a large quantity of a new principle, which
had hitherto been confounded with starch, and which is pro-
eured by washing the meal in the same manner as when we
wish to obtain gluten ; but instead of this substance, we perceive
on the fingers a rough, gritty matter, which is the body in ques-
tion. M. Proust givesit the name of hordeine.
This hordeine, or hordein, is not soluble in water, and may be
separated from the starch by boiling ; it will then be left in the
form of a yellow, granulated powder, which, he says, from its
appearance, might be taken for sawdust. The following are the
} —- =
2 YP. 08 (y BAL 2b
By making m = 4,n = 2,a=c, and P = —1; in formula A.
bae™—1dx
Fluent 13.—Required the fluent of Vane
,
b22°—1lder
Paste OS aaa fey
_ 2bx n\ 2° Q2ab ne1 n\ — i
Se (a ee Se ao 'dz(a+ fa")?
[26 x ee 77 n\i
= amc Ge cee
The same as Mr. Dealtry’s when reduced; m = n, &c. in
formula A.
1818.) Lacroix’s Differential and Integral Calculus. 207
edz
Fluent 17 —Required the fluent of 7===-
This fluent being of the same form as fluent 13, it may be
compared therewith ; by making 2x — 1 = 3, orn=2,a= 2°,
fet, and f.=.1.
weder z2—@
Then ee =
Dealtry’s when reduced.
‘Fluent 20. (Case 4.)—Required the fluent of ra
a
(a? + 2°)2 ; the same as Mr.
Pay
By comparing with fluent 13; wehave22—1=1, orx=
2. Bey dae dod Gees
zrdx am pascal BSREBL SN
Then == = Bee “/x— a; the same as Mr.
Dealtry’s when reduced.
Fluent 23. (Case 2.)\—Given the fluent of sl ase re-
J2ax+ x2”
as
Se
V Zax + x?
Dias
SSS eee wdx 2 2)~ 3
VY 2axn+ 2 wie ( G2 ict!) z
3
= [x drQat at
& vx (2a + 2)3 —3afaedz(Qa+ 2)-%
Fee a ue Ba TT
= r(Qax+ 22 ape. oN ees ae
2 2 Qax+ x2
By comparing with formula A, m = 3,n=1,a=2a,b=
1, andP = — 1.
Fluent 28 Given the fluent of (a + ¢ 2")" .d2"~' dz; to find
the fluent of (a + ca")™".d 2" dz.
ee d z(a +c z")™
ae (a + ext )™t+t— an frn—s dz(a+ez2)m
quired the fluent of
cn(r + 2)
am(a+cm)jm+t ad
SS ee ,t—™e_"ERE n—1 \m.
en + (r + 2) c(ur+2)Jf * dz(a+c2z)".
The same as Mr. Dealtry’s, when L is put instead, of
(a+cem)™,, xd
(m+l)ne
is written form, c for b, and m for p.
Fluent 31.—Given the fluent of 2"*-" dz (a + c2*)"; to find
the fluent of 2"-"-* dz (a + ¢ 2").
In making the comparison for this fluent, 2
208 Mr. Adams on [Sepr,
et dz(a+ezy" =
are—e(a tice ett — (m + r)nefarn—tde (a + C2 )™
ahG ajo ee et
where m =rn—n, P = m, and b =c; in formula C.
Fluent 32.—Given the fluent of 2°"*"—' dz (a + c 2°)"; to
find the fluent of 2°"~'dz(a + c2""*',
af a d24a ie 2S =
wn (a+ ex ymtt —on(m +1) fornte-idz (at cz")
———
rn
This fluent belongs to formula E, where m = rn+n,b6=c,
and P= an:
Fluent 33.—Given the fluent of 2"~-"-'dz(a + 2")"; to
find the fluent of z""~' dz (@ + c2")"".
See Ce ME C2.
Ps
arn—-1 (a + ca ym — (rn—n) f2rm—n—dz(a + cz" jm
Eee Pe eS ee Ae eS ee ee
mnc
This fluent belongs to formula F; where m = rn, b = c, and
P =m. f
Fluent 38.—Given /°2" dz(atc2"=G
Required /27** dz(a+c2y"=H
fe erds (a + ey”
i dz (a ef Cc 0) — K
&e.
This class belongs to formula A.
And fx dz (a +2") eee
frdza +ezryr?=M
fez oye? =
&e.
This class belongs to formula B. .
From whence
gti(atecm)™t+! —afr +1). G
4 =
cimn+n+r+ 1)
wtnti(a + emt )m™+1—a(r+n+ 1). H
je ee ae a ee a ee
c(mn + 2n+7r + 1)
1818.] Lacroix’s Differential and Integral Calculus. 209
tentt (a+ co )mt+t—a(r+2n41).1
Ke c(mn+3nt+r-+ 1)
&e.
Where r is continually increased by x.
And
nS wti(a+com)mt+1+ (m+ l)na.G
mn+n+rd¢1
M = w@t+ifa+cm)m+2 4 (m + 2)na.
mn+2n+rt+1
N= wt(at+ com)™+3 + (m+ 3)na.M
mn+3n+r+1
Xe.
Where m is continually increased by unity.
ArTictE IX. ,
Account of the Weather at Bombay.
(To Arthur Aikin, Esq.)
DEAR SIR, Foster-lane, May 28, 1818.
Tue inclosed register of the weather at Byculla, Bombay,
has been transmitted to me by Mr. Benjamin Hoton of that
settlement. If you think it will be interesting to the readers of
the Annals of Philosophy, it is much at your service for that
purpose. Yours truly,
RicHARD KNIGHT.
Annual Statement of the Observations on the Weather, made at
the Rooms of the Literary Society of Bombay from July,
1816, to June, 1817.
eae THERMOMETER, BARoMETER.
Mean. | Highest. | Lowest. |} Mean. | Highest. | Lowest.
1816, nches, | Inches, Inches.
BENE site's 222)" - 80° 84° 119 29-80 29°89 29°64
August. ...... 184 814 764 29-82 29-99 29°71
September.... 794 824 15 29°905 30-04 29-79
October......) 833 87 80 30-035 30°19 29-95
November .... $24 864 18% 30:07 30:19 29-96
rrebe evo TOR 83% 16 30°075 | 30°18 30°01)
January ...... 783. 83 A 30-135 80°19 80°01
February. .... 16% 82 10 30°10 30°22 29-96"
March eceescan 19 82% 15 30-065 30°19 30-01
oT, | ee 83h. 884 80 29-99 30°12 29-94
BABY soc deus ew 85 90 82) 29°95 30°09 29°76
DUNE. oc cccks 82 49 “i } 29°885 29°99 29°62
Vou, XII. N° II, O
210 Account of the Weather at Bombay. [Szrr.
N.B. The temperature is taken at 10 a.m., 1 p.m., and
4 p.m., daily; consequently the register does not show the
extreme of cold, nor the true mean, which is probably about 2°
lower. ;
The pressure is taken at 10a.m., and 4 p.m., daily, at the
opening and closing of the rooms. :
Sag
A Register of the Quantity of Rain fallen at Byculla, Bombay
inthe Months of June ph July, 117. ~ :
Inches, Inches.
June 1 beste cle cok tem July 1 ...cccceeees 0:09
oe'w wp oleate. ale ena Pod NWCA Ne aS vier aielen 0-49
OP his syplin aha leas — + renee SMe ae i 0-05
ME Ge'tectoisersicy sori bree aid he sisal ae 0°18
a Ae rar 6°46 Re iss awate are :
6 @eseeeeerevanend pes! 6 eecevreeereeeioe 0 27
Mattes tia eine Cae 0°03 RR ear” 0°15
Trams eacla sete e.alt 0:11 a ceelen earewat oes
eit fase aint nm DU SE eee i 0°55
ED i sever ariseein’ Feu a eine d te iiseraee 2:06
RA cnn eect anes 1°57 MID va eleleg estes 0°17
REA Bese 0:20 1D iin wien ale 3°80
13 Re ee ge! oe 2°30 | ASAP eS 0-99
abs ees 1:03 Le ae ey ic pare: 1°34
15 eeeereoecee =r 15 eoesosseesee 2°57
167 Soe ee 0-16 | NG) iowa as mcesmintett 3°00
WES AT te 1:38 iss eee 0-49
LS a alas « pintowie oe O12 DS is Lamon auleeiee 0°35
DOT See anes 1°85 BO ems watt ele Beg Be |
DOr ca span wanes 0-54 yee lye Kembla 0-20
BET aeons meee _— OD Samy eee occa 0°25
Be Say eee Wane “hia D9! Se Lae 0-08
Se Saaie ne stacalbia’ © 9°03 Bet (a ticheentaets wee 0°35
Bi rhshe: late uvieliaars's 7°23 OA igranatace wraierwatet 0-43
25 Mfatalnte = sis 0-15 BOW les «cele ee as 0°64
26 oa esas O73 2) ee a con: CAGE
27 e @eoesece . ae 27 ecesesee eeee eae
Or cpemmnb sa ws) [Orae 0. bss peboabian on 0°42
OO) cals Sines a Ba pela Oa aie ss spread 0-06
30 e@eeceeees sees 1:15 30 eoeeseseeeres 0°13
— PMMA Ge oe aay 31 exoeeerereeece 0:15
"ROU PAGES oh nsiavece 40578: | Rota siecle ives ewes «1 23°87
SCANT RO” SE 45:72
PEGs eins snsie.o's « ieidla's <4 0d 23°87
Be 5 eA 69°59
1818.} Account of the Weather at Bombay. 211
The pluviameter is fixed about three feet from the ground
in an open garden, and the time of observation is 7 a. m.
daily.
The greatest quantity of rain in one day in June was on the
23d, viz. 9:3 inch. But on the 24th the rain was the heaviest,
and is particularly. worthy of remark. It commenced about
8 a.m., and discontinued about 5 p.m.; so that the 7:23
inch. of rain fell in nine hours. Greatest quantity in July, on
the 12th, 3-80 inch.
August 1, 1817.
i
Register of the Quantity of Rain fallen at Byculla, Bombay,
in the Month of suhadec 1817.
Inches
Best: 1: va, ek ket i ooh s Pe Sr 0-04
Be Ce oEaaca ahs Bc di: vkontere! s/atvhere ai —
OE Aas RR anata Seek Ber 09
AY ae bi haa Oe sis, wialiavecotecaliase 0-18
ce ONS IS SITE As abe 0:07
POC CO EE CORE See ec 0:02
Ti atl whee Pee SNS AS Se Be 1:33
BW Ste aes set ph oa ae fei nia lacae Ar 0°33
Pir: shetere cc sipteigharate'ste araleleres and per Oe
Discs neo’ Reiolanais ated, 6 sevse O92
eee ORE Ack slave ole « ca vate Ore
De eitehie sisis(ab cela Sapaubrealts 32 1:50
La ee a ayavaiie acecaevetene .. 408
r BFReg od A pioih alee Nick dig sinlipi whole aparsie cenporae
15 cis. Sle bt prasa wie besle: aire = pe Lae
BOS svete eee syhi aia si ajatele, dra RO
Gi cae, 3, eee aN 0-42
MEd eran ct atlas dapat 3. as’? OF40
Sr eee Me tea Lp) 1-09
21 eCoeeeeoesesrer egeese eevee 1:75 P
22 ea eeeeeoeoeosee teen eeasesens 1:58
ee ei de: Sr eat te
4 SEE 6.9 oinsn winsoiaoidiaw'aincotinieeralnk aig Ole?
25 Coe oer eeoeeseerereeeseres =
POLS 6 om cing Galavud Vee ae Vite
27 ereeeeoeeeeeeeeenesreeeses 0:21
28 eeeseoe coe eeeereseseseeee 0°55
30 Maile #ele/ee sislelele é)s's alure se steece 1-50
Total . Peewee eroresreseeseeoeeeese 24°87
o 2
212 Mr.. Gill on the New Improvements in the [SzEpr-
Total in June. LRT SE HE EES 45:72
Fudge PA Aas ae eek. ea OF
ATIBUBE. > c's alot «Ga ane ne Oe
Reel lits SO OeT Gy Beye
ee
Total for the four months ..........403°80
Oete dk oy op te sshd eb ecetaononee
Total . Scat CV piaratal thariainive, ate pjai’e'ya: 32’ 30” Mean Time at Bushey.
Batellite y cia o.'csi deo -iopicieleie 9 33 51 Mean Time at Greenwich.
15, Immersion of Jupiter’s second re 27 21 Mean Time at Bushey.
satelbite .. «2 werdereis estes 28 42 Mean Time at Greenwich.
15. Emersion of Jupiter’s third ye 52 13 Mean Time at Bushey.
satellite. eisialbere eee oe 53 34 Mean Time at Greenwich,
23, Emersion of Jupiter's first rant 15 54 Mean Time at Bushey.
BROMUS one Sew iaibuted cess 17 17 Mean Time at Greenwich,
Magnetical Oitemvanous SN 1818. — Variation West.
Morning Observ. Noon Obsery. Evening Obsery.
Month.
Hour. | Variation. Hour. Variation. Hour. | Variation.
July 1) 8h 25’) 240 32’ 21” 1 30’| 24° 45' 99" Th 25’) 24° 36’ 567
2| 8 25); 24 33 52 1 25 | 24 49 34 T 55.) 24 30. 58
3} 8 39] 24 35 49 1 25} 24 44 18 1 35 | 24 38 30
4| 8 25} 24 “31 24 1 30] 24 45 30} 7 30) 24 39 35
5} 8 30}; 24 32 58 1 40 | 24 44 55 7 40 | 24 37 48
6)> 8" 5 [P24 Sb. is 1 30|24 46 39 7 35 | 24 38 14
T} 8°35 1 24°" 33 +23 1 25 | 24 44 49 7 35 | 24 38 OS
8]°.8, 25} 24 3234 1 30] 24 43 48 7 30)24 38 29°
9{| 8 30] 24 34 O09 1 3b 28 LT 16 7 30; 24 39 02
10] 8 30| 24 34 45 1 30}; 24 47 40 1 35)) 24" 38.57
Il Br 2b) 245732 716 1 35 ]24 43 51 % 35 24) $8. 39
lg2j— —{|— — — 1 25|24 43 44;— —|— — —
13| 8 30124 35 0;— —|— — — 7 30|24 89 O9
14]. 8 35 | 24 35 37% 1 30| 24 42 58 7 35 |24 39 30
15} 8 30{ 24 37 O82 1 25] 24 46 43 7 30) 24 37 52
16; 8 30}24 33 15 1} 15 | 24 44 19} — —|;— — —
17{j 8 25|24 385 03 1 20| 24 46 26} 7 35 | 24 37 57
18} 8 30 | 24 35 47 1 30] 24 43 19 7 30); 24 38 O7
19 BwvS5 es 33 4S 1 10) 24 45 36 7 20| 24 37 31
20} 8 30 | 24 37 40 1 20} 24 45 03 7 30|24 38 46
21 § (30) ) 24), 35,14 1 20)24 45 Ik} — —j|— — —
22} 8 830; 24 33 44 1] 25 |24 46 13 % 30. \24 37 36
23; 8 30)24 34 57 P2524 TAT POL 7 30} 24 41 OF
24; 8 30|]24 34 24 1} 25 | 24 42 58 7 10) 24 38 36
25. -&).25 124, Sha 13 1 35 | 24 44 45) KT ) 854|0QA 37.02
296; 8 $0; 24 33 40 1 30| 24 44 O1 7 30|24 38 38
27 8 35 | 24 34 38 1 55/24 42 43);— —/— — &—
98! 8 25/24 35 00 1 25) 24 45 58 1 25 | 24 35 .54
29; 8 30) 24 34 56 Ty 255) Bao vd Syed 7 25 |.24 38 15
30; 8S 30|24 35 30 1 25 | 24 44 26 7325. 172k AG an
31| 8 25) 24 32 29; 1 15/24 45 50);— —/}— — —
Mean for? ¢ o9| 94 34 24/1 1 97/94 44 59| 7 30/24 38 14
Month, ,
ee ee ee
1818.] and Meteorological Observations. 237
Meteorological Observations.
Month.) Time. | Barom. | Ther.| Hyg.| Wind. Velocity. Weather.| Six’s.
July Inches. Feet.
Morn....| 29°730 66° |} 42° WNW Fine 57®
1 <{Noon....| 29-683 13 32 WwW — |Cloudy 75
Even ....) 29°630 | 68 | 37 N Cloudy 58,
Morn,...| 29°640 | 62 40 E Fine t 3
2 <(Noon,...| 29-667 69 33 ESE — {Cloudy | “71
Even....| 29-700 | 61 | 38 SE Cloudy |?
Morn....| 29°768 | 60 | 43 sw Very fiuel 5 928
3< |Noon,...| 29°755 ve 23 WwW _— Fine 13
Even ,...| 29°720 €0 28 Nby W Cloudy t 59
Morn....| 29°652 60 43 NW Cloudy
42 \Noon....} 29°663 68 36 NW — |Cloudy 7
Even ....} 29°645 66 35 NW Fine 55
Morn....| 29°648 | 65 | 44 | NNW Cloudy ‘
of Noon....{ 29°638 | 71 34 N — /|Fiac 123
Even ....{ 29640 | 67 37 NW Fine 236
Morn.....} 29°668 66 43 NE Very fine ‘
6¢ |Noon....| 29°675 | 74 31 Var. — |Misty 79
Even....| 29°660 69 38 SSE Fine 5
Morn....} 29565 | 66 | 41 | SEbyS Fine t .
74 \Noon,...} 29°530 16 31 Var, — /|Fine 13
Even....| 29-460 | 66 38 Var. Cloudy 56
Morn,...| 29°432 62 44 W by N Cloudy ;
%< |Noon....} 29-463 67 32 | NWbyN — /|Fine ve
= AG ee a 64 31 NNW | Fine ‘ 5a
\Mern,...| 29°676 60 40 NNW Very fine
94 |Noon....| 29-700 | 71 QT NNW — |Fine 72
Even ....j 29°700 | 66 36 Calm Cloudy 64
/Morn....| 29°670 | 64 | 36 sw Fine f
109 Noon,...| 29-635 | 70 34 Wobys — |Fine 72
jEven ....| 29-600 65 AT Ss Cloudy
Morn....| 29-548 | 64 | 32 | NW Cloudy ' =
114 |Noon....] 29-515 | 72 | 29 Var. — |Cloudy | 73
iEven....4 29-470 66 37 WNW Cloudy ‘
‘Morn... | 29-373 | — | 75 N Rea ‘ 6a
124 |Noon....| 29-367 | 71 | 44 |NWbyN| — |otoudy | 71g
-|Even.. _ -~ _— _ eu ‘
)|Morn....| 29468 | 64 | 58 Ww Suniieite t 58
ce) \Noon.. i Seay See My mes on 135
\Even....| 29°643 | 67 | 42 | NNW Wery dual?
aa ‘Morn... .| 29-790 64 49° | NW by N Very fine §
Ncou....| 29:818 15 84 Var. — Very fine! 79
Even... .}| 29-820 73 39 Calm Lightshowers
ere ...| 29900 | 68 | 45 | NEbyE Very fine|{ 8
159 |Noon....| 29877 | 73 | 32 NNE — |Very fine] 7
Even ....] 29°875 12 A5 E Very fine
gd |Mora....| 29°844 | 70 | 44 Ww Fine f a:
169 |Noon....| 29-723 | 62 | 31 Var — {Fine 84
Even...) — ~— _ _ _
- 47) |Morn....) 29:763 | 69 | 44 | EbyN Cloudy ‘ 655
Noon....) 29°753 vel 44 Calm Showery | 76
Even....} 29°710 67 35 E Cloudy
{\Morn,...| 29-655 | 65 | 45 | ENE Fine ' 58
16) |Noon....] 29-605 Tz 35 ENE Cloudy 15
Liven....} 29°565 INE Cloudy
238 Col. Beaufoy’s Meteorological Observations. [Suv'r.
Meteorological Observations continued.
Month, | Time. | Barom,| Ther,| Hyg.} Wind. |Velocity.|Weather.|Six’s,
July Inches, Feet,
Morn..,.| 29°505 69° | 43° NE Fine 59®
19< |Noon....} 29-510 | 73 35 Calm — = [Much thund| 77
Even ....| 29°513 66 45 NW Showery 60
Morn,...| 29°523 64 52 N Cloudy
zo} Noon,,..| 29°556 | 72 38 NNW 3-787 |Fine TAL
Even,,..| 29°546 68 40 NNW Very fine 51
Morn... .| 29°532 62 43 WSW Fine
ai} Noon... .| 29°530 | 71 36 WbyS 5-856 |Cloudy 13
Even....) — — = — — 59
Morn,...| 29-620 66 46 Wbhys Cloudy
224 |Noon....| 29°673 75 31 Ww 7:826 |Fine 18
Even ....| 29°670 | 74 35 | SW by W Fine 60
Morn,...| 29°685 71 44 SE Very fine :
a3} Noon,...| 29°673 | 82 25 SE 4-231 |Very fine] 83%
Even ...| 29°600 13 33 E Very fine 66
Morn,...| 29°443 17 A2 ESE Fine
245 |Noon....| 29°438 | 88 21 SSW 7495 |Fine 895
Even ....| 29°437 83 23 SSW Thunder 653
Morn,...} 29°400 | 71 40 WSW Fine 93 ‘
95% |Noon....| 29°410 | 79 | 29 SSW | 11807 |Fine 19%
Even... .} 29°420 70 36 SW Fine 61
Morn,,..| 29°435 | 71 A2 SSE Fine :
28) Noon... .} 29°407 80 QT SSW 9°356 |Fine 81
Even....| 29°405 | 69 51 5 Showery : 64
Morn,...} 29°400 | 70 50 SSW Cloudy *
274 |Noon....| 29°420 62 55 WNW 5°313 |Thund.; rain) 76
Even... .| 29°533 _ 56 NNW Rain 51
Morn... .} 29°747 59 42» NW Very fine
284 |Noon....| 29°86 68 30 NNW 5°079 |Very fine} 70
Even....| 29°793 | 64 34 NW Very fine 5T
Morn,...} 29°800 64 AO SW Cloudy ;
294 |Noon....} 29.800 | 71 39 SW 5363 |Cloudy 12
Even ....| 29°780 | 68 AT Ww Fine ‘ 60
Morn... .| 29°715 66 48 Ww Cloudy
304 |Noon....| 29°715 76 37 WobySs 5°635 |Fine a its
Even....] 29-710 | 70 AQ W byS Cloudy 60
Morn....] 29-687 | 67 | 50 | WbyN Cloudy 3
31) |Noon....| 29°636 | A8 8 —- |Showery| 74
Even....) — = — = —
Rain, by the pluviameter, between noon on the Ist of July
and noon on the Ist of August, 0°67 inches. The quantity that
fell on the roof of my observatory, during the same period,
0-633 inches. Evaporation, between noon the Ist of July and
noon the Ist of August, 7°015 inches.
1818.) Mr. Howard’s Meteorological Table. 238
ArrTiIcLeE XVII.
METEOROLOGICAL TABLE.
—
BARoMETER,. THERMOMETER, Hygr. at
1818. Wind. | Max.| Min. | Med. |Max. py Med. | 9 a, m. |Rain.
7th Mon.
July 25|\S W1{29°85/29'80/29'825| 77 | 54 | 65:5 e@
261 S 29'85/29°80/29°825| 84 | 62 | 73:0 A5 9
27| N_ |30°22/29:80/30'010| 79 | 51 | 65:0 52
281S W1|30-27|30:22\30'245| 72 | 47 | 59:5 37
29/8 W1|30'27|30:16|30°215) 81 } 56 | 68°5 40
30|S W/30°16|30°10|30:130) 82 | 59 | 70°5 40
31} W_ |30°10)29°97|30:035| 80 | 58 | 69:0 46 12
3th Mon.
Aug. 1 30°18/30°03|30°105| 70 | 50 | 60:0 52
2| S |30°18/30°10/30°140| 70 | 43 | 56:5 50 >
3| S_ |30'10/30°07/30:085| 79 | 47 | 63-0 4g
AIS _E}30°10|30:05|30:075| 87 | 50 | 68:5
5| E |30:03/30:00/30-015| 93 | 57 | 75:0
6} N_ |30°09|30'03/30:060] 88 | 59 | 73°5 40° | —
7|N W/|30°10|30°07|30°085| 76 | 52 | 64:0
8IN W430°10)/29°95|30:025| 78 | 53 | 65:5
9 29°95|29°87|29'910| 82 | 56 | 690 52 ‘e)
10|N E/30°20/29'95|30°075} 72 | 43 | 57°5
1i/N E/30:20)30°10|30°150} 70 | 50 | 60:0 A7
12\N_ E/30°13|30°07|30-100| 72 | 46 | 59-0 50
13/N E/30°13|30°10/30-115| 76 | 45 | 60°5 AT
14\N E/30°10/30'08]30:090] 71 | 53 | 62:0
15|N Ej\30°11|3008/30'095] 68 | 53 | 60°5
16} N_ |3008|30-00!30:040| 76 | 46 | 61°0 C
17| N_ |30°00/29-90|29:950| 76 | 45 | 60°5 omnes
18IN W({29'94)29°88/29:910] 77 | 50 | 63°5
19} N_ |30:04|29'94)29-990| 66 | 46 | 56:0 ere
20} N_ |30:04|30°03/30'035] 66 | 50 | 58:0
21|IN W(30:06|30'00/30-030] 71 | 44°] 57°5
22IN W/|30°20)30:06/30'130] 66 | 43 | 545 39
30*27129'80130'051| 93 | 43 | 63°32 45 10°14
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 result is included in the next following observation,
240 = Mr. Howard’s Meteorological Journal. [Sert. 1818.
REMARKS,
Eighth Month—4. With the exception of a gentle rain in the evening of seventh
month, 31, the steady, fine weather has continued. Much Cirrocumulus of late.
This Gay, in trayeiling, | observed the clouds, both at sun-rise and sun-set, beau-
tifully coloured with a double gradation of tints, in which the respective effects of
the direct and refracted rays were very distinctly marked. 6, Wind in the morn-
ing, SE, brisk, with Cirrostratus and Cirrocumulus; the latter formed in ove instance
oui of Cirrus with unusual rapidity : the wind veered gradually from SE by SW
to NL: at nine, p.m. a strong breeze blowing, withan appearance ofrainto NW,
it began to lighten: at first, a very faint blue flash ; then others, gradually increas-
ing in intensity at intervals of about a minute, filling the air, without being refer-
rible to any point of the compass, followed generally by a sudden puff of wind,
and without thunder. In 20 minutes, however, thunder began to be heard in the
W and NW, and astorm passed in view to the NE, the flasiies broad and vivid on
the whole North horizon, and crossed by delicate striw of a different colour. We
had only a few drops, and it was overintwohours. 7, The sun-set was morerichly
coloured with yellow (passing at length through orange to lake and purple) than I
remember ever to have seen itin this tint before. It literally glowed like a bright
flame on the lower surface of some dense Cirri, passing to Cirrocumulus; which
modification was well marked afterwards. 9, A fine coloured sun-set again, but
in deep orange passing to red, and succeeded by Cirrostratus. 10. Cloudy, with
a brisk wind most of the day: Cirrostratus and dew. 11—13. Fine breeze,
varying to N and E: much dew; twilight, orange; and the moon pale.
14—22. Pretty strong breezes prevailed during this interval; the sky presented
usually the Cumulus passivg to Cumulostratus; but at intervals this modification
took its character from Cir;ocumulus, which entered into its composition from
above. There was scarcely any Cirrus or obscurity above the clouds, but rather
a cold, transparent blue: two or three times the density of the clouds promised
showérs, but it aiways ended in a very slight sprinkling. Coloured skies at sun~
set were frequent; as also the appearance of diverging bars of light and shade,
which I ascertained in several instances to be due to the immense quantity of dust
constantly floating in the air. 22, This morning, being gray with Cirrocumulus
and very cool, seemed like the commencement of autumn; and the warmth of a
fire was acceptable in a north room in the evening,
RESULTS.
Winds Southerly in the fore part; Northerly, with depression of temperature, is
the latter part of the period.
_. Barometer ; Greatest MEIEEES, clone oaipsie cote cere eo OU ed EES
MeHsp sae 6 Slcleitiels! w eletahawietc steht aad NeoroU
Mean of the period. ...........-.- 30051
Thermometer; Greatest height ............2+-++--- 93° .
Weenst. "70. Sc ee 2. slscedebinw coceves -- 43
Mean of the period,..........++-., 63°32
Mean of the Hygrometer.......22. seeeeseeee Aree so 20
Evaporation, nearly. ......0.sccccewececscsseeeees A inches.
ALAA Nisin « ajaisinis'<'siseteeia a nabbnjeictn cia sine siandinieweialalia o's (tuum D Cele
A period unequalled in dryness since the beginning of 1810; when, witha frosty
air, under.a similar course of winds, and the barometer averaging 30-07 in. there—
fell in 30 days only 0:12 in. of rain.
Torrennam, Eighth Month, 26, 1818. L. HOWARD.
ANNALS
OF
PHILOSOPHY.
OCTOBER, 1818.
ARTICLE I.
Biographical Account of M. Senebier.*
THE little republic of Geneva, which has afforded us so many
topics for scientific biography, was the native place of the sub-
ject of this memoir. J. Senebier was born in this city in May,
1742; we have few particulars related respecting his parents ;
but it appears that they were persons of worth and respectability,
and in that middle rank of life which, if not the most favourable
for the development of extraordinary genius, seems to be the
best adapted for the cultivation of the amiable qualities of the
heart. He entered at an early period upon his studies in the
college of Geneva, and was proceeding in them with success,
when his father, who is described as a prudent man of business,
obliged him to abandon his literary pursuits, and to enter upon
a commercial occupation, from which he had himself derived
considerable emolument, and which he wished to transfer to his
son. The wishes of the elder Senebier were given in so decided
a manner, that the young man obeyed without a struggle, he
entered into his father’s office, and appears for a time to have
completely devoted himself to his altered plan of life. A year’s
initiation in his new employment does not, however, appear to
have effected any radical change in his views or wishes ; he still
sighed in secret for a college life, regretted the time which he
had been absent from his studies, and watched, with painful
emotions, the progress which his late associates were making
* The facts in this memoir are extracted from an elogé on M, Senebier by
M. Maunoir, which was read before the Society of Arts in Geneva,
Vou. XII. N° Iv. Q
242 Biuographical Account of fOcr.
in their literary pursuits, in which he was no longer permitted to
accompany them. In this state of mind he wrote a letter to his
father, urgent, but respectful, in which he strongly painted
bis eager desire to resume his former occupations, when the
father, with a degree of forbearance and discretion which is
not very usual under such circumstances, allowed himself to be
ersuaded, and suffered his son to pursue the bent of his genius.
The result was that young Senebier entered upon his college
exercises with unusual ardour ; and in a few months was able to
rejoin the classes to which he had formerly belonged, notwith-
standing the length of time that he had been absent from them.
At the age of 17 he commenced the study of natural philo-
sophy, which afterwards became his chief oceupation ;, and about
the same period he became connected with Le Sage, who,
although 18 years older than Senebier, formed a strong attach-
ment to him, which he ever afterwards retained. At the same
time he went through a course of physiology under Tronchin,
and became so much attached to the pursuit as to have been
strongly inclined to devote himself entirely to the study of medi-
eine. As, however, there appeared no prospect of his being able
to exercise this profession at Geneva, he soon abandoned the
idea; and after deliberating for some time between law and
divinity, he finally decided in favour of the latter, and regularly,
entered upon his theological studies in his 19th year.
Senebier was ordained into the ministry in 1765, and shortly
afterwards undertook a journey to Paris, with his expectations.
raised to the highest pitch of the scientific and literary gratifica-
tion which he was to enjoy in that city. But, as his eulogist
remarks, when he arrived in that immense capital, ignorant of
the world, without experience and without a guide, the brilliant
pictures of his imagination were quickly effaced. As, perhaps,
must always be the case under similar circumstances, he thought
the literary men less interesting than he had conceived them to
be from the perusal-of their works, complained that they were
not communicative, and, after a very short residence in Paris,
left it with his enthusiasm much diminished.
His first publication was a collection of moral tales, which ap-
pear to have been more remarkable for the pure and amiable spirit
which they manifested than for their literary merits. He soon,
however, entered upon the career in which he afterwards became
eminent ; and in consequence of the advice of Bonnet, to whom
he was strongly attached, undertook, in 1768, to answer a prize
question, proposed by the Haarlem Society, on the art of making
observations. This essay was afterwards extended by him inta
a work occupying three volumes, and was published, after an
interval of 30 vears, in its new form, under the title of “ An
Essay on the Art of making Observations and Experiments.”
_ In 1769, in his 27th year, Senebier married, and had the good
fortune to unite himself with an amiable and. excellent woman,
-
1818.) M. Senebier. ; 243
of a disposition and turn of mind very congenial to his own.
Nearly at the same time he was appointed pastor in the parish of
Chaney, about nine miles from Geneva, which is described “as
a delicious rural retreat, where every thing was in harmony with
the state of his heart.” In this situation he spent four of the
most pleasant and useful years of his life, until in 1773 he quit-
ted his rustic abode, and succeeded M. Lullin as the public
librarian of Geneva. Soon after his appointment he undertook
the task, in conjunction with M. Diodati, of forming a catalogue
of the library, arranged according 'to the order of the subjects,
a task which was completed in three years. About the same
period he entered upon the study of chemistry, as a pupil of
Prof. Tingry, and soon began to exercise his pen in discussing
the merits of the doctrine of phlogiston, which was then becom-
ing the great topic of controversy. It was also at this time that
he undertook, at the request of his friend Bonnet, the transla-
tion of Spallanzani’s ‘‘Opuscules de Physique végétale et
animale.”
In the year 1779 M. Senebier published his first memoirs on
the influence of light, a subject in which he afterwards laboured
with much attention, and is the topic on which he may be
considered as having made the most important additions to our
knowledge. His experimental career was stopped for some
time bya severe illness, occasioned, as we are informed, by the
grief which he experienced in consequence of the death of his
father ; but he embraced the first moments of his convalescence
to resume his labours, when he particularly directed his attention
to the green matter which is often formed in water exposed to
the action of light. This had been conceived by some natural-
ists to be of animal origin; but Senebier clearly proved its
vegetable nature, and determined it to be a conferva, affording
a shelter or nidus for numerous insects, but in no way partaking
of their properties. He resumed his researches into the action
of light upon vegetables in the year 1782, and directly opposed
the opinion that had been advanced by Ingenhousz, who con-
ceived the action of leaves upon the air during the night to be
deleterious. Probably in this instance neither of the opinions
that were maintained are correct; but in the course of the
discussion to which the controversy gave rise, Senebier made a
series of important observations, which tended considerably to
enlarge our knowledge on the subject of vegetation and the
chemical change which this function produces onthe air. There
is so much uncertainty in the results of experiments on living
vegetables, that after all the researches that have been made,
there are comparatively but few points that can be considered
as at proved; but among these we may probably rank
one of Senebier’s discoveries, that when the leaves of plants are
acted upon by the sun’s rays, they absorb carbonic acid, decom-
pose it, retain the carbon, and discharge the oxygen.
Q2
244 Biographical Account of M. Senebier {Ocr.
While Senebier was thus pursuing with so much assiduity his
experiments on vegetable life, he was not inattentive to the pro-
gress of the other departments of chemical science. In 1784
he published his “ Analytical Researches on the Nature of
Inflammable Air;” he devoted a portion of his time to meteoro-
logical observations, successively translated the two works of
Spallanzani on generation and on digestion, and at the same
time he drew up “ The Literary History of Geneva.” In the
year 1787, a periodical work was established under the title of
“ The Journal of Geneva,” to which Senebier is stated to have
been a very liberal contributor; and in the following year he
undertook the more difficult and laborious task of writing the
article Vegetable Physiology for the French Encyclopedia. On
this work he probably thought it necessary to bestow a degree
of minute attention which was not customary with him, so that
it was two years in being completed. Shortly after this period,
Geneva became involved in those political revolutions which
convulsed the whole of Europe; and Senebier, who was little
adapted, either by his disposition or his profession, for taking
an active part in these turbulent transactions, retired into the
country, where he remained, as it appears, in a state of complete
seclusion, for nearly 10 years. Part of this time he employed in
reprinting in an enlarged form his treatise on vegetable physio-
logy, which appeared in 1800, extended to five octavo volumes.
During the same period he translated Spallanzani’s travels, and
his work upon respiration: he contributed to the Journal de
Physique, and other periodical works, a number of memoirs on.
various topics; but, for the most part, connected with vegetable
physiology, and in conjunction with his friend Huber published
an essay on germination.
This appears to have been one of the last of his published
works ; but in the list which is appended to the eloge, we find
that a number were left in MS. and some of them of consider-
able size. His death was occasioned by a rheumatic affection
of the left hand and arm, which terminated in a caries of the
bones: amputation of the limb was had recourse to, but without
success, as the operation was succeeded by a fatal haemorrhage,
which appeared to be connected with an ossification of the
valves of the heart. He died at the age of 70 years, and left
behind him the reputation of a man of great moral worth and
much literary industry. After making all the reasonable deduc-
tions for the feelings of friendship which appear so conspicu-
ously in the composition of his eulogist, we cannot doubt that
Senebier was a person of the most amiable dispositions, and the
most pure and upright intentions. He does not appear to have
possessed much strength of character, although there is no cir-
cumstance recorded which would lead us to suppose that he
manifested any remarkable deficiency in this respect, still less
that he degenerated into, any culpable weakness.
1818.] Mr. Dalton on the Lamp without Flame. 245
The same general remarks will apply to his scientific as to
his literary character. There is a mildness and modesty which
pervade his works, an obvious anxiety to arrive at the truth, a
candour towards his opponents, and an air of good faith and
simplicity, which cannot but produce a very favourable impres-
sion on the readers. On the other hand we must acknow-
ledge that the stile is insufferably tedious and prolix, and that
the information which they contain is so much diluted with
common-place remarks as to make them altogether uninteresting
in the perusal. His experiments are numerous, and were pro-
secuted with assiduity ; but they are seldom of that description
which can be stiled masterly or ingenious, but rather belong to
the class which derive their merit from patient observation and
frequent repetition. Upon the whole, however, the results are
not very decisive, and can scarcely be regarded as affording an
adequate compensation for the quantity of time which was
devoted to them. Besides the works which have been mentioned
in the course of this sketch, Senebier was the author of many
other publications on various topics, as well as of a number of sepa-
rate papers in different scientific journals. We apprehend that
few of them will maintain their credit with posterity; they seem to
be written without much care, and to be destitute of that fire of
genius or brilliancy of language, which can give currency to
hasty productions. In short, Senebier wrote too much to write
well; and we may venture to assert that he would have been
more useful to his contemporaries, and better entitled to the
gratitude of posterity, if his works had been less bulky, but more
eorrect.
ArtTIceE II.
On the Combustion of Alcohol by the Lamp without Flame. By
John Dalton, Esq.
(To Dr. Thomson.)
RESPECTED FRIEND, Manchester, Aug. 3, 1818.
On considering the phenomena of the lamp without flame
continuing the combustion of alcohol by means of the coils of
platina wire, it struck me as desirable to ascertain whether the
products in this are the same as in the ordinary combustion; I was
meclined to think that an imperfect or semi-combustion of the
charcoal might, perhaps, be the result, and that carbonic oxide,
rather than carbonic acid, would be found in a confined atmo-
sphere subject to this operation.
About three months ago | suggested the above to Dr. Henry,
when we immediately burned the lamp under a bell glass; and
extracting a portion of the airjwe were soon convinced by the
ordinary tests that it contained carbonic acid. A few days
246 Col. Beaufoy on the Spiral Oar. [Ocr.
afterwards I repeated the experiment with a view to find whether
any carbonic oxide was mixed with the acid; the lamp was
burned under a bell glass of 120 cubic inches till the redness of
the wire ceased to be visible in the dark, when a phial of the
air was extracted for examination ; as soon as the bell glass was
removed, the wire resumed its original glow again, which
showed that the combustion had not ceased. On examining the
air over mercury in the usual manner, I found it contained 14}
per cent. of oxygen and about four per cent. carbonic acid ; but
{ could discover no more carbonic acid by firing the residue with
the addition of hydrogen and a little oxygen.
Thus it appeared that my conjecture respecting the produc-
tion of carbonic oxide was not supported by experiment ; this
kind of combustion proved to be rather more than less vigorous
than the ordinary one, as the oxygen was reduced rather more
than it would have been by the common combustion carried
to extinction.
In order tu examine this last point more fully, I caused the
lamp to burn with flame under the same bell glass filled with
atmospheric air, till it was extinguished spontaneously. The
residuary gas was found to consist of 161 per cent. oxygen, and
three carbonic acid. Again, the lamp without flame was burned
under the same glass in like circumstances, and kept for 40
minutes, when it was quite extinct; the residuary air being
examined was found to contain only eight per cent. oxygen, and
nearly the same quantity of carbonic acid.
I have frequently found on former occasions that the combus-
tion of oil, wax, tallow, &c. all reduce the oxygen nearly in the
same degree before the combustion is extinguished, namely,
four, five, or six per cent. it being 21 per cent. at the commence-
ment. It appears to me, therefore, a very singular and remark-
able fact, that this species of combustion should be enabled to
reduce the oxygen so much, or to support itself in circumstances
in which the ordinary one entirely fails.
I remain, yours truly,
Joun DaLTon,
Articxe III.
Observations on the Spiral as a Motive Power to impel Ships
through the Water, with Remarks when applied to measure the
Velocity of Water and Wind. By Col. Beaufoy, F.R.S,
(To the Editors of the Annals of Philosophy.)
GENTLEMEN, Bushey Heath, July 22, 1818.
In the Annals of Philosophy for last June, an ingenious plan
is given for impelling vessels through the water with. a spiral oar,
18182] Col. Beaufoy on the Spiral Oar, 247
and which Mr. Dick is of opinion might be usefully employed in
propelling ships of war. A contrivance of this kind I saw,
between 30 and 40 years past, in Switzerland, in the model
of a flat-bottomed vessel, brought by Monsieur Bosset from the
East Indies, but made in China ; this model had underneath its
bottom a spiral, which was turned when wanted with consider-
able rapidity by clock-work, put in motion by a spring similar
to a watch; the vessel being placed in a tub full of water, the
spring wound up, and the helm put over, more or less according
as the tub was large or small, the boat continued running in a
circle until the clock-work went down.
I witnessed an experiment on a much larger scale, made in
Greenland Dock by Mr. Lyttleton, formerly a master in the
Royal Navy. This gentleman had fixed to the stern-post of a
Virginia pilot-boat, a frame containing a large copper spiral,
which, by a winch, turned by two or more men, gave it a rotary
motion; the effect was much less than expected ; for notwith-
standing the boat was completely empty, and considerable
exertions used, the progressive velocity did not exceed the rate
of two knots per hour.
As a perpetual log, the spiral* has been used, and found
very useful in maritime surveying, by measuring a base line on
the water. This method of findmg the distances of one head-
Jand from another, is rendered useless, if the spiral be placed
within a concave cylinder ; for the friction of the water against
the inside impedes its progress, consequently the distance shown
by the perpetual log is less than the true. Being requisite that
the number of revolutions made by the spiral be noted, it 1s most
advantageously done by a line and clock-work, one end being
attached to the log, the other to the clock ; but as the friction
of the clock-work, and the resistance the line meets with by
revolving in the water, impede the rotary motion of the spiral,
an allowance must be made for the error by placing the clock on
board a vessel towed in a stagnant canal, and measuring with a
perambulator, on the tract-path, the distance the vessel has
moved, the difference of the space shown by the perambulator
and the log is the error of the spiral; should the water have a
slow motion, as is generally the case in our canals, the same
distance should be measured both with and against the stream,
and the mean of the two numbers of revolutions taken for finding
the error.
The spiral may also be applied to measuring the velocity of the
wind ; and itis better in this case, as well as the former, to have
two leaves, or a double spiral, each leaf making a half revolu-
tion, than a single worm, which makes a complete turn. Mr.
William Cary, optician in the Strand, made me a machine of this
* Invented by the celebrated Dr. Hooke.
248 Col. Beaufoy on the Spiral Oar. ‘fOcr.
kind. The accompanying drawing, fig. 1, represents the spiral>
which consists of a double worm, a a, 20°8 inches in diameter»
exclusive of the leaves, the cylinder d d round which it twines is
171 inches long; the parts a a are of brass, three inches broad;
the clock-work (not represented in the drawing) consists of a
pinion of 10 teeth fixed to the pivot of the axis d d, which gives
motion to a contrate wheel of 40 teeth fixed to an upright axis
passing in front of the frame; at the bottom of the upright axis
1s a small single thread worm, which turns a wheel of 50 teeth ;
on the axis of this wlieel is fixed a long hand, which points out
200 yards in one revolution ; on the other axis is placed a pinion
of 10, which turns a wheel of 100, and shows, by a second
but smaller hand 2.000 yards, or nearly one nautical mile ; on
the other axis of this wheel is also a pmion of .10 teeth, which
communicates with another wheel of 100 teeth, and by another
index, or third hand, shows 10 miles; on this axis, likewise,
there is a pinion of 10 teeth, which tums another wheel of 100
teeth, and by an index, or fourth hand, points out 100 miles.
Fig. 2, represents a spiral log, the thick part of the machine
is of wood, for the double purpose of floating and fastening the
tin or copper leaves cc. Ifthe spiral be truly made, and not
resisted in revolving, it is evident it will make one revolution or
half a revolution, whilst it moves through a space equal to the
length of its axis, one revolution if the twist make a whole turn,
half'a revolution if the twist go only halfround ; for the resisting
medium may be considered as a concave screw, and the spiral
as a convex one running into the former. To cut a plate of
metal the proper shape, it is necessary to have the dimensions
of the cylinder round which thé metallic plate is to be bent. The
length of a spiral going half round the cylinder is equal to the
square root of the sum of the squares of the cylinder’s length,
and half its circumference ; and the diagonal of the cylinderis the
1818.] Col. Beaufoy on the Spiral Oar. 249
chord of this circle. To calculate the radius sufficiently accurate
for practical purposes, add to three times the length of the arc
the diagonal of the cylinder ; from + of the sum add and subtract
half the diagonal of the cylinder, then multiply the sum and
difference of these numbers together, and the square root of the
heal the versed. sine of the arc. Next divide the square of
alfthe chord by the versed sine, to the quotient add the versed
sine, and half the sum is the radius of that part of the metallic
curve next the cylinder. Besides giving the inner and outer
edge of the metal a circular form, a second operation becomes
necessary, which is hammering the plate to elongate the outer
edge, begmning at the part next the cylinder, and gradually
proceeding to the outer edge. Without this operation the me-
tallic leaf which forms the spiral would not, when fixed, be
perpendicular to the cylinder. This part of the work being so
difficult that few workmen can execute it well, it depends on
science to invent a machine, perhaps by passing the metallic
leaf between conical rollers, which, by pressure, might supersede
the necessity of hammering, and would render this instrument
of more practical utility. {In conclusion it must be remarked,
that it was originally intended that the axis of the wind spiral
should have measured 18 inches, but the difference, half an inch,
was designed to allow for the friction of the machine and the
resistance of the air to the radii. For the purpose of determin-
ing if half an inch was a sufficient allowance for the impediments
the spiral met with when turning,.an upright and revolving shaft
was erected, from which projected an horizontal arm, to the
extremity of which was fixed the frame of the wind spiral, the
upright shaft being turned a given number of revolutions: the
space the extremity of the arm moved, calculated and compared
with the distance shown by the spiral, the difference was as
1000 to 779, that is, the spiral in moving 1000 yards gave the
distancé too small by 221 yards: a table being constructed, the
true velocity may be had by inspection.
Trusting some of your readers will not deem the subject
unworthy their consideration, I remain, Gentlemen,
Your obedient humble servant,
Mark Beavroy.
ARTICLE IV.
Memoir relative to the Annular Eclipse of the Sun, which will
happen on September 7, 1820. By Francis Baily, Esq.
(Concluded from p. 186.)
Havine thos given a general outline of this eclipse, I shall
proceed to state the principal phenomena which have been
250 Mr. Baily on an | [Oct.
observed in former eclipses of this kind,* whereby the reader
may be aware of the principal observations to which it will be
proper for him to attend, and make his preparations accordingly.
Many of these phenomena have given rise to much discussion,
and are far from being accurately determined, or reduced to
general principles. There is also a degree of doubt respecting
the existence of some of them. Those persons, therefore, who
are furnished with convenient instruments, and have a favourable
opportunity, should carefully attend to, and note dcwn, not
merely the phases of the eclipse, but such other appearaaces as
may present themselves. It is only by multiplying observations
of this kind that we can ultimately arrive at the truth: and an
annular eclipse is so rare an occurrence in this part of the globe,
that it is hoped every advantage will be taken of it, to improve
and advance the connected sciences of astronomy and geo-
raphy.
There is one important observation, however, connected with
this eclipse, which it is in the power of almost any competent
_ to make, without the aid of any particular instruments :
allude to the formation and dissolution of the annulus.+ This
may be determined very accurately, if not by the naked eye, at
least with a telescope of very small magnifying power ; { fur-
nished with a coloured glass to keep off the rays of the sun, or
with a glass smoked in the manner hereinafter mentioned.§ The
times of these phases may be determined with sufficient accu-
racy by means of a clock, or watch that beats seconds; and
which should, if possible, be set to mean time on the day of the
eclipse. The neglect of this precaution, however, should not
prevent the observer from noting down the duration of the
annular appearance; which will be the same, whether the
watch is nght or not.|| As the method, therefore, of observing
this phenomenon is so simple and easy, it is hoped that no
dl
: * Those of 1737 and 1748, There are but few observations of the eclipse of
7164,
+ The annulus is considered as completely formed when the whole body of the
moon just appears on the disc of the sun, however unequal in breadth the unco-
vered part of the sun’s disc may be. It is considered as dissulved the moment the
moon again touches the concave circumference of the sun’s disc. The duration of
the annulus will not in any place, as already observed, exceed six minutes, and in
some places will be momentary.
$ A common opera giass might be made use of, if nothing better should present
itself: as no method should remain untried for determining this very important
phase. If the observer be near-sighted, and have not the advantage either of a
telescope or concave glasses, he may view the sun through a small hole made ina
card by meansof a pin.
§ Those who cannot procure either coloured or smoked glass may view the
image of the sun in a bucket of water, ora vessel filled with oil, placed ina situa-
tion where it may not be agitated by the wind. .
| Should the observer be in such a situation as not to have the advantage of
either a clock, or a watch beating seconds, he might easily make a temporary pen-
dulum, of any convenient length, and notice the number of vibrations which it
makes during the existence of the annulus, In such case, the length and substance
of the pendulum should be specified. “Das
1818] Annular Eclipse of the Sun, 251
person, to whom the opportunity may occur, will omit to note
down the particulars ; or fail to communicate the same to some
person conversant with the subject of astronomy. It will be of
equal importance to know that the existence of the annulus is
only momentary: or even that it is nearly, but not completely
formed.*
Athough the possession of proper instruments must give a
superior degree of credit to the observations of any person; yet
{ would not discourage those who have not this advantage from
communicating any circumstances that may occur. For it has
been justly observed by M. De L’Isle, that although no great
dependance can be placed on those observations which are not
made with a telescope, &c. yet that such observations as are
made with the naked eye ought not to be entirely neglected;
since it affords us an opportunity of judging of the accuracy of
those observations which were made before telescopes, &c. were
invented.
Those persons, however, who have the proper instruments,
and every conveniency for observing, will of course note down
the usual circumstances in such case: viz.
1. The time of the commencement of the eclipse.t
2. The time of the formation of the annulus.
3. The time of the dissolution of the annulus.
4. The time of the end of the eclipse.
If there should be any spots on the sun, it will be proper
(previous to the commencement of the eclipse) to make a diagram
of the sun’s disc ; and to note down the times when the body of
the moon comes in contact with the spots, and likewise the times
when they again become visible. All these may be determined
* To those who are not much conversant with practical astronomy, it may, per-
haps, be proper to remark, that the more numerous these observations may be
(that is, the greater the number of places where they are made), the more import-
ant will be the consequences to be derived from them, Consequently every obser-
vation will be material. Those persons who may observe the eclipse in the
country should state the distance and position of such place from the nearest
principal town,
+ It is rather difficult to determine the exact time of the commencement of any
solar or lunar eclipse; since the impression on the disc does not become visible till
some seconds after the eclipse has begun. The field of the telescope should take in at
Jeast one half of the circumference of the sun’s disc (taking that portion of it which
may leave the expected point of contact in the centre), as the eye can much better
judge of any impression made upon a large, than a small portion of acircle. In
some cases, however, a very powerful telescope (which takes in only asmall portion
of the sun’s disc) may be attended with advantage, as in the case of the solareclipse
on Sept. 5, 1793, where Sir Wm, Herschel observed that the first impression on the
sun’s dise was made by the projection of two high mountains of the moon, having
the appearance of horns; which were distinctly visible on the sun’s disc before the
body of the moon appeared.—Phil. Trans, 1794, page 39.
¢ In order to determine, with greater accuracy, the formation and dissolution
of theannulus, the observer should take into his telescope that part only of the disc
of the sun which is necessary for the purpose. By adopting this method Mr,
Maclaurin, in 1737, was enabled to observe the appearance alluded to in page 254
and which preceded the perfect formation of the annulus about 20 seconds; thereby
enabling him to look out for and note down the exact time with greater precision,
252 Mr. Baily on an [Ocr.
with sufficient accuracy by the assistance of a telescope magni-
ing 30 or 40 times ; together with a well regulated clock, or
watch, that beats seconds; and which, if possible, should, as
before observed, be set to mean time on the day of the eclipse.*
I must again repeat, however, that the neglect of this precaution
should not deter the observer from noting down the duration of
the several phases above-mentioned, and particularly the times
at which the annulus is formed and dissolved: which may be
afterwards compared with more exact observations, and lead to a
correction of the true times.+
It is presumed that the observer will also, from time to time,
during the progress of the eclipse, observe and note down the
distance and inclination of the cusps in the usual manner.{ It
may likewise be proper to remark that it will be of considerable
importance to ascertain, at the time of the middle of the eclipse,
the magnitude of the annulus on the north and on the south side
of the moon, in order to determine how far distant, at that time,
the centre of the moon is from the centre ofthe sun.§_ If at the
same moment the observer can determine the diameter of the sun
and moon, it will add considerably to the importance of the
observation ; and tend to determine a much disputed point in
practical astronomy. || These observations, however, should be
made with a good telescope furnished with an accurate micro-
meter: and, in making a report thereof, the observer should
describe the kind of telescope made use of, as well as the method
employed in determining the magnitude of the annulus, &c. For
the sake of greater accuracy, he should also make a diagram of
the appearance of the sun and moon, at the time of the middle of
the eclipse; placing a mark against that part of the sun’s dise
which appears the most vertical to him. The point on the cir-
* Inthe evening of the same day on which this eclipse takes place there will be
- an eclipse of the first satellite of Jupiter: the immersion will take place at Green-
wich at 84 34’ 34” mean time. Those persons, therefore, who are furnished with
sufficiently powerful telescopes, may (if the weather prove favourable) have an
opportunity of ascertaining the correctness of their clocks or watches.
t M. De L’Isle states, that if we observe the situation of the cusps, er only their
distance, at the time of the middle of the eclipse (when the eclipse is not annular,
but nearly so), it will serve to determine the apparent route of the penumbra and
its limits, as exactly as if we had observed the duration of the annular eclipse.
} There are two modes of observingihe phases of an eclipse of the sun: the oue,
by looking directly at the sun, with a telescope furnished witha micrometer; the
other, by receiving the image of the sun, through a telescope, on ascreen, inadark
chamber, or camera obscura. Each has itsadvantages, and may be practised accord-
ing to circumstances, See Lalande’s Astronomie, vol. ii. p. 659. M. De L’Isle
indeed says, that ‘‘ we may determine, with sufficient exactness, the situation of
the cusps, without making use either of the dark chamber or the micrometer, by
observing the moment of the passage of the cusps and of the limbs of the sun, by
means of simple wires placed in the focus of the telescope, in any situation what-
ever; and leaving the telescope in a fixed position, during the time that the sun
employs to traverse the field of it.”
§ M. De L’Isle doubts whether this part of the observation can be made with
sufficient accuracy in a dark chamber; on account of the indistinctness of the:
image of the moon.
l] See next page.
1818.] Annular Eclipse of the Sun. 253
cumference of the sun’s disc (relative to its vertical or horizontal
diameter) where the moon leaves it in order to form the annulus,
and again where it touches it at the time of the dissolution of
the annulus, should also, if possible, be distinctly noted. M. Le
Monnier considers this of considerable importance.*
It was observed, in the annular eclipse of 1737, that the annu-
lus was formed and dissolved very suddenly. For when the
whole body of the moon had entered on the disc of the sun, the
last portion that entered appeared to adhere to the concave cir-
cumference of the sun’s disc for seme seconds ; and the moon
appeared elongated on that side, till the sun’s light suddenly
broke round it, when the moon reassumed its regular curvature.
In asimilar manner, when the disc of the moon approached the
concave line of the sun’s disc on the other side, they seemed to
run together like two contiguous drops of water on a table when
they touch each other.
It was also observed, in the eclipse of 1737, “ that as the
annulus was forming, the light appeared to break in several irre-
gular spots near the point of contact: and that the limb of the
moon seemed to be indented there.” These irregular parts
seemed likewise to have a kind of motion ; although there was no
undulation at the same time in the circumference of the sun.
Such appearances of a tremulous motion, in certain periods of
solar eclipses, are mentioned by Hevelius and others. It was
noticed also in the eclipse of 1748.+ :
In both these eclipses, as well as in that of 1764, it was
observed, that when the annulus was formed, the moon appeared
much smaller on the sun than it really ought to be ; and indeed
much smaller than the calculations seemed to warrant. But
whether this phenomenon arises from an apparent enlargement
of the sun’s disc, or trom an apparent diminution of the moon’s
dise, or from both, does not seem clearly decided. M. Du
Séjour has discussed this subject, with his usual ability, in his
Traité analytique des Mouvemens apparens des corps célestes,
vol.i. page 405, &c.; but he has not come to any precise deter-
mination thereon. ‘The observations have not been made with
sufficient accuracy, nor are they sufficiently numerous to enable
us to determine so nice an element in the calculation of eclipses.
* Tn hispaper Sur [ Utilité des Eclipses de Soleil ‘wherein he has drawn many im-
portant consequences from the eclipse of 1748) he remarks, respecting the method
of determining the limits of the umbra, that * la plapart des observateurs, en
pareil cas, suivent les routes ordinaires, et n’out jamais fait assez d’atteniion aa
point de lacirconférence du limbe du soleil od se forment les roptures de |’anneau:
de-ormais ces points de la circonférence du disque du soleil seront les plus import-
aus, et nous foarniront les limites que nous youdrons bien assiguer.”—Mem. de
VAcad. des Sciences for 1765, p. 463.
+ The Rev. Mr. Irwin, who noticed the eclipse of 1748 at Elgin, says that “the
formation and breaking of the aonulus were sensibly to be observed, and passed in
@ moment; affording a very pleasing sight by the irregular tremulous spots of the
suo,”’—Phil. Trans, vol, aly. p. 595,
254 Mr. Baily on an [Ocr.
It is hoped, therefore, that the attention of astronomers will be
more drawn towards this subject in the ensuing eclipse.*
In the eclipse of 1737, Maclaurin observes that about 20
seconds “ before the annulus was complete, a remarkable point
or speck of pale light appeared near the middle of the part of the
moon’s circumference that was not-yet come upon the disc of
the sun; and a gleam of light, more faint than that point,
seemed to extend from it to each horn.”
In the eclipse of 1748, it was noticed that there was “ about
the middle of the eclipse, a remarkably large spot of light, of an
irregular figure, and of a considerable brightness, about seven or
eight minutes within the limb of the moon.” Mr. Short states
that. this eclipse was not quite annular at Aberdour Castle : “the
cusps seemed to want about + of the moon’s circumference to be
joimed, yet a brown light was plainly observed both by ray Lord
Morton and myself to proceed or stretch along the circumfe-
rence of the moon, from each of the cusps, about + of the whole
distance of the cusps from each cusp ; and there remained about
x of the whole distance of the cusps not enlightened by this
brown light.”—“ I observed at the extremity of this brown light,
which came from the western cusp, a larger quantity of light
than in any other place, which at first surprised me ; but after-
wards I imagined it must have proceeded from some cavity or
valley made by two adjoining mountains on the edge or limb of
the moon. I had often formerly observed mountains on the
circumference of the moon, more or less every where round it,
but never saw them so plain as during the time of this eclipse.
The mountainous inequalities on the southern limb of the moon
were particularly remarkable; in some parts mountains and
valleys alternately ; others extended a considerable way along
the circumference and ended almost perpendicularly like a pre-
cipice. My Lord Morton was able to see them very easily
through his small reflector.”
The King of France, who (as already mentioned) went pur-
posely to Compiegne to observe this eclipse, discovered towards
the middle of the eclipse (which was not more than 93 digits)
“ sur la surface de la lune, comprise entre les cornes du soleil,
des rayons de lumicére rouges, et un filet de lumiére qui sembloit
masquer le disque de la lune, et qui s’étendoit 4 une distance
des cornes.+ ”
M. De L’Isle, in his publication above alluded to, seems to
think that a quick eye, guarded with a sufficiently dark glass,
* See Lalande’s Astronomie, vol. ii. p. 445; Delambre’s Astronomie, vol. ii*
p. 423; and also M. Le Monnier’s memoir Sur les Eclipses totales du Soleil, in the
Mem. de I’Acad, des Sciences for 1781, p. 243, In this memoir there is a map of
the path of the moon’s umbra in the total eclipse of May 22, 1724, and which ap-
pears to have proceeded over great part of England: nevertheless 1 cannot find
any observation ef it in this country.
+ Mem, de l’Acad, Roy. des Sciences, 1748, p. 56.
5
1818.) Annular Eclipse of the Sun. 255
might, in solar eclipses, discover the body or limb of the moon
seven or eight minutes before it touched the sun, and also for the
same time after it had left it and was entirely off the sun. He
-remarks that the observer should defend himself as much as
possible from the direct light of the sun, and also from the light
of the external air. No person, however, has hitherto noticed
such an appearance; although many observers attended particu-
larly to it, in the eclipse of 1748, in consequence of M. De
L’Isle’s remarks. Should the moon in such case ever be visible,
it would enable us to determine with greater accuracy the com-
mencement of any solar eclipse.*
During the progress of the eclipse it would be desirable to
ascertain the degree of cold and obscurity caused by the dimi-
nution of the sun’s rays ; for which purpose preparations should
be made before-hand, in order that no time be lost during the
SS of the eclipse. The variations in the thermometer and
‘barometer may be easily noted down without interrupting the
astronomical observations. The rapid change in the tempera-
ture of the air may cause a hurricane of wind (together with rain
or snow), as was observed about the middle of the eclipse by
Mr. Maclaurin in 1737 ; and by Le Monnier in 1748. Mr. Short
says, that (in the eclipse of 1748) “ we did not at all perceive
or feel any greater degree of cold, during the eclipse, than we
felt before it began.” But M. Cassini De Thury, who went
with the King of France to Compiegne to observe this eclipse,
and where it was only 91 digits, says, they experienced a con-
siderable degree of cold at the time of the middle of the eclipse;
the thermometer, however, fell only 21°: and the Abbé Nollet
found that his burning-glass was then as powerful as before the
eclipse began. M. De L’Isle, likewise, who observed this
eclipse at the Luxembourg, remarks, that the thermometer did
not indicate any increase of cold caused by the eclipse, although
he and many other persons experienced it soon after the middle
of the eclipse.+
In the eclipse of 1737, Maclaurin observed that a burning-
= which kindled tinder and burned cloth towards the end of
e eclipse, had no effect during the existence of the annulus,
nor for some time before and after it. He likewise remarked,
that “ during the appearance of the annulus, the direet light of
* It must be evident to the practical astronomer, that if the moon were really
visible in such cases, she would also be frequently visible at the conjunctions,
when no eclipse took place. M. De L’Isle’s suggestion arose from a remark made
by M, Cassini on a luminous ring which was seen to surround Mercury in its pas-
sage across the sun’s disc in the year 1736, and which continued for six or seven
seconds after Mercury was entirely off the sun’s disc. See Mem, de }’Acad, des
Sciences for 1736, p. 373,
+ In the total ectipse of 1724 the thermometer had fallen only two degrees at
the time of the middle of the eclipse. This is the more remarkable as the eclipse
took place late in the afternoon of May 22, at which time we might presume that
the atmosphere would be gradually becoming more cool. The total darkness took
place at 6" 48! p, m,
256 Mr. Baily on an [Ocr.
the sun was still very considerable; and that although some
places that were shaded from his light appeared gloomy, yet that
the day-light was not greatly obscured.” He adds, that many
persons, about the middle of the annular appearance, although
not short-sighted, were unable to discover the moon upon the
sun when they looked without a smoked or coloured glass.*
Nevertheless Venus and some other stars were visible at the
same time ; and Venus continued visible even after the annulus
was dissolved. Venus was also seen in the eclipse of 1748, but
it does not appear that any other star was then visible.
If the diminution of hght should be considerable (which there
is not much reason however to suspect,}+) Mercury, Venus, and
Mars, together with some of the principal fixed stars, may be
visible to the naked eye. Mercury, if visible, will be seen about
18° to westward of the sun, nearly in conjunction with Regulus:
Venus will be about 41° to westward of the sun:} and Mars
about 35° to eastward of the sun, not far from Spica Virgints,
The observer should also look out for any comet which may be
visible during this eclipse; and be prepared to measure its dis-
tance from the sun or a principal fixed star.
As many persons may be so situated as not to be able to pro-
cure any dark-coloured glass, for the purpose of viewing the
sun, I shall conclude this memoir by inserting Dr. Maskelyne’s
method of smoking glasses, which he published in the Nautical
Almanac for 1769, in his Instructions relative to the Observation
of the Transit of the Planet Venus over the Sun’s Disc in that
ear.
rc Dark glasses should be used to defend the eye from the
intensity of the sun’s light. Transparent glasses, smoked over
the flame of a candle or lamp, will give a more distinct and
agreeable vision of the disc of the sun than any tinged or
coloured glasses will do.. Provide two pieces of glass of conve-
nient length, not too thick (the common crown glass, used for
windows, will do as well as any), wipe them clean and dry.
* M. Le Monnier mentions the same thing of himselfin the eclipse of 1748.
+ In the annular eclipse of 1764 an ignorant country clergyman alarmed the
people of France by announcing that there would be total darkness during the
existence of the annulus; and the Royal Academy of Sciences at Paris thought
proper to give this report a formal contradiction. Itis well known, however, that
the smallest ray of light from the sun would prevent such a phenomenon; as Ihave
shown more at length in niy paper ‘* On the Solar Eclipse which is said to have
been predicted by Thales,” inserted in the Phil. Trans, fur 1811, part ii, p. 220.—
I shall here take the opportunity of correctinga typographical error in that paper;
where, in page 240, line 22, ‘* three degrees ” should be ‘* three minutes.’ Since the
publication of that paper, I find that the Bureau des Lengitudes in France have
printed a Supplement to M. Burgh’s Lunar Tables, wherein the mean epoch and
mean motion of the Sapplement of the Node are considerably altered: so as to
bring the latitude of the moon within the limits which I there suggested.
t In the total eclipse of 1715, Venus was seen when only nine digits were
eclipsed: but she was not seen at Compiegne in the eclipse of 1748, although the
digits eclipsed were 93 ;~in the eclipse of 1724, however, she was distinctly visible
when only six digits were eclipsed. This is not remarkable, as she is, in some
situations, visible even at mid-day,
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1818.] Annular Eclipse of the Sun. 257
Warm them a little by the fire (if the weather be cold) to prevent
their cracking when applied to the flame of the candle: then
draw one of them gently, according to its whole length, through
the flame; and part of the smoke will adhere to the glass.
Repeat the same operation, only leaving a little part at one end
now untouched ; repeat the operation, leaving a further part at
the same end untouched, and so each time leave a further part of
the same end untouched, till at last you have tinged the glass
with several dyes, increasing gradually in blackness from one
end to the other. Smoke the other glass in like manner, and
apply the two glasses, one against the other, only separated by
a rectangular border, cut of brass or card paper, the smoked
faces bemg opposed to each other, and the deepest tinges of
both placed together at the same end. Tie the glasses firmly:
together with waxen thread, and they are ready for use. The
tinge at one end should be the slightest possible, and at the
other end so dark that you cannot see the candle throughit. By
this contrivance, applied between your eye and the sun, you will
have the advantage not only of seeing the sun’s light white,
according to its natural colour, and his image more distinct than
through common dark glasses, but also of being able to inter-
cept more or less of his light as you please, and as the clearness
or thickness of the air requires it, by bringing a-darker or lighter
part of this combined dark glass before your eye ; which will be
a great convenience at all times, but particularly when the bright-
ness of the sun is liable to sudden changes from flying clouds.’
I shall merely add, that it is to be hoped the Sovereigns of
the different provinces and states, mentioned in this Memoir
(page 184), will encourage persons from the neighbouring coun-
tries to enter and observe this eclipse: and that the love of
science will induce them to prevent such persons from being
subject to any tarif, or vexatious delay at the Custom-house, on
account of any astronomical or philosophical instruments which
they may take with them for the purposes of observation.
ARTICLE V.
Researches on various Fatty Bodies, and particularly on their
Combinations with Alkalies. By M. Chevreul.
; (Concluded from p. 199.)
M. Chevreul’s Sixth Memoir *
_ Tue subject of this memoir is the different kinds of fat ; par-
tieularly that of man, of the sheep, the ox, the jaguar, and the
goose. Before he enters upon the proper topic of this memoir,
* Abstracted from Ann, de Chim, et de Phys. ii, 339, (Aug. 1816.)
Vou. XII. N° IV, R
258 M. Chevreul on Fatty Bodies, and _ [Oer.
the author takes a review of what he has done in the five preced-
ing papers. He observes that in the first he described a body,
which unites the characteristic properties of acids to all the
generic properties of the fats and oils. This body, which he has
named margarine, has served as the type of a new kind of
ternary acid, and bears the same relation to the oxygenated
vegetable acids as the hydrogenated do to the oxygenated acids
in the morganic kingdom.
The object of the second memoir was to analyze the products
of the saponification of hog’s-lard as effected by potash. After
having deprived the soap of its margarine, a fatty body was
obtained from it which was denominated fluid fat. This body,
hke margarine, unites to potash in two proportions, but it differs
from it in fluidity, and in the solubility in cold water of its
saturated combination with alkali. The examination of the fluid
from which the soap is separated has shown that in saponifica-
tion a sweet principle is produced, similar to that which Scheele
observed in water, in which olive oil has been treated with prot-
oxide of lead. These researches then have established that
soap, which had been regarded as a compound of a fatty matter
and an alkali, is really a double compound of alkali and of two
fatty acid bodies.
he composition of ‘soap being thus determined, in the third
memoir the following facts were established: 1. That the essen-
tial products of saponification are margarine, the fluid fat, and
the sweet principle ; but that the odorous and colouring prin-
ciples found in many soaps appear to be accidental: 2, That
oxygen gas is not necessary for saponification : 3. That saponi-
fied fat is formed of margarine and of the fluid fat, and conse-
quently possesses acidity: natural fat is formed of two new
proximate principles, one of which is analogous to tallow, and
the other to the liquid oil of vegetables; but both of these
principles differ from those of saponified fat; for instead of
being acid, they rather appear to possess an alkaline nature:
4. The experiments have also shown that the saponification of
hog’s-lard depends upon two causes that are inseparable ; first,
upon the elementary composition of this fat, which is such, that
it may be represented either by the two immediate. principles
which constitute it, or by the sweet principle, margarine, and
the fluid fat ; secondly, upon the sweet principle, and still more
the margarine and the fluid fat, having an affinity forpotash much
superior to the immediate principles, of fat for the same base,
from which it results, that m saponification the potash deter-
mines the fat to be converted into the sweet principle and the
two acid substances. This total conversion of an organic matter
into many substances, which are themselves compounds, and
very different from the matter itself, may explain many pheno-
mena in physiology, where bodies assume forms totally different
from those which they previously possessed.
6
i
;
>
)
|
1818.] their Combinations with Alkalies. 259
In the fourth memoir, saponification was examined under two
relations ; 1. Under that of the bases which form it; 2. Under
that of the quantity of alkali necessary to saponify a certain
quantity of fat. The first inquiry, by showing that barytes,
strontian, lime, oxide of zinc, and protoxide of lead, cause fat to °
undergo the same change that it does with potash and soda, has
enabled us to generalize saponification, by proving that this oper-
ation depends upon analkaline force which overcomes the obstacle
which the cohesion of some bases and the insolubility of others
seem to oppose to the change of fat into the sweet principle and
the oily acids. The second inquiry, by showing that we can
effect the saponification of a given weight of fat, merely by
employing the quantity of alkali which is exactly necessary to
neutralize the margarine and the fluid fat, into which this weight
of fat can be converted, has formed a determinate basis for the
art of the soap-maker. In this memoir, likewise, the capacity
of the saturation of margarine has been exactly determined, and
all the analyses of the soaps of this substance have shown that
100 parts of it saturate a quantity of base containing three parts
of oxygen. There appears then to be a perfect analogy between
margarine and the acids, so as to confirm the opinion of its
nature which had been advanced in the preceding memoirs.
The crystallized matter of the human biliary calculus, sperma-
ceti, and the adipocire of carcasses, had been confounded
together under the same species of fatty matter ; and the object
of the fifth memoir was to show that this opmion is erroneous.
The biliary calculus and spermaceti possess the characters of
pure proximate principles, whilst adipocire, which is formed of
margarine, of fluid fat, and of an orange coloured principle,
sven all the properties of a saponified fat. On the other
and, biliary calculus differs essentially from spermaceti, as the
latter is perfectly saponified under circumstances in which the first
absolutely resists the action of alkalies. The soap of spermaceti
contains two oily acids, one of which only has been examined ;
it is in its general characters analogous to margarine and the
fluid fat, but is distinguished from them by possessing only
about half as much capacity for saturation.
The knowledge of the immediate principles. which compose
the different kinds of fats and oils accounts for the different
degrees of fluidity of their compounds, but it does not explain
the differences in colour and odour which many of them present.
The discovery of the cause of these differences gives rise to a
new order of facts, which will form the subjects of the succeeding
memoirs. In the present memoir, the sixth, M. Chevreul pro-
poses to examine the fat of man, of the sheep, the jaguar, and
the goose ; and to determine how far the proximate principles of
these fats, and the oily acids which they are capable of produc-
ing, resemble those of hog’s-lard.
e author remarks that he has hitherto made use of peri-
R 2
~
260 M. Chevreul on Fatty Bodics, and [Ocr.
phrases when speaking of the different bodies that he has been
describing, as supposing that their nature was not sufficiently
determined. He now, however, conceives that he may apply
specific names to them, which will both be more commodious,
and, at the same time, by being made appropriate, will point out
the relation which these bodies bear to each other. The follow-
ing is the nomenclature which will be hereafter adopted. The
crystalline matter of human biliary calculi is named cholesterine,
from the Greek words xy bile, and sepeos solid ; spermaceti is
named cetine, from xytoc, a whale; the fatty substance and the
oily substance, described in the third memoir, are named respect-
ively stearine and elaine, from the words szag fat, and edsuoy oil ;
margarine and the fluid fat are named margaric acid and oleic
acid, while the term cetic acid is applied to what was named
saponified spermaceti. The margarates, oleates, and cetates, will
be the generic names of the soaps or combinations which these
acids are capable of forming by their union with salitiable bases.
The author begins his examination of the different kinds of
fat by giving an account of the different properties which they
exhibit in their entire undecomposed state.
Two portions of human fat were examined, one taken from the
kidney the other from the thigh; after some time they both
of them manifested a tendency to. separate into two distinct sub-
stances, one ofa solid and the other ofa fluid consistence ; the
two portions differed in their fluidity and their melting point.
These variations depend upon the different proportions of stea-
rine and elaine ; for the concrete part of fat is a combination of
the two with an excess of stearine, and the fluid part is a combi-
nation with an excess of elaine. The fat from the other animals
was then examined, principally with respect to their melting
point and their solubility in alcohol; the melting pomt was not
always the same in the fat ofthe same species of animal. When
portions of the fat of different sheep are melted separately at the
temperature of 122°, in some specimens the thermometer
descends to 985° and rises again to 102°, while in others it
descends to 104°, and rises again to 106°. A thermometer
plunged into the fat of the ox melted at 122°, descended to 98°5°,
and rose again to 102°. When the fat of the jaguar was melted
at 104°, the thermometer descended to 84°, and rose again to
about 85°; but a considerable portion of the fat. still remained in
a fluid state. With respect to the solubility of the different kinds
of fat in alcohol, it was found that 100 parts of it dissolved 2°48
arts of human fat, 2°26 parts of sheep’s fat, 2°52 parts of the
fat of the ox, 2°18 parts of the fat of the jaguar, and about
2:8 parts of the fat of the hog.
M. Chevreul next examines the change which is produced in
the different kinds of fat respectively by the action of potash.
All the kinds of fat are capable of being perfectly saponified,
when excluded from the contact of the air; in all of them there
:
/
|
.
1818.] their Combinations with Alkaties. 261
was the production of the saponified fat and the sweet principle ;
no carbonic acid was produced, and the soaps formed contained
no acetic acid, or only slight traces of it. The sapopified fats
had more tendency to crystallize in needles than the fats m their
natural state; they were soluble in all proportions in boiling
alcohol of the specific gravity of ‘821. The solution, like that of
the saponified fat of the hog, contained both the margaric and
the oleic acids. They were less fusible than the fats from which
they were formed; thus when human fat, after being saponified,
was melted, the thermometer became stationary at 95°, when
the fluid began to congeal ; in that of the sheep the thermometer
fell to 118°5° and rose to 122°; in that of the ox it remained
stationary at 118°5°; and in that of the jaguar at 96°5°.
The saponified fat of the sheep and the ox had the same
degree of solubility in potash and soda as that of the hog. »
100 parts of the fat of the sheep when 2 ,-.
saponified were dissolved by. ...... tort) OF -potalae
100 parts of the same were dissolved by 10°27 of soda.
100 parts of the saponified fat of the ox 2 45.49 o¢ potash
were dissolved by. .......0sceesee> P .
100 parts of the same were dissolved by 10°24 of soda.
100 parts of the saponified fat of the hog 2 j 5.04 o¢ potash
were dissolved by. ....020-00--220+
100 parts of the same were dissolved by 10°29 of soda
There is no carbonic acid necessarily produced in the saponi-
fication of the different kinds of fat ; for if we take two equal
quantities of the same solution of potash, and employ one of
them in the saponification of any species of fat, if we then
decompose the soap by the hydrochloric acid, we shall obtain a
quantity of carbonic acid equal to that which is contained in the
alkali that has not been employed in saponification. In order to
discover whether any acetic acid is produced in the saponifica-
tion of the fat of the human subject, of the sheep, and of the ox,
308-88 grs. (20 grammes) of ooh of these kinds of fat were sapo-
nified by pure potash ; the soap was decomposed by tartaric acid ;
the aqueous fluid was poured off and distilled, the product was
then neutralized by barytic water, and this was evaporated to
dryness in order to obtain the saline residuum. The saline
residuum from human fat was too minute to be sensible to the
balance ; it was observed that the aqueous fluid which proceeded
from the decomposition of a soap prepared from the fat of the
kidneys, and likewise from a soap prepared with the fat from the
breast of a female, had a strongly marked odour of cheese, a
circumstance which indicates the presence of the aroma of butter
in these kinds of fat; this principle is not, however, found in all
ee ePonnens of human fat, that from the thigh being entirely
without it,
262 M. Chevreul on Fatty Bodies, and [Ocr.
The saline residuum obtained from the soap of mutton fat
weighed -06 gr. ; but it seemed to contain a small portion of the
sweet principle. By adding phosphoric acid, a rank odour was
disengaged, mixed with that of acetic acid. The saline resi-
duum of the soap from the fat of the ox was in too small a
quantity to be appreciated, yet the aqueous fluid proceeding
from the decomposition of the soap was acid and amber coloured ;
the odour was precisely the same with that which is disengaged
from oxen, when they have been heated by exercise. The odor-
ous principle is more developed in the fat of the jaguar by being
saponified ; the odour is not easily defined, but 1s thought to
resemble that which is sometimes perceived in the menageries of
wild beasts. From these observations we may conclude, that
the action of potash develops in the fat of the sheep, the ox,
and even of the jaguar, odorous principles, which are analogous
to, if not absolutely identical with, those which the animals
exhale under certain circumstances, and that an acid property
accompanies these principles. { . j
The following table contains the proportions of the saponified
fat and of the matter soluble in water into which 100 parts of the
fat are capable of being changed.
Human fat.
Saponified fat. ...0...2.20+ 95
Soluble matter. ...-.eeeeees 5
Fat of the sheep.
Saponified fat + ......... «na, Srl
Satuble matter. weciccsacese. 49
Fat of the ox.
Saponiffed fat. .....-eesec 95
Soluble matter. ........... 5
Fat of the hog.
Saponified fat. ......... selon Srna
Soluble matter. ..........-- ina phe
The quantity of soluble matter in these cases was obtained by
calculation from the weight of the saponified fat, because it was
not possible to separate completely the former from a portion of
water and saline matter which-was combined with it. Thus the
syrupy fluid, which contained the sweet principle produced by
saponification, although evaporated until it began to be volati-
lized, always weighed more than the fat had lost of soluble matter;
for example, the syrup obtained from human’ fat weighed 9:4,
that from sheep’s fat weighed 8, while that from the fat of the
ox and the hog each weighed 8°6.
M. Chevreul next proceeds to a particular examination of the
soaps of fat and potash. The following was the method of analy-
1818.] their Combinations with Alkalies. 263
sis which was adopted: the soap, after being separated from the
mother-water, was dissolved in boiling water: by cooling and
rest a quantity of pearly matter was deposited, which is consi-
dered as a super-margarate of potash, and the fluid becomes
alkaline. It was filtered and neutralized by tartaric acid ; by
rest there was a new product of super-margarate, and a quantity
of alkali was set at liberty ; the same process as that employed
above was repeated until there was no longer a pearly deposit ;
an oleate of potash was then obtained, which was decomposed
by tartaric acid. By this process the soap was reduced to the
super-margarate of potash and the oleic acid. Our next object
is to examine the relative proportion of these two ingredients as
procured from the different kinds of soap. The super-margarates
were first very carefully prepared by frequent ablution in distilled
water and in alcohol, and they were then decomposed by the
hydrochloric acid in the manner that has been described above
as applied to the soap of hog’s-lard: the following results were
obtained :
Super-margarate of human fat.
Margaric acid. .... 91°8848 .......... 100-00
“gl age er ae hy SEPA Hi aictarete b ove 8°85
Super-margarate of the fat of the sheep.
Margaric acid. .... Peis she crsrats .- 100-00
IPOPARIE APs ata othe” Ld OS) AG J. aisee>, | OOO
Super-margarate of the fat of the ox.
Margaric acid... -91°925 4.0... . 100-00
DOLGSEF "ocbiats'oss hele OTE uae rene. 8-78
Super-margarate of the fat of the jaguar.
Margaric acid. .... Lg cake 4 sige ALGO"
OES pete TOD, shee PRO ION
Super-margarate of the fat of the goose.
Mfarcane acids o. sO O ak. tae eaicles = .- 100°00
POU near ig SOG texte Mae eee Oe
¢
The super-margarate of the fat of the hog is composed of 100
parts acid and 8°8 parts of potash, so that all these super-mar-
garates are analogous in their composition.
Equal proportions of water and of these super-margarates were
boiled together to observe whether they were acted upon in a
similar manner; and the principal difference that was perceptible
was the greater or less degree of semi-transparency of the solu-
tions. e super-margarate from the ox was less opaque than
that from the sheep, and this was less than that from the hog.
It is stated that a mixture of one part of this last super-marga-
rate with 10 of boiling water seemed to lose its transparency
264 M. Chevreul on Fatty Bodies, and [Ocr.
upon the addition of 18,190 parts of water ; from which it might
be inferred that a great mass of this fluid, at the boiling temper-
ature, may dispose the super-margarate to be reduced to the
neutral margarate and the margaric acid.
Boiling alcohol of the density of -832 dissolves the super-
margarates in all proportions, when they do not contain any
margarate of ime. The following experiment may be cited as
an illustration of this property: 20 parts of alcohol dissolve 50
of the super-margarate of the ox at the temperature of 140°;
the alcohol was then so far concentrated that the fluid was to
the super-margarate as one to six, yet no precipitate was formed.
If we compare the acids of the different super-margarates
together, we shall find that they are-all of a brilliant white
colour, insipid, nearly without odour, insoluble in water, and
soluble in all proportions in boiling alcohol. Their saturated
combination with potash is soluble in boiling water, and by cool-
ing is reduced to potash and an insoluble super-margarate. The
differences which they exhibit consist in their fusibility, and in
the disposition and size of the needles which are formed when
the margaric acid is suffered to cool on the surface of water.
The following is a more particular account of each of the indivi-
dual acids.
The margaric acid of man was obtained under three different
forms; i. In very fine long needles, disposed in flat stars ;
2. In very fine and very short needles, forming waved figures,
like those of the margaric acid of carcasses ; 3. In very large
brilliant crystals, disposed in stars perfectly similar to the mar-
garic acid of the hog. The thermometer plunged into these
last crystals in a state of fusion, sunk to 133°5°, and rose again
to 134°; the first crystals melted at about 132°.
The margaric acid of the sheep, when procured from the first
deposit of super-margarate which was formed in the soap, was
in the form of fine radiated needles ; the thermometer plunged
into it when fused, sunk to 139°, and rose again to 140°. The
acid which was procured from the last deposits of super-marga-
rate, crystallized in larger needles than the preceding, and melted
at 132°5°. The margaric acid of the ox crystallized in small
- radiated needles ; when it became solid, the thermometer rose
from 139° to 140°. The margaric acid of the jaguar crystallized
in small radiated needles ; it was fusible at 131:5°. The margari¢
acid Le goose crystallized in beautiful brilliant, narrow lamine,
like the margaric acid of the hog ; it melted at 131°. From this
statement we perceive that the margaric acids of the ox and the
sheep resemble each other the most nearly, as well in their form
as in the degree of their fusibility, that we may obtain the acids
of the human subject and the hog so as to exhibit similar proper-
ties, and that the acids of the jaguar and the goose very nearly
resemble them. The greatest difference in the degree of fusi-
bility is 9°. :
a 2
1818.] ree Combinations with Alkalies. 965
We next proceed to the consideration of the oleic acid.
M. Chevreul’s experiments on the oleate of barytes, in order to
determine the proportion of its elements, have finally induced
him to adopt the quantities of 100 parts of acid to 27 parts of
base as the most correct, and from these we conclude that 100
parts of the acid will neutralize a quantity of base that contains
2°835 parts of oxygen. This determination of the capacity of
saturation of the oleic acid is further confirmed by the oleate of
_ strontian and the sub-oleate of lead. The following table con-
tains the proportions in which barytes, strontian, and lead, com-
bine with the oleic acid.
Oleic acid of human fat.
Bary tes. Strontian. Lead.
Meidss.< 5 100-00. ves LOO OD - 100-00
BeBe 305 2600.2!) ASD Ss . 82-48
Oleic acid of the fat of the sheep.
Acid...... 100-00 ...... 10000 ...... 100-00
PR PIRREE 5 aloes 92O77 |i. 41a side PADBBs ny SHEL
Oleic acid of the fat of the ox.
Acid ..,.. 10000 ...... 100:00 ...... 100-00
PAAR’: oo 016) 23193 rate iow ote) MOA Lore, nccie . 81°81
Oleic acid of the fat of the goose.
Acid...,.. 100-00 ...... 100-00 ...... 100-00
FASS op minainihy 202 04a mo.mep's ADDS \eny vnc 81°34
Oleic acid of the fat of the hog.
Acid...... 100:00 ...... 100-00 ...... 100-00
| BINT Tiana vietephesl th TIS sc « win 81°80
M. Chevreul next gives an account of the analysis of fat by
alcohol. He observes that he has found it very important in the
prosecution of his experiments to employ alcohol of the specific
gravity of from 0-791 to 0-798, instead of an alcohol of 0-821,
which he had employed in his earlier experiments, because the
solvent power of alcohol over fatty bodies diminishes in an ex-
tremely rapid progression when it is combined with water, and
particularly from the specific gravity of 795 to -82]. In proof
of this position the following experiments are adduced : 100 parts
of boiling alcohol, of the specific gravity of 7908, dissolved 100
parts of the stearine of the sheep, and the solution was not satu-
rated ; 100 rm of boiling alcohol, of the specific gravity of
*7952, dissolved 16-07 of the same stearine ; 100 parts of boiling
alcohol, of the specific gravity of -805, dissolved 6°63 parts,
while 100 parts of boiling alcohol, of the specific gravity of -821,
dissolved only two parts.
The method of analysis employed was to expose the different
266 M. Chevreul on Fatty Bodies, and {Ocr,
kinds of fat to boiling alcohol, and to suffer the mixture to cool ;
a portion of the fat that had been dissolved was then separated
in two states of combination ; one with an excess of stearine
was deposited, the other with an excess of elaine remained in
solution. The first was separated by filtration, and by distilling
the filtered fluid and adding a little water towards the end of
. the operation, we obtain the second in the retort, under the form
of an alcoholic aqueous fluid. The distilled alcohol which had
been employed in the analysis of human fat had no sensible
odour; the same was the case with that which had served for
the analysis of the fat of the ox, of the hog, and of the goose.
The alcohol which had been employed in the analysis of the fat
of the sheep had a slight odour of candle-grease.
Examination of the alcoholic aqueous fluids. That from human
at exhaled an odour of bile similar to what was perceived from the
fat of the hog ; it produced a bitter yellow extract : the part pro-
cured from the first washing was alkaline, that from the last was
acid ; it also contained a trace of empyreumatic oil. That from
the fat of the sheep did not exhale the odour of bile, but it
produced an acid extract similar to the preceding. That from
the fat of the ov was red and alkaline; it contained a little
muriate of potash and muriate of soda. That from the jaguar
had a disagreeable odour ; it contained a yellow, bitter, oily
matter, and it was thought also a little acetic acid. That from
the goose only contained atrace of matter soluble in water, and
was completely without smell.
The varieties of stearine from the different species of fat were
found to possess the following properties. They were all of a
beautiful white colour ; entirely, or almost without odour, insipid,
and having no action upon litmus.—Sfearine from man. ‘The
thermometer which was plunged into it when melted fell to
105°5°, and rose again to 120°. By cooling the stearine crystal-
lized in very fine needles the surface of which was flat.—Stearine
of the sheep. The thermometer fell to 104°, and rose again to
109°5°; it formed itself into a flat mass; the centre, which
cooled more slowly than the edges, presented small and finely
radiated needies.—Stearine of the ox. The thermometer fell to
103°, and rose again to 111°; it formed itself into a mass, the
surface of which was flat, over which were dispersed a number of
minute stars visible by the microscope; it was slightly semi-trans-
parent.— Siearine of the hog. It exhaled the odour of hog’s-
lard when it was melted. The thermometer fell to 100°5°, and -
rose again to 109°5°._ By cooling, it was reduced into a mass,
the surface of. which was very unequal, and which appeared to
be formed of small needles. When it cooled rapidly, the parts
which touched the sides of the vessel had the semi-transparency
of coagulated albumen.—Stearine of the goose. The thermo-
meter fell to 104°, and rose again to 109°5°; it was formed inte
a flat mass.
1818.] their Combinations with Alkalies. 267
With respect to the solubility of these different bodies in
alcohol, 100 parts of boiling alcohol, of the specific gravity of
0-7952, dissolved
Of human stearine .............. 21°50 parts.
Of the stearine of the BREED» sntesre . 16:07
Of the stearine of the ox. ........ 15°48
Of the stearine of the hog ........ 18-25
Of the stearine of the goose ...... 36:00
Saponification by potash.
¢_ It was fusible at 123-5°;
i ; it crystallized in small
scrnepe| Tn fit, O89 { needles joined in the form
duced by sa- of a funnel.
. ponification, ne { The syrup of the sweet
{ Soluble matter. principle weighed 8°6; the
acetate 0°3.*
¢ It began to become
| opaque at 129°, and the
' : thermometer became sta-
('Saponified fat. 94:6 { tionary at 127-5°; it crys-
Stearine of : | tallized in small fine Ya-
the sheep. diated needles.
The syrup of the sweet
; ‘ principle weighed 8, the
Soluble matter. 5-4 acetate 0°6; ithad a rancid
odour.
{ Itbegan tobecome solid |
| at 129°, but it was not
: ] perfectly so until 125-5;
ekg Saponified fat. 95-1 { it crystallized in small
th needles united into flat-
Eon tened globules.
‘ The syrup of the sweet
Soluble matter... 4°9 { pine weighed 9-8, the
acetate, 0°3.
It began to grow solid
| at 129°, and the thermo-
: - g4-g74 meter became stationary
{ Saponified fat. 94 654 at 125°5°; it crystallized
Stearine of {in small needles united
the hog. into flattened globules.
4 The syrup of the sweet
| Soluble matter. 5-352 principle weighed 9, the
L kre aie 2 8
acetate 0:4.
* This means the salt which we obtain after having neutralized by barytes the
product of the distillation of the aqueous fluid which was procured from the soap
that had been decomposed by tartaric acid,
268 M. Chevreul on Fatty Bodies, and [Ocr.
It became solid at 119°;
j it crystallized in needles
ee. a f Saponified fat 94-4 [ant DT hes Re
the goose. }
(Soluble matter. 5°6 pe
funnel.
The syrup of the sweet
inciple weighed 82.
All the soaps of stearine were analyzed by the same process as
the soap of the fat from which they had been extracted ; there
was procured from them the pearly super-margarate of potash
and the oleate; but the first was much more abundant than the
second. The margaric acid of the stearines had precisely the
same capacity for saturation as that which was extracted from the
soaps formed of fat. The margaric acid of the stearine of the
sheep was fusible at 144°, and that of the stearine of the ox at
143-5°, while the margaric acids of the hog and the goose had
nearly the same fusibility with the margaric acid of the fat of these
animals.
Of the Elaines—They were all fusible at 59°; there was no
deposit from them after they had been kept for a month in closed
vessels; noné of them were acid. Human elaine is yellow,
without odour, specific gravity -913 ; elaine of the sheep is with-
out colour, has a slight smell of the sheep, specific gravity -916;
elaine of the ox, without colour, almost without odour, specific
gravity *913; elaine of the hog, without colour, almost without
odour, specific gravity 915; elaine of the jaguar, of a lemon
colour, odorous, specific gravity 914 ; elaine of the goose, of a
light lemon colour, almost without odour, specitic gravity -92°9.
Solubility of the different Elaines in Alcohol of “7952.
Human elaine: 11-1 gr. were dissolved by 9 gr. of boiling
alcohol; the solution began to become opaque at 170°5°.
Elaine of the sheep : 3°76 gr. were dissolved at the temperature
of 167° by 3-05 er. of alcohol ; the fluid began to become opaque
at 145°5°.
Elaine of the ox: 5°8 gr. were dissolved at the temperature of
167° by 4-7 gr. of alcohol; the fiuid began to become opaque at
145°5°.
Elaine of the hog: 11-1 gr. were dissolved at the temperature
of 167° by 9 gr. of alcohol; the fluid began to become opaque
at 143°5°.
Elaine of the jaguar : 3°35 gr. were dissolved at the temper-
ature of 167° by 2°71 gr. of alcohol; the fluid began to become
opaque at 140°,
Elaine of the goose: 11-1 gy. were dissolved at the temperature
of 167° by 9 gr. of alcohol, the solution did not become turbid
until 123-5.
Saponification by Potash—The determination of the soluble
matter which the elaines yield to water in the process of saponi-
1818.] their Combinations with Alkalies. 269
fication is much more difficult than the determination of the same
point with respect to the stearines. The stearines are less sub-
ject to be changed than the elaines ; it is less difficult to obtain
the stearines in a uniformly pure state; besides the saponified fats
of the stearines being less fusible than the saponified elaines, it is
more easy to weigh them without loss. The elaines of the sheep,
the hog, the jaguar, and the goose, extracted by alcohol, yield
by the action of potash,
Of saponified fat.......... 89 parts
Of soluble matter..... SPE I
The elaine of the ox extracted in the same manner yields
Of saponified fat.......... 92°6 parts
_ Of soluble matter. ........ 74
_ The memoir terminates with the following general conclusions.
The different kinds of fat, considered in their riatural state, are
distinguished from each other by their colour, odour, and
fluidity.
The cause of their colour is evidently a principle extraneous to
them, since they may be obtained colourless. It is the same
with respect to their odour; for if we do not always deprive
them entirely of it, we can remove a portion of it, which is suffi-
cient to prove that it must not be confounded with the fixed fatty
bodies from which it has been separated. The reduction of the
different kinds of fat into stearine and elaine explains the differ-
ent degrees of fluidity which they possess ; but it may be asked,
whether we ought to regard stearine and elaine as composing
two genera, which embrace various species, or as two species,
each of which may be absolutely represented by a stearine or an
elaine obtained from any one of the fats which have been
described above..
If the stearines and elaines are identical, they ought to exhibit
exactly the same phenomena, when they are placed in the same
circumstances, under all possible relations. They should have
the same external appearance, the same solubility in alcohol, the
same decomposition by potash, and consequently the margaric
and the oleic acids, and the sweet principle which they yield,
should be identical, and in the same proportion. Viewing the
subject in this manner, we may easily answer the question, for
we have only to examine whether the stearines and the elaines
actually present this identity of properties. Now we have
observed differences between the stearines when they have been
brought to the same degree of fusibility. Those of the human
subject, of the sheep, the ox, and the goose, coagulate into a
mass, the surface of which is flat ; that of the hog into a mass,
the surface of whichis unequal. The stearines of the sheep, the
ox, and the hog, have the same degree of solubility in alcohol ;
the stearine of man is a little more’ soluble, while that of the
270 M. Chevreul on Fatty Bodies, and [Ocr.
goose is twiee.as much so. The elaines of man, of the sheep,
the ox, the jaguar, and the hog, have a specific gravity of about
-915; that of the goose of about ‘929. The elaines of the sheep,
the ox, and the hog, have the’ same solubility in alcohol; the
elaine of the goose is a little more soluble. On the other hand,
the margaric acids of man, of the hog, of the jaguar, and of the
goose, cannot be distinguished from each other; those of the
sheep and the ox differa few degrees in their melting point, and
alittle also in their form. As for the slight differences which the
oleic acids present, they are not sufficiently precise for us to be
able to particularize them.
M. Chevreul’s Seventh Memoir.*
This memoir consists of three parts ; the first of which is on
spermaceti, or as M. Chevreul technically calls it, cetine. In
the fifth memoir, in which we have an account of many of the
properties of this substance, it was stated that it is not easily
saponified by potash, but that it is converted by this re-agent
into a substance which is soluble in water, but has not the sac-
charine flavour of the sweet principle of oils; into an acid
analogous to the margaric, to which the name of cetic was
applied ; and into another acid, which was conceived to be ana-
logous to the oleic. Since he wrote the fifth memoir, the author
has made the following observations on this subject: 1. That
the portion of the soap of cetine which is insoluble in water, or
the cetate of potash, is in part gelatinous, and in part pearly ;
2. That two kinds of crystals were produced from the cetate of
potash which had been dissolved in alcohol ; 3. That the cetate
of potash exposed, under a bell glass, to the heat of a stove,
produced a sublimate of a fatty matter which was not acid. From
this circumstance M. Chevreul was led to suspect that the
supposed cetic acid might be a combination or a mixture of
margaric acid and of a fatty body which was not acid ; he accord-
ingly treated a small quantity of it with barytic water, and boiled
the soap which was formed in alcohol; the greatest part of it
was not dissolved, and the alcoholic solution, when cooled,
filtered, and distilled, produced a residuum of fatty matter which
was notacid. The suspicion being thus confirmed, M. Chevreul
determined to subject cetine to a new train of.experiments, which
are now to be related. Being treated with boiling alcohol, in
the same manner with hog’s-lard, as mentioned in the third
memoir, a cetine was procured which was fusible at 120°, anda
yellow fatty matter which began to become solid at 89°5°, and
which at 73°5° contained a fluid oil, which was separated by
filtration.
Cetine in this state, fusible at 120°, was more sonorous, more
brilliant, and less unctuous than the spermaceti of the shops ; it
;
. Ba’
* Abstracted from Ann. de Chim, et Phys. vii.155. (Feb, 1818.)
1818] _—stheir Combinations with Alkalies. 971
had less smell, and was somewhat less soluble in alcohol; for
100 parts of alcohol of the specific gravity of :821 dissolved only
2:5 parts of it, while it dissolved 3-5 of the common spermaceti.
The solution was neither acid nor alkaline ; by cooling, it pro-
duced an abundant deposit of small pearly plates. The action of
potash upon the puritied cetine was then examined. As the
saponification of cetine is a tedious operation, and the potash is
apt to act upon glass vessels, a digester was employed, and
ri parts of cetine were added to the same quantity of potash,
dissolved in 100 parts of water. The ‘process was repeated 10
times upon the same materials, when the matter which remained
in the retort appeared to be completely saponified ; this was
added to the fluid that was distilled over, and the whiole was
mixed with a solution of tartaric acid. A watery fluid and a
fatty matter were thus obtained, the latter of which amounted
to 18-45 parts. . 1
The aqueous fluid was distilled, the product had only a very
slight odour; when neutralized by barytes it afforded.a minute
quantity of yellowish acetate, and by evaporation a portion of a
yellow, syrupy fluid was procured. The fatty matter from the
soap of cetine was of a lemon colour; after being melted at the
surface of water, its fracture exhibited a lamellated and shining
texture. It was subjected to a temperature of 131°; and when
the thermometer fell to 112° it began to grow solid, but it con-
tinued to fall to 102°, at which point the congelation was com
plete: when melted with water it congealed at about 111°:
100 parts of alcohol of the specific gravity of -817 dissolved 115
parts of the fatty matter; the solution remained transparent for
@ considerable time ; but after standing for 24 hours, it depo-
sited some very fine, brilliant needles; it strongly reddened
litmus, and the red colour was converted into a blue by the
addition of water.
A train of experiments was then entered upon to discover
whether the whole of the substance was in the acid or saponified
state ; the results of which indicated that the fatty matter con-
tained two substances, one which was acid; and another
which was not so; in order to ascertain the proportions in which
they existed, the substance was treated first with barytes, and
afterwards with successive portions of alcohol; and by separating
the portion which was soluble in this medium from that which
Was not so, it was found to consist of
TR a, lean at Doe SS 63°79
aE. TOY GOIN 6 ohn btw atin. 4 01 tO,
100-00
These two bodies were then examined separately. The acid
fat, after being melted, crystallized in small, radiated, yellowish
needles. It was completely soluble in the water of potash when
272 M. Chevreul on Fatiy Bodies, and [Ocr;
boiling, and much diluted ; as the solution cooled, it deposited
the pearly matter very copiously. By analyzing it in the same
way with the otherkinds of soaps, the same results were obtained ;
it was reduced into pearly matter and into a soap which was
very soluble in cold water; these were found to be the super-
margarate of potash and a soap composed of the oleic acid.
When a portion of the oleate of potash was decomposed by tar-
taric acid, an oleic acid was obtained, fusible at 64-5°, of a yellow
colour, soluble in all proportions in alcohol of the specific gravity.
of 821, at the temperature of 77°. The following is the compo-
sition of the oleates of barytes, strontian, and lead respectively.
Oleie BEI: « dcce'sicks se ciee ast VUL0U
Barytes. 5.64 puiade toy oh alla
RSDINELENAEE 5 rte alg 5, e,eleveca wiecm 23°18
Oxide of lead. .........2. 100-00
The fat which was not acid, after being kept for some days in
a closed vessel, impregnated the confined air with an aromatic
odour. It wascolourless, and semi-transparent like wax ; when
it was suddenly cooled on water, the upper surface was flat, and
did not present any appearance of crystallization; while the
lower surface, which lay upon the water, was deeply furrowed.
When it was broken, it appeared to be composed of brilliant
plates. A quantity that had been melted in a porcelain capsule
was slowly cooled, and the upper surface was then crystallized in
small needles which were united into stars. This substance
melted at 176°, began to be opaque at 134°5°, and was com-
pletely solid at 123-8° ; it was perfectly transparent as long as it
remained fluid. It appeared to be soluble in alcohol in all pro-
portions; the solution did not affect the colour of litmus. It
contained a small quantity of barytes in the proportion of -066
to 100. By digesting the fatty matter in successive portions of
alcohol, and examining the substance that was dissolved, it
appeared that this re-agent does not possess the power of decom-
posing the fatty matter.
This fatty matter was then added to an equal weight of potash,
dissolved in a large quantity of water, and subjected in the
digester to eight successive operations, when a fiexble sapona-
ceous substance was procured, of a light yellow colour, fusible at .
about 144°, and an alkaline liquor which did not contain any of
the sweet principle. This jleazble saponaceous substance was
decomposed, and was found to consist of the peculiar fatty
matter, which was not acid, described above, and potash, in the
proportion of 100 of the former to seven of the potash. When
one part of the substance had 40 parts of water added, it lost its
semi-transparency and its lemon colour by absorbing the water,
and the mixture became milky. After being macerated for three
hours, it was boiled, and a perfect emulsion was produced,
1818.] _ their Combinations with Alkalies. 273
which, when concentrated to half its volume, was covered with
little drops, of a yellow oily appearance ; these by cooling became
solid, absorbed water, and formed a thick, white, mucilaginous
fluid. This was diluted with a large quantity of water, and had
all the soluble part’ of it removed by repeated ablutions. The
insoluble matter resembled a gelatinous hydrate of alumine ;
when heated gently in a small capsule of platinum, it was con-
verted into a milky fluid, which was quickly covered with yellow
oily drops ; as the matter cooled, it resumed the form of an
‘opaque mucilage ; and by dissipating all the water, a substance
was obtained, which, when melted, resembled a yellow oil. This
was found to consist of a fatty matter, which, by the test of litmus,
appeared to be very slightly acid, and a minute quantity of potash,
in the proportion of 100 to 0°63. From this result, M.Chevreul
concludes, that the water had removed from the flexible sapona-
ceous matter a great part of its alkali, and an atom of saponified
fat ; and that the substance left after the washing, although it
contained very little potash, was capable of forming a mucilage
with water.
We now proceed to a more particular examination of the fatty
substance of the flexible saponaceous matter. This substance,
after remaining for some days in contact with water, did not
become mucilaginous ; it only absorbed a little of the water, and
became white. After adding some drops of potash, and expos-
ing it to a gentle heat, a mucilage was immediately formed which
was clotted, and not homogeneous, like that described above.
This want of homogeneity depended upon an excess of potash,
which, not having formed a union with the fatty matter, had
exercised such an affinity that it could no longer form a mucilage.
This is similar to the action of an alkaline water, which has not
the power of dissolving soap. What proves this to be the correct.
method of viewing the subject is, that if the clotted mucilage
be thrown bic a filter and sufficiently lixiviated, a residuum is
procured, which, when diluted with water, forms a homogeneous
mucilage ; the water which passed through the filter held alittle
wes in solution. This experiment decidedly proves that potash
is the cause of the mucilage which the fatty substance forms; but
it still remains to be determined whether this substance is united
to the alkalies by means of an acid fat, or of the oleic or mar-
garic acid united toa fat which is not acid, or if it possesses this
property without any addition.
n order to resolve this question, a portion of the fatty sub-
stance was boiled for the space of an hour with hydrate of
barytes ; the solid matter that was formed was dried, and added
to 15 times its weight of alcohol of the specific gravity of :791,
at the temperature of 53°5°; the fluid was filtered, and there
remained upon the paper some white flakes, which, after having
been treated with muriatic acid and washed with warm alcohol,
yielded barytes and an acid fat, fusible at about 68°, which,
Vou, XII. N° IV. S$
274 M. Chevreul on Fatty Bodies, and [Ocr.
formed with a weak solution of potash a perfectly limpid solu-
tion, and was reduced into the pearly matter and an oleate of
otash. The alcohol, which was separated from the flakes, and
which had dissolved the greatest part of the matter subjected to
its action, was evaporated; the residuum, still containing barytes,
was treated with cold alcohol, the solution, when separated by
filtration from some flakes of the soap of barytes which were not
dissolved, yielded a fatty matter which was free from barytes.
This matter was fusible at 125:°5°; by cooling it crystallized in
small radiated needles ; it was white, but when fluid, of a light
lemon colour. By being heated in a platinum capsule on the
sand-bath, it melted, and the greatest part of it was evaporated ;
by increasing the heat, it inflamed, and a little carbon was left,
which bummed, leaving a residuum too minute to be appreciated
by the balance. Alcohol of the specific gravity of -812 dissolved
it in all proportions at the temperature of 129°. The solution
had no action on litmus or hematine ; when cooled, it deposited
crystals which were not as brilliant as those of cetine. Cetine is
also much less soluble in alcohol; for five parts of alcohol of the
specific gravity of -791, which, when heated, dissolved 0°792
parts of cetine, deposited a great part of it at the end of 24 hours,
while the solution of this other substance did not become turbid.
Two equal portions of the fatty substance were taken ; one
-was put into pure water, the other into water slightly alkaline ;
they were digested durmg two hours, twice evaporated to dry-
ness, and the residue had each time water added.to it. No
mucilage was obtained by this process, and none was obtained
when the alkaline part of the second portion was replaced by pure
water, and when, by being melted several times in water, it was
obtained free from potash. The fatty matter kept in pure water
became white on its surface ; but after being exposed for a
moment to the sun, it became yellow and semi-transparent ; in
this state it melted without disengaging any water. Hence it
follows that the fatty matter fusible at 125:5°, which is obtained
from cetine by treating it with potash, is not acid, when it has
been purified by barytes and alcohol from a small quantity of the
margaric and oleic acids, and that it is not susceptible of forming
a mucilage with potash.
Having now observed the action of potash and of the saponified
part of the cetine upon the part-which is not saponified, our next
object will be to examine the action of the water of potash, and
of the margaric acid upon cetine. Eleven parts of margaric acid
which was fusible at 129°, and seven parts of cetine fusible at
118°5° were employed, this being nearly the proportion in which
the saponified and the unsaponified cetine exist in the cetine
which has been subjected to the action of potash: 16 parts of
water and 18 of potash were added. The mixture was heated,
and a gelatinous magma was formed; to this a quantity of water
was added ; it was boiled for some time, digested during two
1818.] their Combinations with Alkalies. 275
days, and again heated, when the following phenomena were
observed during the cooling.
At 212° the fluid was milky, without, however, exhibiting any
appearance of flakes ; at 150°5° it began to become transparent,
and flakes were visible in it: and at 140° its transparency was
much increased. It preserved its transparency to 132°5°, but
below this it gradually lost it, so that at 122° objects could not
be seen through it, and white flakes began to be formed in the
parts which cooled the most rapidly ; at 114:5° the fluid was so
viscid that it resembled a pearly jelly; and at 113° it was per-
fectly opaque. As it cooled still further it entirely lost its viscidity ;
and it is remarkable, that after being left for some days, it was
reduced to a solid mass, swimming in a perfectly transparent
fluid, exhibiting an appearance similar to that of blood after it
has separated into the coagulum and the serum.
The fluid was decomposed by tartaric acid, and there were
obtained an aqueous fluid which, after evaporation, yielded to
alcohol a small quantity of a syrupy matter, which was not
saccharine, and nearly colourless, and about 18 parts of a fatty
matter, fusible at 118°5°. This substance was treated with
water of barytes, and the soap that was formed was digested in
boiling alcohol, when the following results were obtained. 1.A
residuum insoluble in boiling alcohol, which, when decomposed
by muriatic acid, produced 13-89 parts of a fat which was com-
pletely saponified, fusible at 127°, and perfectly soluble in
potash ley. 2. A soap of barytes, which was deposited from
the alcohol as it cooled, and which, when decomposed by
muriatic acid, produced -205 of fat completely saponified, which,
added to the former quantity, made it 14-095 parts. 3. An alco-
holic fluid, which, after it had been separated from the preced-
ing soap, was distilled. The residue of the distillation, on being
cooled, contained an abundant precipitate ; by applyimg a gentle
heat the greatest part of the precipitate was re-dissolved; there
only remained 0-185 parts of the acetate of barytes, in the form
of small crystals ; but the author thinks it more probable that the
acetic acid proceeded from the alcohol that was employed than
from the cetine.
- The alcoholic fluid itself, when concentrated, yielded with
water a fatty matter, which had the following properties. It was
mi-transparent, and without colour; it became solid at 120°.
y slow cooling it presented the appearance of small needles
united in the form of stars on the surface ; its solution in alcohol
had no effect upon hematine or litmus. {[t appeared to bear a
strong analogy to the portion of the cetine which resisted the
action of potash; but its quantity was to the acidified part in
the Seti aie of 52:64 to 47-36, instead of the proportion of
36-2 to 63:79, which was obtained by directly treating cetine
with potash. The part which was not acid wag, therefore,
s2
276 M. Chevreul on Fatty Bodies, and [Ocr.
treated with its weight of potash in the digester, and the opera-
tion was repeated eight times: a flexible saponaceous mass was
obtained, which produced a fat that was treated with water
of barytes. The soap then produced was acted upon by alcohol,
and yielded ;
Acid fat, soluble at 116°5°.............. 0°82 parts
Fat, which was not acid, soluble at 123°5°. 2°62
3-44
By adding together the different products, we have the pro-
portion of acid matter 59:9, and of matter which is not acid.
40-1, a result which proves that when cetine is dissolved by the
alkaline margarate of potash, the cetine does not undergo all the
change which might be produced in it by pure potash.
M. Chevreul thought it desirable to repeat the preceding train
of experiments with a margaric acid which was procured from
some other substance besides cetine, because if it was found that
the two margaric acids acted in the same manner, it would indi-
cate a new point of resemblance between the substances. He
- accordingly added together 11 parts of the margaric acid from
the ox, which was fusible at 134°5°; seven parts of the sperma-
ceti of the shops, fusible at 111°; and 16 parts of water holding
in solution 18 parts of potash ; they were digested for some time
with 500 parts of water, and after being heated to 158°, a ther-
mometer was plunged into the mixture. The fluid was now
perfectly opaque and milky; at 147° it began to grow clear, at
140° it was semi-transparent, and at 138° perfectly transparent ;
at 131° it was again partially opaque, at 129° the pearly matter
began to be visible, at 127:5° it was no longer transparent, at
120° there was a great quantity of the pearly matter suspended
in it, and the fluid was considerably viscid : the opacity conti-
nued to increase as the temperature was lowered.
The saponaceous mass was then decomposed by muriatie
acid; 17-9 parts of a fatty matter were procured, which was
fusible at 117°; this was treated with water of barytes, and
the following substances were afterwards obtained: 1. 13-19
parts of an acid fat, fusible at 126°, which was formed from the
part of the soap that was insoluble in alcohol. 2. 0-423 parts of
an acid fat, fusible at 110°; this proceeded from the soap of
barytes which had been dissolved by boiling alcohol, and which
was deposited from it by cooling. 3. 4:287 parts of a fat which
was not acid, fusible at 111°. ‘This last product was treated with
potash, and the saponaceous mass which was formed was
decomposed by an acid; a fatty matter was thus obtained,
which was boiled with water of barytes, and then subjected
to the action of alcohol; the results were; 1. 1:192 parts of an
acid fat, fusible at 71-5°; 2, 3-095 parts of a fat which was nos
1818.] their Combinations with Alkalies. 277
acid, fusible at 123°5°. It appears then that in this process the
acid matter was to the matter which was not acid in the propor-
tion of 55°15 to 44°85.
The changes which take place in the transparency of the fluids
which have been described, in a range of not more than 10°, are
worthy of being noticed, as it may, perhaps, enable us to explain
by the laws of chemical affinity some of the phenomena which
are observed to take place in the fluids of living animals, and
which have been generally supposed to be independent of che-
mical and physical powers.
The existence of what was called the cetic acid was deduced
_ from the two following observations ; 1. That the saponaceous
mass resulting from the action of potash on cetine, diluted in
water at 176°, did not permit any of the fatty matter to separate
at the surface, so as apparently to prove that the fatty matter
had been completely acidified by the action of the alkali.
2. That litmus was not reddened by the alcoholic solution of the
insoluble matter which is separated when we treat the sapona-
ceous mass of cetine with water, a circumstance which seemed
to prove the absence of the super-margarate of potash in this
insoluble matter. The first of these observations has been better
explained on a different principle ; and it now remains to show
why the alcoholic solution of a substance, which certamly con-
tains super-margarate of potash, does not affect the colour of
litmus. When the true nature of this substance had been disco-
vered, it was at first supposed, that the fatty substance which
was not acid might be alkaline, and that it might neutralize the
excess of acid in the super-margarate of potash. This opinion,
however, M. Chevreul afterwards abandoned, and was induced
to ascribe the effects to the great concentration of the alcohol
which he employed. The following experiments were performed
in order to show that this was the true explanation of the facts.
In five parts of alcohol, of the specific gravity of -791, 0-02 of
the super-margarate of potash was heated; a solution was
obtained which did not yield any precipitate when it was cooled
to 86°, and which did not redden 0:26 parts of a watery extract
of litmus, containing 11 per cent. of solid matter, when added
to it drop by drop, and even when heated to the boiling point.
If five parts of water be afterwards poured into the solution, no
ere is produced, but the litmus acquires the red colour.
o render the experiment more striking, we may tinge the water
blue with litmus, to show that the effect cannot depend upon any
acid contained in the water ; if we then add 10 parts of water to
the red fluid, the super-margarate of potash will be precipitated,
and the litmus will resume the blue colour. The fact may be
explained upon the principle, that the excess of margaric acid
in the super-margarate of potash, when dissolved in alcohol of
the specific gravity of 791, is more strongly attracted by the
neutral margarate of potash than it is by the potash of the litmus,
~
278 | M. Chevreul on Fatty Bodies, and — fOer.:
which is not the case when the margarate of potash is dissolved
in alcohol of a specific gravity above 900.
This discovery induced M. Chevreul to examine what was the
influence which water exerts on alcohol of the specific gravity
of :791, holding the super-margarate of potash in solution. It.
was observed that when the watery extract of litmus is added to
a solution of the super-margarate in this kind of alcohol, a blue
precipitate is produced, which was not dissolved, even when the
alcohol was warm; for when it was filtered at the boiling heat,
blue flakes were left upon the filter, and the fluid passed colour-
less. In order to know the extent of this property of litmus, of
oeing insoluble in concentrated alcohol, 0:02 parts of margaric
acid were dissolved in five parts of alcohol of the specific gravity
of :791, to which was added 0:26 parts of the watery extract of
litmus, when the fluid immediately became of a reddish purple.
It was boiled and filtered, the fluid passed through of a red
colour, and there remained flakes of a deep red upon the filter.
As the insolubility of the litmus in alcohol does not prevent
the margaric acid which is dissolved in this fluid from taking
the potash from litmus, we may conclude that there is some
other power, besides its insolubility, which prevents the excess
of margaric acid in the super-margarate of potash, when dis-
solved in alcohol, from neutralizing the potash of litmus: this
power is supposed to be the affinity which absolute alcohol has
for fatty bodies in general. This affinity rapidly decreasing in
proportion as more and more water is added to the alcohol ; and
the affinity of alcohol for potash rather augmenting than diminish-
ing by the presence of the water, it may be supposed that.
absolute alcohol, when it dissolves the super-margarate of potash,
will tend to diminish the action of margarate of potash on mar-
garic acid less than diluted alcohol, which has less affinity for
the excess of margaric acid. Consequently this action of water
upon alcohol, joined to that which it has upon the extract of
litmus, determines the excess of margaric acid to leave the.
neutral margarate to combine with the alkali of the litmus,
These considerations on the mode in which litmus acts, lead to
the conclusion that its indications are relative only, and that we
cannot deduce any positive consequences from them until we
have taken into account the circumstances under which the
bodies are placed.
The second part of the seventh memoir of M. Chevreul is
on the oil of the Delphinus globiceps.*
The first chapter contains an account of the properties of the
oil. It was extracted by a sand-bath from the cellular texture in
which it was contained. It was of a light lemon.colour, its
odour is said to resemble that of fish combined with the smell of
leather soaked in fat; its specific gravity at the temperature of
* Ann, de Chim. et Phys. vii. 264, (March, 1818S.)
1818.] their Combinations with Alkalies. 279
68° was ‘9178. It was very soluble in alcohol ; 100 parts of this
fluid, of the specific gravity of *812, dissolved 110 parts of the
oil at the temperature of 158°; the solution remamed transparent
to 125°5° ; 100 parts of alcohol of the specific gravity of -795,
dissolved 123 parts of the oil at the temperature of 68°. This
great solubility distinguishes the oil of the Delphinus globiceps
from the different kinds of fat which were examined in the last
memoir. Neither the oil itself, nor its solutions in alcohol, have
any action on the tincture of litmus. 77-22 gr. (five grammes)
of the oil being digested with potash for 20 hours, were converted
into a saponaceous mass, the solution of which in water was not
perfectly limpid. This soap was decomposed by tartaric acid,
when an aqueous fluid and a fatty matter were obtained. The
aqueous fluid had a very strong acid odour, which was more
powerful when the fluid was evaporated. ‘The fixed residuum
was treated with alcohol; and when this was evaporated, it left
a red syrupy fluid, having a sweet, but at the same time, a very
disagreeable taste, which weighed 9°73 gr.
_ The fatty matter was nearly colourless ; it became fluid at
68°; when kept during three days at 62°5°, it deposited a con-
siderable number of crystals. Its odour was much more power-
ful than that of the natural oil; it had a fishy, and extremely
rank, disagreeable flavour. Alcohol dissolved it in all propor-
tions, and this solution strongly reddened the tincture of litmus.
It weighed 51°6 gr. Hence it follows that the oil consists of
Fatty, matterss.:. 02:04 + sialon ace 66°8
Substances soluble in water.......... ooc0
100-0
The small proportion of the fatty matter, the strong odour
which it developed during saponification, and which was pecu-
liarly powerful during the evaporation of the aqueous fluid,
induced M. Chevreul to suppose that the oil of the Delphinus
globiceps was analogous to an oil which he had discovered in
butter, and which he proposes to make the subject of a succeed-
ing memoir. The want of transparency in the solution of the
soap, as mentioned above, led him also to conjecture that the
soap might contain a matter which was not acid, analogous to
that of the soap of cetine, and that consequently cetine might
exist in the oil. The oil was, therefore, exposed to a temperature
from 40° to 50°, and crystals were formed which were separated
by the filter: the filtered oil, when exposed to the temperature
of 26°5°, produced new crystals which were likewise separated
from the uncongealed part of the oil.
_We begin by an examination of the crystallized part of the
oil of the Delphinus globiceps. After being carefully separated
from the fluid part of the oil, it was dissolved in boiling alcohol,
from which it was precipitated by cooling in the form of beauti-
280 M. Chevreul on Fatty Bodies, and [Ocr.
ful laminated crystals. They were further purified by a second
solution in alcohol and subsequent crystallization, and were then
compared with cetine. The two substances were found to crys-
tallize in the same manner, whether they were suffered to cool
slowly on the surface of water, after having melted them, or were
deposited from alcohol. A thermometer plunged into this crys-
stallme matter when melted stood at 115°5°, when it began to
become turbid ; at 111° there was a considerable degree of con-
gelation, but the process was not completed until it reached the
temperature of 110°. One hundred parts of boiling alcohol, of
the specific gravity of :834, dissolved 2-9 parts of the crystalline
matter of the Delphinus and three of cetine: neither of the solu-
tions had any action upon coloured re-agents.
About 0:9 parts of each of the two bodies were separately
boiled in double their weight of potash for 30 hours: the cetine
became united with the potash sooner than the other substance ;
indeed a part of it appeared to be incapable of saponification.
Yet when this part was digested in a platinum capsule with a
solution of potash for 15 hours, an homogeneous mass was
formed, although the fluid part did not become transparent.
Both the saponified spermaceti and the saponified substance
from the Delphinus were heated in a solution of potash, and in
both cases the fluids became transparent. After remaining at
rest for the space of a year, the fluids were found to have depo-
sited a considerable quantity of pearly matter: when they were
heated, the pearly matter of both of them disappeared, but more
slowly from the crystalline substance of the Delphimus than from
the cetine. The fluids, when concentrated, were mixed with
the tartaric acid ; from the crystalline matter of the Delphinus,
0°82 of a fatty matter, fusible at 104°, was obtained, and from
the cetine, 0°76 of a fatty matter, fusible at 100-5.
The two fatty substances were treated with the water of
barytes, and the soaps which were formed were then subjected
to the action of alcohol at the temperature of the atmosphere.
The results were as follows, from the crystalline matter of the
Delphinus: 1. A substance which was not acid, fusible at
116°5°, and weighing 0:151; 2. An acid substance, fusible at
113°, weighing 0°552, and which produced a large quantity
of pearly matter, when dissolvedin potash. There was obtained
from the cetine: ]. A substance which was not acid, fusible at
125°5°, and weighing 0-227; 2. An acid substance, fusible at
98°5°, seeing 0:385, and which produced much pearly matter
with potash, IM. Chevreul observes, that if these experiments
do not decidedly prove the perfect identity of the crystallizable
substance of the Delphinus and of cetine, they at least prove
their strong analogy, since potash only partially acidifies them.
We next proceed to an examination of the oil of the Del-
phinus, after the separation of the crystalline matter. Its colour
was a little deeper than that of the oil in its natural state ; its
1818.] their Combinations with Alkalies. 281
odour was more powerful ; it was perfectly fluid at 68°; at this
temperature its specific gravity was *924 instead of -917, which
was the specific gravity of the oil in its natural state.
One hundred parts of alcohol, of the specific gravity of 820,
dissolved 149-4 parts of the oil at the temperature of the atmo-
sphere ; at 127-5° the solution began to be turbid ; it was slightly
acid by the test of litmus, and the colour of the fluid was
converted into a blue by the addition of water, as if it had con-
tained an acid fat.. In order to determine whether this was
actually the case, or whether the acidity depended upon the
development of the acid which had been detected in the aqueous
fluid that was obtained from the soap of the oil, when it was
decomposed by the tartaric acid, as mentioned above, the oil
was treated with magnesia, because this base has the property
of completely neutralizing acids, and does not acidity fatty bodies
in the same manner with potash and soda.
About six parts of oil which were slightly acid were mixed
with two parts of caustic magnesia, and about 100 parts of
water ; when subjected to a gentle heat they formed a kind of
emulsion. More water was added, and the heat was increased;
the fluid was filtered while it was still warm, and was found to be
without acidity. Being evaporated to dryness, a residuum was
obtained of a red colovr, which had the odour of the acid refer-
red to above, and weighed 0:02. The residuum was composed
of this acid united to magnesia, and of the orange-coloured
matter. The compound of oil and magnesia was put upon a
moistened filter, in order to remove from it any water which it
might contain; it was then exposed to a gentle heat, and
treated with alcohol of the specific gravity of -791. The solu-
tion was concentrated and mixed with water; an oil was obtained
of an orange yellow colour, which at the temperature of 59°
concreted into a species of butter; it had lost some of its odour,
it had no action upon paper stained with litmus, nor did its alco-
holic solution affect the tincture of litmus. About 4-5 gr. of this
oil were burned, and left only atrace of residuum, which was too
small to be appreciated by a very delicate balance. It follows
from this experiment that the acidity of the oil of the Delphinus
depends upon the acid mentioned above, and not upon a proper
acidification of the oil itself.
Five parts of oil which was not acid were saponified by three
ieee of potash dissolved in water; the substances were kept
seated for 15 hours ; the saponaceous mass resulting from the
operation was then dissolved in water, but the solution was not
perfectly limpid. The soap was decomposed by tartaric acid,
and the aqueous fluid was separated from the fatty matter : these
two substances were then separately examined. The aqueous
fluid was distilled; when it was concentrated into the state of a
syrup» water was added, and the distillation was continued, until
| the volatile parts which might yet remain in the residuum were
driven off; the fluid, after bemg duly evaporated, was then
282 M. Chevreul on Fatty Bodies, and [Ocr.
treated with alcohol of the specific gravity of -791. this being
evaporated, left 0°562 of a sweetish syrup, containing the sweet.
principle, a little matter having the smell of leather, and an
orange-coloured principle, which existed in the oil before it was
saponified ; for at the instant that the water of potash came into
contact with the oil, its colour was converted into a brownish
orange, even before the saponification had commenced. Hence
the following conclusion is drawn, that the colouring principle,
which is found in the aqueous fluid, is not produced by the
action of the alkali, but that itis simply set at liberty, and that
it afterwards unites with the potash, which renders the presence
of it more obvious, by forming with it a compound of a deeper
colour. The greatest part of the colouring principle remained in
the aqueous fluid, for fins saponified fat had scarcely any colour.
The product of the distillation of the aqueous fluid was neutral-
ized by the hydrate of crystallized barytes; being then evaporated
to dryness, it left 1:73 of a dry residuum, composed of acid
0-937, and of barytes 0°793. This acid was named the delphinic
acid.
The fatty matter was then examined. At the temperature of
68°, a small portion of the fatty matter was congealed ; and at
50°, the greatest part of it, whilst the other part was perfectly’
fluid: it hada light yellow colour. The warm water with sala
it had been agitated had removed from it its odour of fish and
of leather, and there only remained the rancid smell of the sapo-
nified fat. Its specific gravity at 68° was *892: it was very
acid: 100 parts of it boiled with portions of water which con-
tained respectively 13°53 parts of potash and 9°5 of soda, pro-
duced solutions which were not perfectly limpid.
The fatty matter weighed 3:3 parts; it was digested with
water of barytes in excess; it was evaporated to dryness, and
the residuum was treated with cold alcohol of the specific
gravity of °791. By this means there was produced 0-715 of a
white fat, fusible at 82°5°, which did not redden the tincture of
litmus, and soluble in cold alcohol ; and 2°585 parts of an acid
fat, which remained in combination with the barytes, and which
had not been dissolved by the alcohol. This acid fat began to
congeal at 715°, and at 59° appeared quite solid.
In order to know more accurately the nature of the products
which have been described, 40 parts of the oil of the Delphinus
were saponified, and the soap was decomposed by tartaric acid.
The aqueous fluid was distilled, the product of the distillation
containing the delphinic acid was neutralized by water of
barytes, and then evaporated to dryness: the properties of the
delphinic acid and its combination with barytes will be more.
minutely described hereafter. The fatty matter which was
separated from the potash by the tartaric acid formed with the
water of potash a solution which was almost transparent, from) —
which a very brilliant pearly matter was precipitated : when this.
was collected upon atilter, a glairy matter was obtained, which.
1818.] their Combinations with Alkalies. 283
dried into a fat. varnish. This precipitated substance, and the
fluid which had been separated by the filter, were then examined’
in succession. 1. The precipitated substance was treated with
the hydrochloric (muriatic) acid; the fatty matter which it
yielded was successively subjected, first to the water of barytes,
and afterwards to alcohol; by this process there were obtained
anacid fat anda fat which was not acid.
The acid fat was fusible at about 104°; it was completely dis-
solved by a weak solution of potash. The solution that was
formed contained the margaric and oleic acids; it deposited a
pearly matter, the margaric acid of which was fusible at 122°,
but which, after having been treated by the water of potash,.
produced an acid which was fusible at 129°. The super-marga-
rate which it formed with potash, contamed, for every 100 parts
of acid, 8°89 of base: 100 parts of the same acid neutralized 27,
parts of barytes and 21 of strontian.
The fat which was not acid was fusible at 89°5°. It was boiled
and digested for 20 hours in the water of potash: there was pro-
duced a yellow flexible matter, and a mother-water, which did
not contain either any fatty matter or sweet principle. The
yellow flexible matter, after being washed in cold water, was
melted ; it contained 100 parts of the fatty matter and 4°8 of
potash. Being treated with boiling water in a retort, a very
small portion was carried into the neck, where it attached itself
under the form of a weak jelly, while the greatest part was melted
at the surface of the water. The matter which was thus washed
contained scarcely any alkali, as was proved by treating it with,
muriatic acid. The tat was fusible at 86°; when treated first
with barytes and afterwards with alcohol, there was obtained a
little acid fat, and a white fat which was not acid, fusible at 95°.
2. The fluid separated by the filter from the precipitated
matter was then examined. This fluid, which was slightly
turbid, was rendered completely transparent by being heated :
it was decomposed by tartaric acid. The fatty matter thus pro-
cured was treated with the water of barytes and with alcohol ;
by this process there were obtained an acid fat and a_fat which.
was not acid, ;
The acid fat was fusible at 70°, and completely soluble in the
water of potash: it was converted into supet-margarate of
5 and oleate of potash. The oleic acid thus obtained was
fluid at 59°, it had only a slight odour; 100 parts of it neutral-
ized 27°8 parts of barytes and 20°5 parts of strontian. The fat
which was not acid was fusible at 61°; it was boiled and digested
during 20 hours with the water of potash ; a saponaceous mass:
was obtained which was not separated from the mother-water.
This was deprived of the fatty matter, but it still appeared to
contain a little of the sweet principle. The saponaceous mass,
heated with water, did not form a transparent solution, but it
produced a fluid in which a portion of pearly matter was per-
ceptible, and which was covered with a pellicle. This fluid
|-
284 M. Chevreul on Fatty Bodies, and [Ocr.
treated by an acid produced a fatty matter which was converted
into acid fat, fusible at 59°, and entirely soluble in potash, and
into a fat which was not acid, fusible at 80°5°.
From these experiments we learn that the oil of the Delphinus
globiceps is converted by the action of potash into, 1. Delphinic
acid; 2. The sweet principle ; 3. Margaric acid; 4. Oleic acid;
5. A matter which 1s not acid, fusible at 95°; and 6. into a
matter which is not acid, fusible at 86.5°.
We now proceed toa more particular account of the delphinic
acid.* We have already had occasion to notice the combination
of this acid with barytes, and the proportion in which the
elements of this compound exist ; the following is the method in
which their proportion was ascertained. The delphinate of
barytes was dried, and then heated in a capsule of platinum ; it
exhaled a peculiar aromatic odow, which is compared to that
produced by the distilled butirate of barytes :+ the residuum
was neutralized by sulphuric acid: 0-216 parts of delphinate of
barytes yielded 0-150 of sulphate, which represent 0°099 of
barytes ; hence it consists of
Ate rcligte uty We Sete ie Ul fiteteteks. aed 100-00
Barytes , OO la T SIRS chal 84:61
216
As 84-61 parts of barytes contain 8°88 parts of oxygen, it fol-
lows that 100 parts of delphinic acid neutralize this quantity of
oxygen in salifiable bases.
After attempting different methods to separate the delphinic
acid from the barytes, the following method was adopted. An
aqueous solution of the delphinate of barytes was concentrated,
and put into a long tube which was closed at one end, and a
quantity of a strong solution of phosphoric acid was poured upon
it; the mixture was then left at rest for some hours, and the
following products were obtained; 1. An aqueous fluid contain-
ing the acid phosphate of barytes, mixed with a little delphinic
acid; 2. An oleaginous fluid lighter than the first; this was
separated by means of a small syphon, and was the pure del-
phinic acid.
The delphinic acid resembles a volatile oil; it is of a light
lemon colour, or even quite without colour, and has a very
powerful aromatic odour, analogous to that of cheese or strong
butter, or rather to the butiric acid ; when the odour was weak,
it resembled that of old oil from the Delphinus. It has a very -
sharp acid taste, which is succeeded by the ethereal flavour of the
rennet apple : it left a white spot upon the part of the tongue to
which it was applied. The delphinic acid moistened glass,
paper, and stuffs, like essential oils ; it left on the bodies to
which it was applied an extremely disagreeable odour, which it
* Ann, de Chim, et Phys. vii.367. (April, 1818.)
+ The butiric acid is to form the subject of a future memoir.
1818.] their Combinations with Alfalies. I85
was very difficult to remove, exactly similar to that of the oil of
the Delphinus. At the temperature of 57° it had the density of
“941; its boiling point was not ascertained. It is very soluble
in alcohol, and slightly so in water; these solutions produce a
deep red colour in the tincture of litmus.
The oleaginous delphinic acid was either an hydrate or an
hydrogenated acid; for 0-3 parts of this acid being put into a
small tube of glass with three parts of the yellow oxide of lead ;
and the tube, after being introduced into a receiver, being gra-
dually heated, there was produced 0-04 of a watery fluid which
had no action upon litmus paper, and at the same time an ethe-
real odour was disengaged. If we consider the oleaginous
delphinic acid as a hydrate, its composition will be
which contains 13-6 of oxygen; this may be considered as 14
the quantity of oxygen which the acid saturates in the bases,
since 100 of acid neutralize 8-88 of oxygen and 888 x 1-5
— Eos
The compound of delphinic acid and lead was then treated
with water, filtered, and evaporated ; the fluid was turbid, and
a quantity of delphinic acid was disengaged, which was percep-
tible by the smell : 0-190 parts of the acid, when well dried, was
put into a small capsule of platinum with diluted nitric acid, no
sensible effervescence was produced, but the acid odour was
perceptible. It was gently evaporated, the residuum was cal_
cined, and there was obtained 0-135 of a perfectly pure yellow
oxide of lead, entirely soluble in weak nitric acid. Hence it
follows that the delphinate of lead is formed of
PRCIGL oplein'» i eiales lp MOD Mathie oon, il OO
RIGS eiatare's an cies ies attack SALES
This contains 17-3 of oxygen, which is about double the quan-
tiry found in barytes, that is, 8°88 x 2 = 17-76: from this it
appears that the salt of lead evaporated to dryness is a subs
delphinate.
elphinic acid was neutralized by the water of strontian, and
evaporated to dryness : 0-200 parts of the salt were decomposed
by nitric acid; ‘the nitrate of strontian which was produced
formed 0-132 of sulphate, a quantity which represents 0:07656
of base. Hence we have,
ate a sss s'a's's 10844, 5%; VO ee: 100
Pas ee WOGO de kw. 62; this con-
tains 8-89 of oxygen.
_ The delphinic acid was then neutralized with sub-carbonate of
lime, and the product was treated in the same manner with the
286 M. Chevreul on Fatty Bodies, and [Ocr.
delphinate of strontian ; the result was 0-1170 parts of sulphate
of hme representing 00486 of base. Hence we have,
contains 90112 of oxygen.
The solutions of the delphinate of sirontian and of lime,
placed under receivers containing quick-lime, crystallized in long
prisms. The crystals of the delphimate of strontian became of
an opaque white, in consequence of their efflorescing. The
delphinate of barytes did not crystallize under the same circum-
stances.
After having thus made us acquainted with many of the proper-
ties of the delphinic acid, M.Chevreul proceeds to inquire, what
relation the oil of the Delphinus bears to the delphinic acid.
This is a question which he is not at present able to answer in a
satisfactory manner, because it would require the elementary
analysis of the oil and its acid, which has not been yet accom-
lished ; but the following points may be considered as esta-
lished. °
When the oil is treated with a base, which, like magnesia,
has a strong tendency to neutralize acids, without, however,
having the property of determining the transformation of a fatty.
body into the margaric and oleic acids, scarcely any delphinic
acid can be separated from the oil. In order to procure the
acid, the oil must be treated with a base which is sufficiently
powerful to transform a portion of it into the sweet principle, and
into the margaric and oleic acids. Without deciding whether
this acid be a product or an educt, it must be admitted that the oil
of the Delphinus contains a quantity of matter which experiences
the same change with the fatty bodies that have been described
in the earlier memoirs ; and besides this, a quantity of matter
which produces the delphinic acid.
From this result, it seems that we are acquainted with no
substances which more resemble the one in question than the
hydrochloric, acetic, and other ethers, which do not act upon
vegetable colours, but which, however, yield on analysis a con-
siderable quantity of carbon and hydrogen, besides the elements
of the hydrochloric and acetic acids. The volatility of the ethers,
compared to the fixedness of the oil, showd not be considered
as an objection to this analogy, since the volatility of ammonia is
not so to the analogy of this substance with the fixed alkalies :
it must, however, be observed that the analogy is in the first
case an analogy of composition, and in the second an analogy of
properties. If we are to expect any aid in the prosecution of
the science of natural history from chemical analysis, the com-
position of the oil of the Delphinus will be an object deserving
_our aitention, as it appears to be unlike any thing else with
which we are acquainted, except the oil of butter.
5
1818.] their Combinations with Alkalies. 287
We now come to the third part of the memoir, which treats of
the common fish oil of the shops.
It was of an orange brown colour, its odour a compound of
that of fish and leather prepared with oil, its specific gravity was
‘927 at the temperature of 68°. It remained fluid during several
hours at 32°; but after having been exposed for some days to
this temperature, a fatty concrete matter was deposited, which
was in very small quantity only, and was separated by filtration.
The oz that was left, after the separation of the concrete
fatty matter, was not acid by the test of litmus paper: 100 parts
of alcohol, of the specific gravity of 795, dissolved 122 parts of
the oil at the temperature of 167°; the solution began to be
turbid at 145°5°; it was not acid. It was treated with potash,
when placed under mercury out of the contact of the air: the
sweet principle and an acid fat were produced, but no carbonic
acid.
Two hundred parts were saponified by 120 parts of potash
dissolved in 400 parts of water: the saponification was easily
effected, and the soap, which was of a brown colour, was com-
pletely dissolved by cold water. It was decomposed by tartaric
acid, and there was obtained, 1. An aqueous fluid; and2. A
saponified oil. These two substances were each of them exa-
mined.
1..The aqueous fluid was of a deep brownish yellow colour,
and had the smell of leather. It was distilled, andthe residuum was
evaporated, and then treated with alcohol ; the alcohol dissolved
a sweet principle which was of a yellow colour, and had a very
pleasant flavour. The product of the distillation was acid; it
perceptibly held in solution an aromatic principle which had the
odour of leather. It was neutralized by the water of barytes, and
then distilled: the product was without smell. The residuum
weighed 0°3; it was the proper delphinate, from which the
delphinic acid might be obtained by means of the phosphoric
acid. With respect to quantity, this residuum was very differ-
ent from that which was obtained from the oil of the Delphinus.
2 The saponified fish oil had more tendency to crystallize than
the oil in its natural state. It was soluble in all proportions in
alcohol of -821; its solution contained the margaric and oleic
acids: 100 parts of this oil, when heated, were completely dis-
solved by portions of water which contained respectively 13-45
parts of potash and 9°15 of soda.
Twenty parts of the saponified oil were boiled with the water of
of barytes; the soap that was formed was treated with alcohol, but
scarcely any of the fatty matter which was not acid was procured.
The saponified oil was treated witha hot solution of potash, a little
more than was sufficient to dissolve it: the soap was diluted with
water; and after remaining some time at rest, a pearly matter
and an oleate were formed, which were successively examined.
The successive action of the water of potash much diluted
288 M. Chevreul on Fatty Bodies, and [Ocr.
and alcohol on the pearly matter proved that it contained a per-~
ceptible quantity of oleic acid; after this was separated, the
following results were obtained. The substance was very bril-
liant, and perfectly white ; it had only an extremely slight odour;
it was not dissolved in warm water, but it was completely soluble
in a solution of alkali. By cooling, this solution was converted
into potash and the super-margarate of potash, exhibiting all the
properties which had been formerly described as belonging to this
substance. By analysis, it yielded,
Margaric acid. ......++++ 100°00
Potash . ste es eeeeeenees 8:77
The margaric acid was almost without odour ; it crystallized
in small, fine, radiated needles. When melted at the temperature
of 158°, it congealed at 131° ; but as the bulb of the thermometer
was not completely covered in this experiment, and as the acid
was very turbid at 132°5°, probably this may be more exactly the
proper melting point.
The oleate of potash, after it had ceased to yield any more
pearly matter, was decomposed ; the acid was left at the temper-
ature of the atmosphere, and a crystalline substance was sepa-
rated. After this separation, the following properties were
found in it: it was of a brown orange colour, much deeper than
that of the oleic acids of the fat of the hog, the sheep, the ox,
&c.; but this colour probably depended upon something distinct
from the oil itself, whether proceeding from the decomposition of
a portion of the oil, or from some other cause. This oleic acid
had a strongly marked fishy smell, which it communicated to its
combinations with barytes, strontian, and the oxide of lead.
These oleates produced the following results by analysis.
CON Art a Rae 100-00
Ban UCES gars Brain a\e aes Ns 2 26°77
DiPON AM sss heels rele cee 19-4]
(Oxide GEAGAG:. |. 0 acu aietae te 81-81
We now come to the examination of the concrete fatty matter.
After being drained on bibulous paper, it was acted upon by
boiling alcohol, by which a considerable quantity of elaine was
separated; during this process the concrete matter became
coloured. It was then melted; a thermometer plunged into it
descended to 70°, and as it became solid, rose again to 80°5°.
The action of heat entirely removed from it the odour of leather.
Nine parts of alcohol, of the specific gravity of -795, dissolved
five parts of the concrete fatty matter. The solution yielded by
cooling, 1. Small radiated needles of the most beautiful white
colour; and, 2. Needles of a yellow colour: there remained a
viscid mother-water, of a brown colour; and it seemed as if in
this operation the colouring principle was increased in its quan-
2
1818.] their Combinations with Alkalies. 289
tity; whether it was really formed durmg the process, at the
expense of the fatty matter, or whether it was detached from
some substance which previously concealed its colour, it was
peculiarly developed by the action of potash. It was observed
that the process of saponification developed the leathery odour
which the substance had lost by fusion.
' 3°6 parts of the coloured fatty matter, having been saponified
by an equal weight of potash, produced a scap which was decom-
posed by tartaric acid. 1. The aqueous fiuid was distilled, and
the residuum was treated with alcohol. The alcohol dissolved
about 0°25 of a yellow syrup, the taste of which seemed at first
to be bitter and astringent, but afterwards became slightly sac-
charine. The product cf the distillation had a slight smell of
leather and a little acidity ; being neutralized by barytes, 0°03
of a salt was obtained, which had rather the smell of delphinic
acid than of leather.
2. The saponified fatty matter contained two substances,
which were easily separated from each other: the one which
was the most abundani constituted 3-06 parts; it was of an
orange yellow colour; the thermometer plunged into it, after it
was melted, fell to 79°5°, and rose again to 82°5°. This sub-
stance, which was very soluble in the water of potash, appeared
to M. Chevreul to be entirely formed of the margaric and oleic
acids. ‘The second substance, which constituted only 0-14 parts,
was brown, infusible at 212°, completely soluble in boiling alco-
hol, and left no fixed matter when it was incinerated. From this
experiment, 100 parts of the concrete matter contain
Fatty saponified matter............ foal Le Res
Matter soluble in water. ............ I]
100°0
The properties of the concrete substance which is separated
from the common fish oil seem to indicate that this substance
belongs rather to stearine than to cetine, or to the crystallized
substance which is obtained from the oil of the Delphinus. But
it is possible that this substance may not be essential to this fish
oil; and besides, it exists in so small a quantity, that its nature
could not be very exactly ascertained.
Upon the whole, we may conclude that the fish oil which was
examined resembles the oil of the Delphinus in its odour, but
that it differs from it, 1. In yielding only a trace of the volatile
oil after being sapomified; 2. In not furnishing any crystalline
substance analogous to cetine; 3. In its being more easily sapo-
nified than that substance, and without producing any matter
which is not acid; 4. In containing much more of the colouring
principle.
Besides the delphinic acid which exists in the oil of the Del-
phinus and in common fish oil, M. Chevreul thinks that we must
Vou. XLII. N° IV. >
290 M. Braconnot on Sorbic Acid. [Ocr.
admit the existence of another principle, which has a fishy odour,
and which he conceives to be identical with an odorous principle
which he has discovered in the cartilage of the Squalus peregri-
nus. This substance is peculiarly developed when it exists in
combination with ammonia or an ammoniacal salt, and the salt
is mixed with caustic potash. It may be doubted, whether the
leathery odour of the saponified oil of the Delphinus and eommon
fish oil, and the colouring principle which exists in so consider-
able a quantity in these oils when they have been long kept, are
proximate principles simply disengaged, or the result of some
alteration which the principles that were extracted from these oils
have undergone, or depend upon some other principles which
have hitherto escaped detection.
4
ArTICLE VI.
On the Sorbic Acid and its different Combinations. By M. Henri
Braconnot.*
Tue author had been led to conclude that malic acid, as it is
usually obtained, is not pure, and had attempted to obtain it
from the malate of zinc, a substance said by Scheele to form
very beautiful crystals ; but he found that the acid thus procured
differed essentially from the malic. He.was endeavouring to
ascertain the exact nature of these differences, when Mr. Dono-
van announced his discovery of the sorbic acid: M. Braconnot
objects to the method adopted by Mr. Donovan, both as being
one by which the acid is obtained in small quantity only, and in
an impure state. M. Braconnot recommends the followin
rocess : the fruit of the Sorbus Aucuparia is to be taken before
it is quite ripe, and is to be bruised in a marble mortar and
strongly squeezed. It must then be boiled, and carbonate of
hme must be gradually added until all effervescence ceases ; it
is then to be evaporated to the consistence of a syrup, the froth
being carefully removed as it continues to form. The sorbate of
hime is quickly precipitated in the form of a granulated salt ; the
supernatant fluid is to be poured off, the salt washed in cold
water, and dried with a linencloth. The salt has a slight yellow
tinge, which indicates that it is not pure; it is, therefore, to be
boiled for a quarter of an hour, with an equal weight of erystal-
lized sub-carbonate of soda diluted with water, A neutral sorbate
* Abridged from Ann. de Chim, et Phys. vi. 239, It is probable that the expe-
riments of M. Braconnot and those of M. Vauquelin are to be regarded as equally
original, and that they must have been performed about the same time, M. Bra-
connot’s paper was read to the Royal Society of Sciences at Nancy, in November,
1817; and M. Vanquelin’s paper was published in the number of the Ann. de
Chimie et de Physique for the following month.
1818.] M. Braconnot on Sorbic Acid. 291
of soda is thus procured, which is soiled by a red colouring
matter, to remove which it must be warmed for some minutes
with lime water, or cream of lime, which will remove the colour-
ing matter, and leave the sorbate of soda untouched. The
liquor must then be filtered, and will be found to be limpid and
colourless; pass through it a current of carbonic acid gas to
separate the lime which it may contain ; the sub-acetate of lead
is then to be added, which will form a very white precipitate of
the sorbate of lead, from which, after having well washed it,
the-'sorbic acid must be disengaged by diluted sulphuric acid
assisted by heat. By this process, M. Braconnot informs us
that the sorbic acid may be obtained in a perfectly pure state ;
itis uncrystallizable, and attracts moisture.*
With respect to the characters of the sorbates, M. Braconnot
observes, that the tartrates are the vegetable salts which bear
the strongest analogy to them; from their property of combining
with an excess of acid which, in most cases, diminishes their
solubility. But as the two acids differ in their power of crystal-
lizimg, we may lay it down as a general principle, that when the
tartaric acid forms a salt that is only slightly soluble with any
base, the sorbic acid will forma crystallizable salt with the same
base ; and whenever a tartrate shall be uncrystallizable, by a still
stronger reason the sorbate of the same base will be so peewee,
In the formation of the sorbates, 100 parts of sorbic acid
saturate a quantity of base which contains about 11 parts of
oxygen. Tartaric acid has a greater capacity for saturation;
according to Berzelius it is 11‘94, while he estimates that of
citric acid at 13-588, that of acetic acid at 15°43, and that of
oxalic acid at 22:062. The sub-sorbates contain a quantity of
acid, double of that which is contained in the neutral sorbates.
All the sorbates swell up by heat, and generally are disposed to
attach themselves to the vessels in which they crystallize. The
sorbates of potash, soda, and ammonia, are uncrystallizable and
very soluble. M. Braconnot formed a neutral sorbate of lime,
by pouring muriate of lime into the solution of sorbate of soda ;
it was in the form of transparent, granulated crystals, which are
not affected by the air, and contain no water of crystallization.
{t requires for its solution 147 parts of water, at the temperature
of 53°5° Fahr.; and less than 65 parts of boiling water. It is
composed of
Sorbic acid . RAGS ais nied Piouwohe awl ne ee BOD
Ne uli s dsl eile OMe ch Libehieealt BOBO
100+
* We have it not in our power to decide upon the respective merits of the pro-
cesses of Mr. Donovan and M. Braconnot; but we may observe that Mr: Donovan's
succeeded in the hands of M. Vauquelin,—Ep.
+ This differs a little from Vauquelin’s estimate.—Ep,
72
292 M. Braconnot on Sorbic Acid. fOer.
M. Braconnot also formed an acidulous sorbate of lime, by
dissolving the neutral sorbate in sorbic acid. This salt presents
prismatic crystals, with six faces; it is very acid, and requires
for its solution no more than 50 parts of water at the temperature
of 53:5°. It is composed of
Sorbic acid ... 65°48 ........ 84:63 ........ 100°000
TAME, cobs ealeieg, LA Os e.sibi fein > ded 2 nee eS
Water . PERT
100-00 100-00
M. Braconnot has procured three sorbates of zinc, a neutral
sorbate, a super-sorbate, and a sub-sorbate. The neutral sor-
bate is formed directly by combining the sorbic acid with the
oxide of zinc, or in decomposing the sorbate of lime by sulphate
of zinc. Itis composed of |
Sorbie-acid'os «2 58:06 cn 0.8 645 V8.5 168-000
Oxide of zinc. .. 31:95 ...... SSDs oe ee 26
Water sihiec. 4: 10:00
100-00 100-0
The super-sorbate is prepared by dissolving neutral sorbate of
zine in sorbic acid, and washing the crystals in alcohol or in
water. It contains
Sorbicgeid. 4 oho TBR oc: oe dese Vea
Quidetabebineschun GHG Fe Rae
Whater: hac beets :
100-00 100-00
- The sub-sorbate of zinc separates naturally from the watery
solution of the neutral sorbate ; it is insoluble in boiling water,
and consists of
ACID Geiuta, dis) ewbey ie Serr ys 51:89
Oxide) of zine dy. incinge have 48°11
100-00
M. Braconnot has examined the sorbate of lead ; he finds that
there is no super-sorbate, and that its solution in water does not
redden litmus. By examining the crystallized sorbate of lead,
well dried, and afterwards calcined in a platinum crucible, he
estimated that it was composed of
SNOPES CMe ao 57 03.10 OSs y las ixla'te ne sive voip OOD
Oxidewrieads? 276115 666.0050. 3.. 1S
1818.] M. Vauquelin on Sorbic Acid. 293
If the sorbate of lead be obtained by double affinity, it affords
different results ; in this case it consists of
POLDIC ACIC., as/cittetomisies aaa WOR TEE
Oxide Of lead. . o.c ss biuciiie n/a
—_—_——-—
100-00*
M. Braconnot is, however, inclined to suppose that the salt
obtained by double decomposition is a mixture of the neutral
sorbate and the sub-sorbate, because the oxygen in the oxide
of lead which saturates 100 parts of sorbic acid is 11:253 accord-
ing to the first analysis, and 14-7 according to the second.
Sub-sorbate of lead may be procured by digesting ammonia upon
the neutral sorbate of lead ; the sub-sorbate does not forma hard
or granular mass with boiling water, as is the case with the
neutral sorbate. M. Braconnot has also formed the sorbates of
strontian, barytes, magnesia, alumine, and the protoxide and
deutoxide of mercury, of silver, copper, iron, manganese, and
tin; these salts are very soluble, uncrystallizable, and deliques-
cent.
—— Ea
Experiments on the Sorbic Acid. By M. Vauquelin.+
In the year 1816 Mr. Donovan discovered in the fruit of the Sor-
bus Aucuparia a new acid, possessed of specific properties ; and
also announced that this acid exists in other vegetables. M. Vau-
quelin has repeated the experiments of Mr. Donovan; he has
confirmed the discovery of the new acid, and has made a number
of observations upon it, which had not been noticed by the
discoverer.
The author began by obtaining a very large quantity of the
juice of the ripe Sorbus, no less than 50 quarts. The juice,
when recently procured, is viscid, so as to pass with difficulty
through a filter; but by remaining for about a fortnight in a warm
temperature, it experiences the vinous fermentation. It then
becomes bright and clear, easily passes through the filter, while
a quantity of yeast is separated from it. By distillation, a
portion of alcohol, of a specific odour and flavour, may be pro-
cured from the fermented juice, whence it is inferred that the
recent juice must have contained saccharine matter. The sorbic
acid itself does not appear to be affected by this fermentation.
No malic acid could be detected in the recent juice of the sorb,
The viscidity of the recent juice did not appear to depend, in
* The estimate agrees very nearly with Vauquelin’s, who also formed his sor-
bate of lead by precipitation.—Ep.
+ Abridged from Aun. de Chim. et Phys. tom. vi. p. 337. (Dec. 1817)
t The readers will observe that M. Vauquelin differs from M. Braconnot in
employing the fruit in its ripe state; it remains to be determined whether this
circumstance was the difference which was observed between the substance as pro-
cured by these chemists—Ep,
294 M. Vauquelin on Sorbie Acid. [Ocr.
any degree, upon jelly mixed with it, but upon asubstance more
analogous to vegetable gum. The juice of the sorbus, after
fermentation, still contains a red colouring matter, which passes
to a violet purple by the contact of tin, and which becomes a
greenish yellow by the action of alkalies. The juice also con-
tains a very acrid and hot principle, which has some analogy
with that which we meet with in Pyrethrum ; it is soluble both
in water and in alcohol, and is always accompanied by a brown
and bitter substance. The berries of the sorb, after being bruised
and expressed, retain a yellow matter, which may be separated
‘by warm alcohol, or ether, and which seems to have some
resemblance to a resin; it is principally attached to the paren-
chymatous part of the fruit. é
The recent juice of the sorb is of a red colour, and of a very
acid flavour, mixed with a degree of bitterness. When the
carbonate of lime is added to it, an effervescence is excited ;
but whatever quantity we employ, the fluid always continues
acid. If this solution of the super-sorbate of lime be poured off,
and the carbonate of potash added, a brisk effervescence takes
place, and a white powder is precipitated, which consists of
neutral sorbate of lime: 100 parts of the precipitated sorbate of
lime, when well dried, were decomposed by heat, and appeared
to consist of
Ad eipindeenk beak Clarke on the + [Oer:
colour. By means of nitric acid the sorbic is converted into the
oxalic acid; nitrous gas and carbonic acid are disengaged.
From this, as well as from its properties generally, M. Vauquelin
concludes that the sorbic acid is the one which approaches the
most nearly to the malic.
For the purpose of analyzing the sorbic acid, the deutoxide of
copper, and the sorbate of lead, both well dried, were heated
together in the apparatus contrived by Prof. Berzelius. One
gramme (15°444 grs.) of the sorbate of lead were mixed with
five times its weight of the oxide of copper ; and two grammes
(30°888 ers.) more of the oxide were used to cover the mixture.
One hundred and seventy cubic centimetres of gas were pro-
cured, which being totally absorbed by potash must have been
carbonic acid. The loss of weight in the apparatus was 800
milligrammes. The quantity of acid contained in the sorbate of
lead must have been, according to this analysis, 330 milligrammes.
From these data we learn, that the sorbic acid is composed of .
2 LEAL i) CRP ARE Pa i 16:8
DETDOM Gs Selma eee = sha 9 Weir re ELD
L009: 8 Fe reve We OPM PERE De 54:9
100-0
With respect to the relation which the constituents of the acid
bear to each other, they appear to be nearly as the numbers
one, two, and three, ‘The relation which exists between the
quantity of oxygen in the acid and that of the bases which it
saturates 1s as four to one. As the pure sorbic acid appears to
be without odour and without colour, and of an agreeable flavour,
the author suggests that it might be substituted for the tartaric
and citric acids in medicine and the arts,
Artic.teE VII.
On the colouring Constituent of Roses, and of the Flowers and
Leaves of other vegetable Bodies. ina Letter to the Editors.
By Edward Daniel Clarke, LL.D. Professor of Mineralogy
in the University of Cambridge, &c.
(Continued from No, 11, Vol. xii. p. 128.)
GENTLEMEN,
In the conclusion of the thirteenth article of your number for
August, 1 promised to continue my observations upon the
colouring constituent of vegetables, and to ascertain, if possible,
whether this principle ought in every instance to be ascribed to
iron. ‘The presence of 2ron in those bodies will, perhaps, appear
to be evident when | have communicated the result of a few
-1818.] colouring Constituent of Roses. 297
subsequent experiments; and if it, be considered how very
inconsiderable a portion of this metal communicates a blue
colour to the sapphire and a red colour to the ruby, it is hardly
ossible to conceive that any notable portion of it can exist
m the flowers and leaves of plants without being manifested by
some of the various hues by which the metal is characterized in
its different combinations, when acted upon by light, heat, and
atmospheric air.
Before I proceed to detail any of these experiments, it 1s proper
to notice some very powerful objections which have occurred
- respecting the presence of iron in the precipitate which I ob-
tained from the énfusion of roses, by means of ammonia, as men-
tioned in my last; of which I transmitted a portion to you, and
to other eminent chemists, soon after the publication of my
former letter. This precipitate was found to burn to a white ash,
in which no portion of iron could be detected sufficiently consi-
derable to entitle it to the distinction of a colouring agent ; and
hence it was inferred, as a probable conjecture, that the metallic
iron, which I sent also to you, was due to the prusszated alkali
used in the experiment. Jn answer to which, it may be urged
that we must cease to employ this re-agent as a test of the pre-
sence of iron, if the mere touch of a glass rod, dipped in a solu-
tion of prussiate of potass, be capable of communicating such a
considerable portion of the metal, to fluids before destitute of it,
as to account for the metallic and magnetic beads exhibited to
you, and which were obtained from such inconsiderable volumes
of asolution as test-tubes are fitted to contain. But 1 trust I shall
be able to show, that the iron is really due to the vegetable infu-
sion to which it was ascribed ; having, by means of other tests
and other experiments, not liable to these objections, obtained
the same results; not only from the petals of roses, but from the
leaves of plants, and from flowers of all colours. It must
remain, therefore, for your chemical readers to determine,
whether tron, existing under such various modifications, and
differing only ax to its quantity, however decisively its presence
may be demonstrated, ought to be considered as having any
connexion with the colour of the vegetable in which it resides.
(A.)—The colouring principle in vegetable extracts, whatever
be its nature, being soluble im water, as admitted by Chaptal,*
and also by Thenard,+ with whose observation I terminated the
last communication 1 made to you upon the subject, | resolved
- to try an experiment with the petals of the damask rose, using
no other solvent than water. For this purpose, | made an infu-
sion, by boiling distilled water in a Florence flask, and pouring
it, in a boiling state, upon a quarter of a pound of the dried petals,
* “ Nothing more is necessary than to infuse these substances in water, for the
parpose of extracting their colouring principle.’”’"—Chaptal’s Chemistry, vol, iii.
151, London, 1795, *
+ Traité de Chimie, tome troisieme (1716), p. 376. Paris, 1815.
; 1
298 Dr. Clarke on the {Ocr.
which I left in a porcelain vessel for several hours. Afterwards
collecting the clear infusion which had assumed a deep red
colour, | submitted it once more ina Florence flask to the heat
of an Argand lamp, and evaporated the whole to dryness.
There remained, at the bottom of the flask, a black carbonaceous
substance which had the smell of burned sugar. A portion of
this substance being placed within a cavity scooped in astick of
charcoal, was exposed to the action of the common blow-pipe ;
and, as it fused very readily, it was soon reduced to a very small
black bead ; which, resisting the utmost action of the blow-pipe,
was held for a considerable time in a state of fusion, attended
with phosphorescence and ebullition. After bemg cooled, its °
form was perfectly globular, and it was attracted and taken up
by a magnet. It was then hard enough to be driven into the
end of a deal splinter, and filed. Particles with metallic lustre
were by this means rendered conspicuous. I have sent one of
these beads to you for examination, corresponding in appearance
with the tron I before transmitted to you, and having the same
magnetic character. But in other trials, made with the same
carbonaceous substance, sometimes I obtained the black magnetic
beads, and at other times, owing to causes I am unable to
explain, it burned to a white ash, containing no magnetic particles.
The same substance being exposed to the action of the gas
blow-pipe, exhibited combustion with minute sparks, and was
speedily converted into a white opaque glass ; probably owing to
a portion of dime which has been detected in the precipitate
thrown down by ammonia from the znfusion of roses, as described
in my last letter; and which acting as a solvent for the colouring
maitter,* may, perhaps, explain the presence of a metallic oxide
in the vegetable.
(B.)\—The magnetic beads, mentioned in A, being dissolved in
acids, and the acid, in every instance, evaporated to dryness,
and distilled water added, and afterwards filtered, tincture of
galls threw down a dark precipitate ; and prusstated alkali, a
deep emerald green precipitate ; the latter, collected on a filter,
became afterwards blue.
(C.)—The precipitates mentioned in B exposed to the action
of the common blow-pipe upon charcoal, were again converted into
beads acting upon the magnet; and after admitting the action of
the file again, disclosing a metallic lustre. Exposed to the gas
blow-pipe, combustion with scintillation ensued, as in the com-
bustion of particles of zron.
(D.)—The presence of tron appearing to have been thus satis-
factorily ascertained in the carbonaceous substance obtained by
the evaporation to dryness of an infusion of roses, as related in
A, some of this substance was triturated in a porcelain mortar,
and being reduced to a fine powder, was boiled in diluted
* See Chaptal, vol. iii. p. 154.
1818] colouring Constituent of Roses. 299
muriatic acid. The acid being then filtered, was evaporated,
with gentle heat, to dryness; and distilled water afterwards
added and filtered. The surface of the clear filtered liquor was
now touched with a glass rod, dipped in tincture of galls ; a pale
whitish precipitate appeared which, upon warming the liquor,
became chocolate brown, and afterwards black. Some of the
same liquor, in a separate vessel, touched with a glass rod dipped
m a very diluted solution of crystallized prussiate of potass,
instantly exhibited an abundant blue precipitate.
From the foregoing observations, it is plain that the petals
of red roses contain tron; and, perhaps, the medical virtues
ascribed to the infusion of roses, if they exist at all, may be due
to the very inconsiderable portion of the metal present in the
infusion. We all know how very insignificant are the chemical
constituents of many chalybeate waters, destitute of which their
salutary properties no longer characterize them ; and also that
when art attempts to supply what Nature has thus sparingly
afforded, the same deficiency ensues.
Afterwards I submitted other vegetable bodies to a similar
investigation, and found evident traces of zron, although not
always in equal quantity, in the petals of blue, yellow, and white
flowers, and in the green leaves of several plants, especially mm
the petals and leaves of centaurea cyanus, verbascum thapsus, phlox
paniculata alba, alcea fici folia, &c.&c. White flowers contain
the smallest portion of the metal ; and its exhibition is more diffi-
cult during their examination than in other instances. Infusions
made of the green leaves of the fig-tree are sometimes used, when
highly concentrated, to remove grease spots from black cloths
and stuffs. I examined an infusion of this kind made with dis-
tilled water, two quarts of it being reduced by boiling, in giass
vessels, to a pint. From this infusion, a single drop of tincture of
galls immediately threw down a whitish precipitate, which sepa-
rated and became darker by being heated; and when collected ona
filter was found to contain iron. Ammonia caused a more copious
precipitate of the same nature, but of a mud colour; and this
also contained iron. The same results were obtained in the
examination of an infusion, similarly made, of zvy leaves. The
most remarkable results, as being, perhaps,: the most satisfac-
tory, were obtained from a concentrated infusion made with the
green leaves of the hilium tigrinum, or tiger lily. From this in-
fusion, a gallate of tron was instantly separated, simply by touch-
ing the surface in a test-tube with a glass rod dipped in tincture
of galls, and afterwards heating the infusion to the boilmg point.
Ammonia, being substituted for the tincture of galls, threw down,
as before, a more copious precipitate containing iron.
I remain, Gentlemen, yours, Xc.
Cambridge, Sept. 15, 1818. Epwarp DANIEL CLARKE.
300 Mr. Gill on Improvements in Printing. {Ocr:
ArticLe VIII.
On Improvements in Printing. By Thomas Gill, Esq.
(To the Editors of the Annals of Philosophy.)
No. 11, Covent Garden Chambers,
GENTLEMEN, Sept. 14, 1818.
Havine had my attention directed lately to the important arts
of letter-press and copper-plate printing, and having obtained a
knowledge of several new and useful improvements therein, I
shall make no apology for communicating them to the public,
through the medium of your Annals.
The improvements made in the typographic art by the late
Earl Stanhope, and particularly in forming the press of that
unyielding substance cast iron, instead of the elastic materials
before used, in making the platten and table with truly plane
surfaces, and in working the screw by a combination of levers,
has given the means of taking off an impression from a much
larger surface at once than could ever be done with the old
presses ; and the art of making paper by machinery in long con-
tinued sheets has also afforded another important aid to this
object.
This increased size is, however, attended with the inconve-
nience of causing much greater labour to the pressmen ; and it
has accordingly been the study of. several ingenious mechanics
to cause'the press to be worked with more ease, and particularly
to introduce other contrivances in place of the screw, which,
although a powerful agent, moves with very great friction.
Mr. Medhurst was, I believe, amongst the first to substitute
another movement, which, however, has never been brought
into general use; Mr. Ruthven constituted a new combination
of levers; and Messrs. Cogger and Scott, circular inclined
planes ; and lately an alteration of Mr. Medhurst’s contrivance :
still, notwithstanding all these endeavours, a great exertion of
human strength is required in working these presses.
I am, however, glad to state, that this evil is now in a very
great degree alleviated, by the introduction of the Columbian
press, invented by Mr. George Clymer, of Philadelphia, several
of which are now in use in different printing establishments of
this metropolis with very great advantages indeed in point of
power and ease in working over other presses.
Printing by machinery is also making considerable progress
in this country, particularly by Mr. Kcenig’s machines at Messrs.
Bensley’s, Messrs. Taylors’, and the Times newspaper printing
offices, and by Messrs. Applegart and Cowper’s new invented
machine.
We are at present, however, outdone by our trans-atlantic
competitors, insomuch that the Bible is now printed in North
1818.) Analyses of Books. 301
America in the very short period of three minutes! This is effected
chiefly by the employment of cylinders covered with stereotyped
plates, a contrivance which I invented, and endeavoured to get
carried into effect in this country upwards of eight years since,
and which at length is now, I believe, introducing here by
degrees.
Mr. Donkin has much improved the machine for printing by
means of types fixed upon the flat sides of revolving polygons,
originally invented by Mr. Wm. Smith, the geologist, and Mr,
Bacon, of Norwich ; and particularly by the introduction of a
permanently elastic inking roller, the composition of which is
also substituted in other printing houses in the forms of balls and
rollers, with very considerable advantages over the usual balls,
which, as is well known, are covered with sheep’s skin, prepared,
and kept in a state of use by a peculiarly offensive process.
I am happy in being enabled to add, that the health and com-
fort of persons employed in the very laborious business of
copper-plate printing may now be very much promoted by the
adoption of an improvement recently made by Mr. Ramshaw, of
‘Fetter-lane, and for which he has been very deservedly honoured
with the gold Isis medal of the Society of Arts, namely, in heat-
ing the copper-plates by means of steam, supplied by one boiler
only to many cast iron receptacles with flat tops, on which the
plates are laid, and heated with great convenience and uniformity
to receive the ink, instead of employing as many open vessels
with charcoal constantly burning in them, which, besides
destroying the oxygen of the atmospheric air, producéd much
carbonic acid gas, and consequently very much injured the health
of the pressmen, enfeebled them, and rendered them much more
liable to ruptures from the violent exertions they are obliged to
make in that laborious employment. 1am, Gentlemen,
Your most-obedient servant,
THomaAs GILL
ArTIcLE IX.
ANALYSES OF Books.
Journal of a Residence in the Island of Iceland during the Years
1814, 1815, &c. By Ebenezer Henderson.
_ Tue main object of Dr. Henderson’s visit to Iceland was to
superintend the distribution of a number of copies of the Scrip-
tures, provided for the use of the inhabitants by the British and
Foreign Bible Society. For this purpose he made the tour nearly
of the whole coast, and crossed two or three times the dreary
uninhabitable wastes that occupy the interior of the country.
He thus had an opportunity of examining a much larger portion
of the island than has fallen under the notice of any modern
302 Analyses of Books. {Ocr.
traveller ; and although not, strictly speaking, a man of science,
has collected much new and interesting matter relative to its
mineral history. The following summary of his observations on
this subject will, it is hoped, prove acceptable to the readers of :
the Annals.
From Reykiavik, the capital of the island, Dr. H. undertook
three distinct journeys. In the first, he proceeded to the Gey-
sers, then crossing the interior of the island ina N.N.E. direction
he arrived at the head of the Eyafiord on the north coast ;
thence, after a short excursion to the west, he proceeded along
the coast in an easterly direction, visited the volcanic neighbour-
hood cf Mount Krabla, traversed the eastern part of the island,
and returned to Reykiavik along the whole of the southern coast.
His second journey included nearly the whole of the western
coast, together with such parts of the north-western as were
aceessible ; and on his return he traversed the interior of the
island somewhat to the east of the parallel of Reykiavik. The
third journey included the tract between the two former ones.
The central parts of Iceland appear to be wholly uninhabited
except by a few roving banditti, the existence of whom, how-
ever, of late years, is rather suspected than ascertained. Plains
of loose volcanic sand, black rough ridges of lava many miles in
length, deserts of loose stones and clay, deeply ploughed by
torrents of hot and of cold water, which, during the tremendous
convulsions to which the island has been subject, have descended
with irresistible fury from the snows and glaciers of the usually
inactive volcanoes, cones of a black or lurid red colour exhaling
sulphureous vapours, jets of steam and of boiling water, the roar-
ing rush of which is almost the only sound, except that of the
tempest, which wakes the echoes of these forlorn solitudes—
such is the scenery which composes the interior of the country
as far as it is known to the inhabitants of the valleys and of the
coasts. Patches of coarse grass and herbage, at intervals of six
to 20 miles, just sufficient for a day’s sustenance to a score of
horses, afford the possibility of traversing these deserts during a
few weeks in the summer. The following extract from Dr. Hen-
derson’s journal presents the whole scene in all its shuddering
reality.
““ Next morning we were under the necessity of prosecuting our journey, the
horses having eaten all the grass in the vicinity during the night, and we had a ride»
of more than 30 miles to the next station. During the first three hours, we had
rather a tedious ride up thesteep ascent covered with broken lava, which extends
along the west side of the mountain till we gained its summit, called Blafells-hals,
where there is a passage between that mountain and the immense chain of ice-moun-
tains in the interior. From this elevation we had a most commanding prospect
of the whole level tract of country, which, beginning at Haukadal, and stretching™
past Skalholt, opens into the extensive plains between Mount Hekla and the sea.
Several miles behind Thingvalla lay the large volcanic mountains called Skialdbried
and Tindafiall ; and between us and this latter mountain a regular chain of high
conical mountains commenced, which stretched to a considerable distance along the
base of the neighbouring Yikul. The blackness of their appearance formed a
perfect contrast to the whiteness of the perennial snows behind them. What par-,
1818.] Henderson’s Journal of a Residence in Iceland. 303
ticularly struck us was the majesty of the vast ice-mountain, which extends from a
little to the east of Tindafiall, in a westerly and northerly direction, to the dist-
ance of not less than 100 miles across the interior of the island.
** Descending by the west end of BlAfell, which here consists of immense irregular
masses of dark brown tuffa, we came again, in the course of a short time, to the
Hvit4, near its egress from a large lake, to which it gives the name of Hvitarvatn,
The whole of the western margin of this lake is lined with magnificent glaciers,
which, before meeting the water, assume a hue of the most beautiful green. It
abounds with excellent fish, and used to be much frequented in former times by the
peasauts in the south, At the fording-place, the river may be about 100 yards
across; and we found it in some places so deep, that our horses were on the point
of swimming. It is certainly the most formidable river in this quarter of Iceland;
and is often unfordable for weeks together, when travellers, coming from the de-
sert, are not unfrequently reduced to great straits, by the consumption of the
food they had provided for their journey.
** On leaving the Hvita, we encountered a long tract of volcanic sand, with here
and there insulated stones, of an immense size, which must have been erupted from
the Kerlingar-fialla volcanoes, situated at the distance of 15 or 20 miles in an east-
erly direction. Most of these volcanic mountains form beautiful pyramids, and
some of them are of a great height, and partially covered with snow. The cone, in
the remote distance, is most perfectly formed, and is quite red in appearance,
arising from the scorie deposited on its sides. None of these volcanoes have ever
been explored ; nor have I so much as met with their names in any description of
the island that [have seen, From the peasant at Holum, who has proceeded seve-
ral times to the vicinity in search of moss, I learned that a very extensive tract of
lava stretches between themand the ancient road, called Spreingi-sand ; and at one
place he observed much smoke, which he supposed arose from springs of boiling
water.
“« At four o’clock we came to the Black River (Svarta4), fording which we fell in
with an extensive tract, known by the name of the Kialhraun, which has been
at least twice subjected to fiery torrents from a volcano in the neighbourhood of
Bald-Yokul, if not from the Yékul itself. This lava is upwards of 20 miles in
length, and in some places five or six in breadth, Here the road divided: that
called Kialvegur, leading to Skagafiord, lay to the left, across the lava; whereas
the way to Eyafiord, which we pursued, ran along its eastern margiu, now on one
side of the Black River, and now onthe other, After travelling about eight miles
farther, over a very stony tract, we came to the station of Grananess, which we
found to be the termination of a very ancient stream of lava, mostly covered with
moss and willows, and having only a little grass in the cavities, which have been
formed by the bursting or falling in of the crust. Inhospitable as it appeared, we
were obliged tostop, as we were exposed to a heavy rain, and the next green spot
was about 50 miles distant.
**On the afternoon of Monday, the first of August, we commenced the worst stage
on our whole journey. Our road, which at times was scarcely visible, lay along
the west side of the Hof, or Arnarfell Yokul, a prodigious ice mountain, stretch-
ing from the volcanoes above-mentioned, in a northerly direction, for upwards of 50
miles, when it turns nearly due east, and extends to nearly 30 miles in that direc-
tion. We rode at no great distance from it for the space of 20 hours, and were all
the time exposed to a cold piercing wind which blew from that quarter. About
il at night wecame to the Blanda, or Mixed River, the waters of which were of a
bluish colour, and, dividing into upwards of a dozen of branches, they rendered
our passage both tedious and troublesome. Near the north-west corner of the
Yokul, a great number of curiously shaped hills presented themselves to our view,
which we found, on approaching them, to be partly volcanic and partly immense
masses of Yokul, intermixed with drosses and fragments of lava, which have beeu
separated from the mountain during some of its convulsions, and hurled along to
their present situation by the inundations it has poured down upon the plains. At
*10 minutes before three o’clock in the morning, as we had got quite surrounded by
these hills, and were almost shivering with cold (the waters being covered with fresh
ice), we were gratified with a view of the sun, rising inall hisglory directly before
us. The gloom in which we had been involved now fied away; and we obtained
a very extensive prospect of the surrounding country, It wasa prospect, however,
by uo means pleasing ; for to whatever side we turned, nothing was visible but the,
devastations of uncient fires, or regions of perpetual frost.”
304 Analyses of Books. [Ocr.
The middle part of the north coast appears to be by far the
most fertile ; the rivers are larger, the vales broader, the inter-.
mediate country less rugged ; and the Yokuls, or snowy moun-
fains, are removed to a great distance in the interior. The last
remains of the forests of Iceland are in this tract; but they are
now fast disappearing in consequence of the improvident
destruction made among them by the inhabitants, and the sup-
posed increasing inclemency of the seasons. Stumps of birch
trees more than two feet in diameter are still to be met with.
The N.E. quarter of the island is one of the chief volcanic
centres, and at present yields nearly the whole of the ‘sulphur
which is annually exported from Iceland. The hot springs of
Reykiahverf exhibit appearances similar, but inferior in magni-
ficence to those of the geysers in the south-west of the island,
and, therefore, need not be presented to our readers. But the
description of the scenery in the vicinity of Krabla, the principal
volcano of the district, forms, perhaps, the most interesting por-
tion of Dr. Henderson’s book, as far at least as the natural
history of the country is concerned.
‘ From the little port of Husavik the travellers proceeded in a
southern direction till they came upon the Lax4rdal, a rugged
valley filled with lava, through which the Laxa pursues its irre-
gular course. After passing a few miles over the rough lava,
they arrived on the edge of a desert, four hours’ journey across,
consisting of sand, pumice, and other volcanic substances,
wholly destitute of water and of vegetation. Beyond the sand
extends a prodigious stream of lava, being one of those which
issued from Krabla between the years 1724 and 1730, and inun-
dated nearly the whole of the plain along the northern and
eastern shores of the lake Myvatn. It still retains the orginal
freshness of its appearance. In colour, it is as black as jet; the
blisters and cracks by which its surface is diversified are of
enormous size, and most of the chasms are completely glazed,
and present the most beautiful and grotesque stalactitical masses.
At Reykiahlid, one of the farm-houses, over-run by the fiery
deluge, but which was afterwards rebuilt on nearly the same
spot, the travellers encamped for the night. The view from this
place is in an extreme degree savage and desolate. In front is
the Myvatn, or Gnat-lake, and the whole of the intervening
tract is one vast field of black, rough, and cavernous lava, pro-
jecting a considerable way into the lake, and forming innumer-
able creeks and promontories along the greater part of its
northern margin. To the north-west rise a number of barren.
hills that open into the sandy deserts, leaving which, the eye
wanders over an extensive tract of moor, intersected by red
conical mountains, till, reaching the south side of the lake, it falls
in with several huge mountains of singular forms, and the Namar,
or sulphur mountains, from which a vast profusion of smoke is _
constantly ascending, The most profound and death-like silence
1818.] Henderson’s Journal of a Residence in Iceland. 305
pervades the whole of this desolated region. The gloom of the
lake is greatly augmented by the small black islands of lava with
which it is studded; and the pillars of vapour ascending in
different parts from the surface of the water remind the observer
that the destructive element, which has been the tremendous
cause of the surrounding ruin, still lingers there, and may again
wake to activity. The lake is reckoned to be about 40 miles in
circuit, but is shallow from the floods of lava that have been
poured into its basin.
The next morning they resumed their journey towards the
sulphur mountains, passing over considerable tracts of lava and
volcanic sand, till having arrived in their immediate vicinity, the
increase of the exhalations, and the heat and unsoundness of
the surface, obliged them to advance with caution over the more
indurated parts. With all their care, the feet of their horses
occasionally broke through the crust, forming holes through which
the vapour issued in great abundance. On either side lay vast
beds sPatulpinn, covered with a thin crust, composed of aluminous
efflorescences, which being removed, a thick bed of pure sulphur
appeared, through which the steam issued with a hissing noise.
The sublimation of the sulphur is caused by the ascent of this
vapour, and its abundance and purity depend considerably on the
porosity of the subjacent soil. The tract which goes by the name
of the Sulphur Mountain is about five miles in length and one
mile in breadth, extending between the volcanoes of Krabla and
Leirhnukr, and joining the ridge by which these two mountains
are connected. The surface is very uneven, displaying large
_banks of red clay and sulphur, the crust of which is variegated
with tints of blue, yellow, and white.
After overcoming with great difficulty the labour, and escaping
the dangers of the ascent, they arrived suddenly on the edge of
an abrupt descent of more than 600 feet, at the bottom of which
lay a row of 12 large cauldrons of boiling mud, roaring, splashing,
and sending forth immense columns of dense vapour. By a cir-
cuitous route, among numerous boiling hot quagmires, they at
length arrived close to the sprmgs. Excepting two which lie a
short distance from the rest, they are all crowded into one Vast
chasm in the lava, Some of them remain stationary, but roar
terribly, and emit much steam; others boil violently, and splash
their black muddy contents round the orifice of the pit, while two
or three jet at intervals to a height of from five to 15 feet.
From this extraordinary scene they passed along the margin
of a stream of lava, covered with pumice and volcanic sand to
the base of Krabla; and with much difficulty succeeded in mak-
ing their way over the pumice sand and slippery clay which form
the side of the mountain. After an hour’s climbing, they arrived
at a vast hollow, forming the remains of the crater, in the middle
of which lay a circular pool of black liquid matter at least 100
feet in diameter. Nearly about the centre of the pool is an aper-
ture from which a vast body of fluid, consisting of water, sulphur,
Vox. XII, N° IV. U
306 Analyses of Books. [Ocr
and black clay, is thrown up, and which is equal in diameter to
the column ejected by the great Geyser at its strongest eruptions.
The height of the jets varied greatly, rising on the first propul-
sions of the liquid to about 12 feet, and continuing to ascend, as
it were, by leaps till they gained the highest point of elevation,
which was upwards, of 30 feet, when they again abated much
more rapidly than they rose. While Dr. Henderson continued
there, which was about an hour, the eruptions took place every
five minutes, and lasted about two minutes and a half.
From Krabla Dr. H. proceeded to the eastern extremity of the
island, whence he returned to Reykiavik along the southern
coast ; and in so. doing passed along the narrow and dangerous
tract, extending between the sea and the Yokuls, orice moun-
tains, which occupy the whole interior of the island in this
uarter.
The Yokuls are mountainous tracts, varying considerably in
elevation, almost the entire surface of which is covered with
snow and glaciers. Being perfectly desert, the remote parts of
scarcely any of them have been explored; but where they come
in contact with the cultivated or inhabited districts, their mis-
chievous and often fatal effects are but too well known. The
glaciers of the Alps, according to Saussure and other accurate
observers, are often found to encroach somewhat on the adjacent
lands and then to retreat, partly in consequence of the vicissi-
tude of the seasons, and partly from the accumulated pressure
of the water from the melting of the snow filling the crevices in
the ice, loosening more or less its adhesion to the subjacent rock,
and pushing before it the mass of the glacier till the water has
discharged itself by means of the numerous outlets thus formed,
when the glacier again retracts and withdraws nearly to its
accustomed limits.
The above phenomenon, which in Switzerland is in. general
little more than an object.of philosophical curiosity, is in Iceland,
especially on the southern coast, the occasion at all times of
reat inconvenience, and occasionally of horrible. devastation.
he cause of this is in part the enormous accumulation of snow
and ice which takes place during the winter in these high lati-
tudes, but principally the circumstance that the mountains on
which these glaciers rest are volcanoes. Hence, even in quiet
years, the melting of the ice is much more rapid in some parts
than in others, and this melting begins from the bottom of the
superincumbent mass of ice, which, being thus undermined, sub-
sides with a loud crash, sending forth long cracks in every direc-,
tion, and pouring out torrents of water, the impetuosity of which
bears down huge stones and blocks of ice into the rivers, thus
stopping for a time, or rendering excessively dangerous all pas-
“sage at the fords. In the mean time masses of the glacier, some
. miles in extent, begin to move forward into the plain, pushing
before them rocks of considerable magnitude ; and in the course
of a few months will advance half a mile or more, after whic,
1818.] Henderson’s Journal of a Residence in Iceland. 307
they retract, but seldom so far as to recover their original situa-
tion, leaving a face of rock or a waste of stones on which no soil
can ever after accumulate, and which, therefore, is lost to the
inhabitants. The following was the appearance of Breidamark
Yokul.when Dr. Henderson passed by it.
*¢ All along the margin, and a considerable way back, were deep indentations,
and, in some places, chasms of an immense size, that penetrated further than the eye
could reach, and in which I could hear the distant dashing of the water as it fell
from the surface of the Yékul. The margin consisted, for the most part, of large
flat pieces of ice lying in all directions: sometimes it was as perpendicular as a
wall; at others, the ice lay horizontally, forming vast crys(al grottoes; and, what
particularly struck me, was a number of small cavities and cells, in such parts of
the surface of the ice as were not exposed to the sun, which were filled with the
most beautiful pyramidic crystals, from a quarter of an inch, to an inch and a half
in diameter. In some places, the interior of the grottoes was completely studded
with these crystal groups, sparkling with a dazzling lustre, and assuming various
hues, according as they were more or less exposed to the light.
** Towards the bottom of the slope, the ice has collected so much sand and clay,
that if assumes a black and dark grey colour: higher up, where the heat of the sun
has less influevce, the winter snows remain undissolved, and give the Yékul a whiter
appearance; and, what is remarkable, at some distance from the margin, a vast
number of round pillars, resembling sugar-loaves, only more pointed at the top,
begin to rise above the surface, and extend back to the regions of snow. They are
quite black in appearance, and may be from three to 20 feet inheight. Where
the Yékul has pushed forward in one direction and again receded, large heaps of
clay, sand,.and turf, are thrown up, so as to form a catenation of small hills round
its base; but whereits progress is continuing, no such hills are seen; only furrows
are laid open in thesand, by the sharp projecting pieces of ice, and the sand is
raised, precisely as the ground by a plough, to either side. In some places, I could
Plainly observe the motion of the sand; but whether it arose from the actual pro-
gress of the Yokul, or merely from thedissolution of theice, I shall not determine.”
Occasionally the Yokul volcanoes wake to activity, and then
the destructive effects of an ordinary volcano are combined and
heightened tenfold by the immense deluges of cold and of hot
water which are then produced. Four times during the last
century, namely in 1727, 1753, 1755—6, and 1783, has this part
of the island been thus desolated. With the following descrip-
tion of the last. of these awful visitations, we shall conclude our
extracts from this interesting work.
** About a month previous to the commencement of the eruption, a submarine
voleano burst forth at the distance of nearly, 70 miles ina south-west direction from
Cape Reykianess in Guldbringe Syssel, and ejected such an immense quantity of
pumice, that the surface of the ocean was covered with it to the distance of 150
miles, and the spring ships considerably impeded in their course.
_“* The Skaptér volcano, so called from the river of the same name, down which
i inghe part of the lava was poured, is situated close to the eastern boundary
of West Skaftafell’s Syssel, about 32 British miles due north of Kyrkiube Abbey,
and near the contiguous sources of the rivers Tiina, Skaptd, and Hverfisfliot. It
lies principally in the valley called Varmardal, and consists of about 20 red coni-
cal hills, stretching in nearly a direct line, from E,N.E, to W.S.W. which have
served as so many furnaces, from which the melted matter has been discharged into
the valley. From these craters the lava has flowed which inundated the low coun-
try, through the channel of the Skapt4. What flowed down the Hverfisfliot, has
had its source in some other craters situated further to the north-east, but which are
evidently connected with the former hills, and would, in all probability, have
poured their contents down Varmardal, had it not been completely tilled with the
lava, which had already been emptied into it.
“From the Ist to the 8thof June, 1783, the inhabitants of West Skaftafell’s
Syssel were alarmed by repeated shocks of an earthquake, which, as they daily in-
creased in violence, left no reason to doubt that some dreadful volcanic explosion
u2
308 Analyses of Books. [Ocr.
was about to take place. Pitching tents in the open fields, they deserted their
houses, and awaited, in awful suspense, the issue of these terrifying prognostics.
On the morning of the 8th, a prodigious cloud of dense smoke darkened the atmo-
sphere, and was observed to be continually augmented by fresh columns arising
from bebind the low hills, along the southern base of which, the farms, constituting
the parish of Sida, are situated. A strong south wind prevented the cloud from
advancing over the farms; but the heath, or common, lying hetween them and the
volcano, was completely covered with ashes, pumice, and brimstone, The extreme
degree to which the earth in the vicinity of the volcano was heated, melted an im-
mehse quantity of ice, and caused a great overflow in all the rivers originating in
that quarter,
** Upon the 10th, the flames first became visible. Vast fire-spouts were seen
rushing up amid the volumes of smoke, and the torrent of lava that were thrown up,
flowing in a south-west direction, through the valley called Ulfarsdal, till it reached
the river Skafta, when a violent contention between the two opposite elements
ensued, attended with the escape of an amazing quantity of steam; but the fiery
current ultimately prevailed, and, forcing itself across the channel of the river,
completely dried it up in less than 24 hours ; so that, on the lth, the Skapta could
be crossed in the low country on foot, at those places where it was only possible
before to pass it inboats, The cause of its desiccation soon became apparent ; for
the lava, having collected in the channel, which lies between high rocks, and is in
many places from 400 to 600 feetin depth, and near 200 in breadth, not only filled
it up to the brink, but overflowed the adjacent fields to a considerable extent;
and, pursuing the course of the river with great velocity, the dreadful torrent of
red-hot melted matter approached and laid waste the farms on both sides. In the
mean time, the thunder, lightning, and subterraneous concussions were continued
with little or no intermission; and besides the crackling of the rocks and earth,
which the lava burned in its progress, the ears of the inhahitants were stunned by
the tremendous roar of the volcano, which resembled that of a large caldron in the
most violent state of ebullition, or the noise of a number of massy bellows, blow-
ing with full power into the same furnace.
“¢ The torrents that continued to be poured down proceeded slowly over the tract
of ancient lava to the south and south-west of Sk4l, which underwent a fresh fusion
and was heaved up to a considerable elevation. It also rushed into the subterra-
neous caverns, and during its progress under ground, it threw up the crust either to
the side, or to a great height in the air. In such places as it proceeded below a
thick indurated crust, where there was no vent for the steam, the surface was burst
in pieces, and thrown up with the utmost violence and noise to the height of near
180 feet. Bi
“On the 18th another dreadful ejection of liquid and red-hot lava proceeded
from the yoleano, which now entirely covered the rocks that had towered above
the reach of the former floods, during their progress through the channel of the
Skapta, and flowed down with amazing velocity and force over the masses that
were cooling, so that the one stream was literally heaped above the other, Masses
of flaming rock were seen swimming in the lava. The water that had been dam-
med up on both sides of its course was thrown into a violent state of ebullition, and
overflowing its boundaries, it did great damage to the grounds of Syinadal and
Hvammur, which farms had already been attacked by the edge of the lava, as also
to the underwood of Skaptardal on the east.
“© Continuing its progress the following day, the lava divided into two streams, one
of which flowed with the same velocity asthe day before due south, along the river
Melquisl into Medelland; while the other took an easterly direction over the parish
of Sida, burning the tract about Skdlarstapa, and running with inconceivable force
from thence to Sk4larfiall, by which it was prevented from spreading further north.
But, rising on the hill, it rolled up the soil before it, and approached within 120
feet of the church and houses of Ska), and overran the whole tract between that
place and Hollt. As Skél had now escaped the fury of two successive floods of
lava, sanguine hopes were entertained of its safety; but a great quantity of rain
having fallen on the 2lst, and swelled the water already dammed up in the valley,
the church, the parsonage, and out-houses, were completely overflowed; and the
whole tract was observed the following morning to be covered with water ina
state of violent ebullition.
“ While these awful devastations were going forward in the divisions of Skap-
tartunga, Medaliand, Landbrot, and Sida, theonly inconveniences felt by the inha-
bitants of Fliotshverfi were the destruction of vegetation by the showers of red-hot
stones and ashes which fell upon it, and the impregnation of the atmosphere and
water with mephitic substances. They had, indeed, twice been enveloped in almost
1818.] Scientific Intelligence. 309
total darkness, especially on the 28th of June, whenit wasso thick, thatit wasscarcely
possible at noon day to distinguish a sheet of white paper, held up at the window,
from the blackness of the wall on either side ; but they flattered themselves in the
hope that the lava would soon all be ejected, and at all events that it would con-
tinue to flow in the direction it had originally taken. However, on the 3d of
August, they were alarmed by a quantity of smoke, which they observed arising
out of the river Hverfisfliot ; and as the heat, which was also found to be in the
water, daily increased, till at last the river was totally dried up, they concluded
that the same destruction was about to be poured down upon them which had
overwhelmed the parishes to the west.
“* Nor were their apprehensions without foundation ; for the floods of lava having
entirely choked up the Skapta, and all the low channels to the west and north of
the volcano, it was forced to assume a new course, and running in a south-east
direction, between Mount Blengur and Hverfisfliot, it was discharged at length
into that river, which occasioned vast volumes of steam and smoke to arise from
that quarter, attended with dreadful noises and lightnings. The burning flood now
rap down the empty channel, and filling it tothe brink overflowed the low grounds
on both sides; and, by the evening of the 9th, it had not only reached the outlet
into the open and Jevel country, but in the course of a few hours had spread itself
to the distance of nearly six miles across the plain, and stopped up the road between
Fliotshverfi and Sida. The volcano still continuing to send forth fresh supplies of
lava, the red-hot flood spread itself wider and wider, and in its progress destroyed
the farms of Eystradal and Thverardal, the houses, meadows, and neighbouring
grounds of which are so completely covered, that the spot where they lay is no
longer visible, It also did considerable injury to the farms Selialand and Thvera,
and obliged their inhabitants, as well as the whole parish of KAlfafell, to flee for
their safety ; yet the above-mentioned were the only houses it burned. Though
this branch ceased to extend over the low country after the end of August, quanti-
ties of fresh lava continued still to be thrown up out of the volcano, and anew erup-
tion is said to have taken place so late as the mouth of February, 1784, during the
greater part of which year columns of smoke were observed to ascend from many
parts in the lava; and ithad not quite cooled for nearly two years after the erup-
tions were over. *
«© With respect to the dimensions of the lava, its utmest length from the volcano,
along the channel of the Skapta down to Hnausar, in Medalland, is about 50 miles,
and its greatest breadth in the low country between 12 and 15 miles; the Hverfis-
fliot branch may be about 40 miles in length, and seven at its utmost breadth. Its
height in the level country does not exceed 100 feet; but in some parts of the
Skapta channel it is not less than 600 feet high. +” :
ARTICLE X.
“SCIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS
CONNECTED WITH SCIENCE.
I. Lectures.
Mr. Cooper will commence his autumn course of lectures on
Practical Chemistry at his house, 89, Strand, on Tuesday, Oct.
13, at eight o’clock in the evening.
Dr. Stephenson will commence a course of lectures on Natural
History, on Wednesday, Oct. 14. The plan of the course is
intended to embrace a general outline of the science of Natural
History.
Mr. Mac Kenzie commences his next course of lectures on
* When Mr. Paulson visited this tract in the year 1794, he found a column of
smoke still arising from certain parts of the lava; and some of the rents were filled
with hot water,
+ Chief Justice Stephensen’s description of the Eruption of 1783, altered ac-
cording to Mr, Paulson’s MS,
310 Scientific Intelligence. {Ocr.
the Diseases and Operative Surgery of the Eye, Oct. 5, at nine
o’clock in the morning, on Mondays, Wednesdays, and Fridays,
at 16, Newman-street, Oxford-street.
II. On the Proteus anguinus.
This singular animal supposed to be a native only of the lake
of Sittich in Carniola, whence, in times of flood, it escaped into
the Cirknitzer see, and which was generally considered as the
larva of some unknown amphibious animal, has lately been the
su of an interesting letter from M. Rudolphi to Professor
inck.
According to M. Rudolphi it has recently been discovered in
the grotto of St. Madelaine, near Adelsberg, and in some other
small lakes, or pools, in the vicinity, in sufficient abundance to
have enabled him to procure 14 individuals.
The manners and habitudes of this animal hear a great resem-
blance to those of the salamanders. Although the eyes of the
proteus are very small, and covered by a skin of considerable
thickness, the animal appears very sensible to light, and its
motions, when thus exposed, are very brisk ; the veins, also,
beneath the transparent skin of the animal become at the same
time very turgid. Although capable of enduring so long conti-
nued an abstinence that it was generally supposed to take no
solid food, M. Rudolphi has found in the stomachs of a few of
them the remains of snails and of other small animals.
The, irritability and muscular power of the proteus are very
feeble. The globular particles of the blood are larger than in
any other known animal, and its lungs are a sac much resembling
the air bladder of fishes; which structure admitting only of a
very slow decarbonization of the blood, appears to account for
the very singular anomaly of the conjunct action of lungs and
gills in the same individual.
Cuvier, who some years ago dissected a specimen of the
roteus, demonstrated in it the presence of ovaries, thus render-
ing the opinion of its being a perfect animal and not a larva
extremely probable. This observation has been fully confirmed
by M. Rudolphi, who, in some individuals, has detected ovaries,
and in others testicles.
III, Nottce concerning certain Minerals lately discovered.
Several minerals have recently been discovered in the valley
of Fassa, in the Tyrol, and in different parts of Germany, whieh,
by Werner and his pupils, have been regarded as distinct species.
Specimens of these having been sent to M. Haiiy, were exa-
mined by him and by M. Cordier, the latter of whom has pub-
-lished a paper on the subject (Ann. des Mines for 1818, p. 1),
from which the following particulars are extracted. ;
Albin—This mineral, so called by Werner from its white
colour, occurs at Mariaberg, near Aussig, in Bohemia, imbedded
in clinkstone. It forms tubercular masses lining or filling cavi-
1818.] _ Scientific Intelligence. 31]
ties, and exhibiting superficially right prisms with square bases
terminated by truncated pyramids, the faces of which are placed
on the angles of the prism. The structure of the grains is gra-
nularly foliated with joints parallel to the bases. The colour
both of the grains and crystals is an opaque white. When
digested in hot nitric acid, it soon gelatinizes, and the same
effect takes place in cold acid after a few days. From these
characters it is manifest that this supposed new species is only
a variety of mesotype. :
Egeran.—This substance has been so named by Werner from
the place where it was discovered, Eger, in Bohemia. Its
gangue is a grey quartz covered in part with tremolite. It occurs
in the form of small, nearly opaque crystals, of a deep brown
colour. The form of the crystals is a right rectangular prism,
each longitudinal edge of which is replaced by a facette forming
an angle of 135° with the two adjacent sides. It possesses
natural joints parallel to the four principal sides and to the bases:
before the blow-pipe it melts into a black scoria. Hence it is
clear that this supposed new mineral is idocrase.
Gehlenite—So named by M. Fuchs in honour of the chemist
Gehlen. It was discovered in the valley of Fassa, and has the
form of small rectangular crystals, sometimes single, often imbri-
cated, disseminated in a gangue of lamellar calcareous spar. The
form of the crystals is a right prism with square bases, so low as
to be almost tabular. The colour is grey with a greenish or
yellowish tinge. The surface is dull, rough to the touch as if
corroded. The crystals are opaque, or nearly so, and somewhat
inferior in hardness to quartz. The fracture is uneven, passing
to splintery, with indications of joints parallel to the bases.
Specific gravity, 2°98. Before the blow-pipe it melts into a
brownish yellow transparent glass, which soon becomes opaque
and scoriform when acted on by the interior part of the flame. -
It is to be remarked that the crystals are often traversed by
minute veins of calcareous spar, and when reduced to impalpable
powder, the mineral dissolves in muriatic acid, and the solution
gelatinizes. The same property has been observed by M. Cor-
dier in the idocrase of Barreges, which occurs also in a calca-
reous base. Hence M. Cordier is induced to regard the
gehlenite as a variety of idocrase.
Helvin.—This substance, so wamed by Werner, was discovered
in the mine of Schwartzenberg, in Saxony. It occurs in a black-
ish green chlorite mixed with blende and fluor, in the form of
minute disseminated irregular octohedrons, of a pale yellowish
brown colour. Its fracture offers no indication of natural joints.
{t is softer than glass, and melts easily before the blow-pipe into
a blackish brown glass. The mineral acids when cold appear
to have no action on its powder.
_. Pelium—So named by Werner, was discovered at Bodemnais,
in Bavaria. It occurs imbedded in grey granite, in crystalline
312 Scientific Intelligence. [Ocr.
grains either solitary or aggregated. The form is that of a
regular hexahedral prism truncated on the edges and angles.
In form and other characters it perfectly resembles the dichroite
of Cape de Gatte, and of India.
Pyrgom.—By this name, Werner distinguishes the mineral
found in the valley of Fassa, and to which the name of fassaite
had already been given by the Italian mineralogists. In its crys-
tallization, its structure, and other essential characters, it
perfectly agrees with augite (pyroxene of Haiiy).
IV. On Sirium, a supposed New Metal.
A new metal is said to have been discovered by Prof. West,
or Vest, of Gratz, to which he gives the name of Sirium, a speci-
men of which has been sent over to this country. This, however,
we learn, upon being examined by Dr. Wollaston, proves to be
a compound, consisting essentially of a sulphuret of nickel and
cobalt, with a minute quantity of iron, and exhibiting also a trace
of arsenic,
In the Annales de Chimie et de Physique for May, there is
an account of this supposed metal from an anonymous corre-
spondent at Vienna, accompanied by some observations from the
editor ; a translation of which will, we trust, prove interesting to
our readers.
This metal is procured from the nickel mine of Schladminger,
where it is found united to a large quantity of arsenic and nickel,
with a little cobalt and iron. After having melted the ore in a
crucible with glass, it is pulverized and dissolved in nitric acid ;
the excess of acid is saturated, and the acetate of lead is then
added : an arseniate of lead is precipitated, but a portion of
arsenic still remains in solution. The excess of lead is separated
by sulphate of soda, the finid is filtered, and a little acid is
added, which is necessary to obtain the Sirium in a state of
purity. After having passed a current of sulphuretted hydrogen
through the solution, it is neutralized by carbonate of potash,
until a flocculent precipitate is formed, which is not re-dissolved :
if we then pass a second current of sulphuretted hydrogen
through the solution, the Sirium is precipituted in combination
with sulphur. It is an essential character of this metal not to
be precipitated from its solutions by sulphuretted hydrogen,
when they contain an excess of acid, but to be precipitated
when they are not in this state. The green fluid, from which
the Sirium has been precipitated, contains nickel, cobalt, and
iron.
If the dried sulphuret of Sirium be heated in a crucible lined with
charcoal, we obtain a black scorified mass with a metallic frac-
ture. This mass is pulverized, 1 of its weight of oxide of arsenic
is added to it, and it is heated for half an hour at a temperature
of about 60° W. The discoverer of this metal, M. Vest, procured,
in one oxporunenti a spongy regulus ; and in another, a compact
1818.] Scientific Intelligence. 3133
regulus, which consisted of the Sirium still containing sulphur,
arsenic, nickel, and iron, in consequence of the filter not having
been sufficiently well washed.
Remark of the Editor.—The above is the account of the dis-
covery which has been transmitted to us, and which, as we are
assured, has excited much attention among the Austrian philo-
sophers. The author of the letter may have omitted some
important particulars; for, as it now stands, nobody can give
credit to M. Vest’s Sirium, but must rather be impressed with
his want of experience. As he appears not to know that nickel
is not precipitated from its solutions by sulphuretted hydrogen,
when they are acid, and that it is partially precipitated when
they are neutral, we must beg him to repeat his experiments in
order to discover whether his Sirium be not merely very impure
nickel.
V. Notice on Picrotoxine, considered as a new Vegetable Alkali.
By M. Boullay.*
The term picrotoxine has been employed by M. Boullay to
express the acrid, narcotic principle, to which the cocculus
indicus, the fruit of the Menispermum cocculus, owes its
poisonous qualities.} This principle he conceives is analogous
to the morphium, which has been detected in opium, and which
appears to constitute the active ingredient in that drug ; and he
further supposes, that there are other vegetables which contain
substances that may all be regarded as belonging to the same
enus.
‘s A strong infusion of the seeds of the Menispermum cocculus,
to which ammonia had been added in excess, precipitated by
degrees the picrotoxine in the form of a white, granulated, and
crystalline powder. This precipitate, after being washed, is
partially dissolved by alcohol without colouring it, and is sepa-
rated from it by the spontaneous evaporation of the alcohol,
in the form of very beautiful silky needles.
A strong infusion of 100 parts of these seeds in alcohol, gently
evaporated to 4 of its bulk, had 10 parts of calcined and well-
washed magnesia added, and was boiled for a quarter of an hour.
The filtered fluid, which was powerfully acid before the addition
of the magnesia, was then found to be sensibly alkaline by its
action upon litmus paper and the tincture of rhubarb. A greyish
deposit was collected upon the filter, which, after being lixiviated
and treated with boiling alcohol, produced crystals of the same
nature with those obtained in the former experiment, except
that they were a little less white.
The picrotoxine which was obtained in these experiments had
only a weak action on vegetable colours ; but it readily dissolved
in acids, neutralizing them, and forming with them proper saline
compounds ; it is, therefore, especially from its property of
* Abstracted from Journ. Pharm. iv, 367. (Aug, 1818.)
+ Thomson’s Chemistry, iv. 55, (Fifth Edit.)
314 Scientific Intelligence. [Ocr.
saturating acids, like salifiable bases, that this bitter primciple
derives its claim to be considered as an alkali. The same
remark applies to morphium when it is in a perfectly pure state.
M. Boullay remarks that the bztter narcotic principle which he
first obtained pure and crystallized, and which appears to possess
the properties of an alkali of vegetable ongin, forms a new class
of bodies, of which it is probable we shall detect many species.
MM. Pelletier and Caventou have just discovered an alkali in
Nux vomica, and the bean of St. Ignatius, which probably must
be referred to this head.
The acid which appears to be naturally combined with the
picrotoxine, in the form of a super-salt, is supposed by the
author to be of a peculiar nature; it appears to differ from the
meconic acid; but this he proposes to make the subject of
further investigation hereafter.
VI. Extract from a Notice read to the Academy of Sciences,
Aug. 10, respecting the Discovery of a New Alkali.
This notice relates to the discovery made by MM. Pelletier
and Caventou, which is referred to in the last article. We
are informed, that in analyzing the Nux vomica and St. [gnatius’s
bean, they met with a new vegetable alkaline substance, which
is conceived to compose the active principle of these bodies.
{ts chemical properties are as follows.
It is slightly soluble in water, very soluble in alcohol, restores
the colour of turnsole after it has been reddened by an acid,
does not redden turmeric, combines with acids, which it satu-
rates, and forms with them crystallizable salts.
The discoverers have given this substance the name of vaw-
gueline, in honour of the celebrated chemist, who was their
preceptor, and who is said to have first discovered the alkaline
te nett of a vegetable substance which he procured from the
daphne alpina. The authors remark that the alkali from the
Nux vomica and from the Daphne, together with the picrotoxme
of M. Boullay, and morphium, will form the first genera ofa new
class of vegetable principles.
VII. On the Existence of Boracic Acid in Tourmaline and in
Axinite. By M. Vogel.
The existence of the boracic acid in tourmaline and axinite
was announced by M. Vogel tothe Royal Society of Munich, in
July last, as we learn from the number of the Journ. de Pharm.
for August, which we have just received.
After remarking upon the uncertainty which still attaches to
the composition of the tourmaline, M. Vogel gives an account of
the method which he adopted to procure the boracic acid in a
separate state: he declines detailing the complete analysis of
this mineral, because M. Gmelin of Tubingen is now engaged in
this investigation.
154-44 gr. (10 grammes) of black tourmaline, from the Upper
1818.] | Scientific Intelligence. 315
Palatinate, were kept at a red heat in a platinum crucible with
three times their weight of potash; the porous mass, which was
of a greenish brown colour, was well washed with boiling water,
so as to separate the soluble matter from the oxide of iron and
the earths which are insoluble in potash. The alkaline fluid when
filtered was slightly supersaturated by sulphuric acid, in order
to convert the earths into sulphates, and to decompose the
borate of potash which might have been formed at a red heat.
The fluid was evaporated to dryness, and the pulverulent resi-
duum treated with boiling alcohol, which has no action upon the
sulphate or the silex.
The alcoholic solution when filtered was observed to burn with
a green flame. Having been evaporated to dryness, and the
residuum heated in a platinum crucible to drive off the free sul-
phuric acid, a white substance remained which, when dissolved
in boiling water, deposited by cooling scales of a white pearly
appearance, which were vitrifiable by a red heat, and exhibited
all the properties of boracic acid.
M. Vogel also found boracic acid in a specimen of tour-
maline brought from Madagascar, which had been formerly
given him by M. De la Metherié.
If we wish to know, by a single operation, whether a mineral
contains boracic acid, it is only necessary to boil it for some
time in a crucible of platinum with twice its weight of concen-
trated sulphuric acid; the residuum, when nearly dried, is to be
washed with warm alcohol, which will burn with a green flame
if the substance contains boracic acid.
Experiments similar to those made with tourmaline have
enabled M. Vogel to detect the boracic acid in axinite from
Dauphiné.,
M. Vogel informs us, that in a late number of Gilbert’s Ann.
der Phys. there is a letter from Lampadius, in which it is said
that tourmaline contains boracic acid; but we have no particulars
given on the subject.
We are informed that M. Arfvedson has procured boracic acid
from tourmaline in combination with lithina.
a
The readers of the Annals are informed, that for reasons which.
qt ts unnecessary to obtrude upon the public, Mr. Aikin and
Dr. Bostock from this time cease to have any connexion with the
work. The last twelve numbers have been entirely edited by them ;
and, at dah whatever responsibility has been incurred during
this period falls upon them alone. The Editorship will now be
resumed exclusively by Dr. Thomson.
316 Colonel Beaufoy’s Astronomical, Magnetical, [Ocrt.
ARTICLE XJ.
Astronomical, Magnetical, and Meteorological Observations.
_ By Col. Beaufoy, F.R.S.
Bushey Heath, near Stanmore.
Latitude 51° 27/42” North. Longitude West in time 1/ 20°7’.
Astronomical Observations.
Aug. 8. Emersion of Jupiter’s firat 5 9 34’ 12/ Mean Time at Bushey.
SAfeNte =... oneness = 9 35 33 Mean Time at Greenwich.
20, Emersion of Jupiter’s third § 8 54 53 Mean Time at Bushey.
SALCUING! tose cieis caplet sea on 8 56 14 Mean Time at Greenwich.
31, Emersion of Jupiter’s first § 9 49 23 Mean Time at Bushey.
satellite...... bio-eele iele oi 5 9 50 44 Mean Time at Greenwich.
_ Magnetical Observations, 1818. — Variation West.
Morning Observ. Noon Observ, Evening Observ.
Month.
Hour. | Variation. Hour. | Variation. Hour, {| Variation.
Aug. 1} 8h 30! |j24° 34’ 29! 14 25/| 24° 44 99!) 7h 20’) 24° 37’ 15!
2| 8 30} 24 35 43 1] 25 | 24 47° 32 % 95 84) (Sh. ali
31 8 30] 24 35 18 1 35 | 24 48 25 Ti s20) SSUES. soe
4| 8 30] 24 34 56 1 25/24 48 10 T) 2588" 938" bo
5| 8 35 | 24 36 49 1 20| 24 45 12 7, 255/(24% 37. <320
6| 8 20] 24 34 52 1 25 | 24 46 06 120.) 298 3, AT.
7! 8 30) 24 34 05 1 25 | 24 44 51 7 20| 24 37 10
8} 8 25] 24 34 09| 1 25/24 44 44|! 7 20) 24 38 !7
9| 8 25) 24 34 34] 1 25|24 46 59) 7 25 | 24 37 54
10; 8 25) 24 338 56),— —|—_ — —/|— —|— —, =
11 8 40 | 24 39 58 1 25) 24 45 02 7 35 | 24 39 23
12; 8 30) 24 35 Al 1 20} 24 45 OL} — —J— — —
13) 8 35.124 36 382 1 25| 24 45 18 7. 25°) Sarat eo
14}...8 ):25)) 24, .38..55 1 25| 24 46 10 7 20 | 24 36 AT
15: 8,020 | 247733. 10 1 20); 24 47 ALJ} — —|— — —
16| 8 30] 24 34 10 1 35 | 24 AT 06 % 25 | OA °39 OF:
17 8 25 | 24 34 18 1 25 | 24 48 29 1 05 | 24 38 27
18| 8 25] 24 32 43 TO 1-94-46. 37 7 20} 24 39 06
19 8 30} 24 35 37 1 20} 24 4T 26 7 20| 24 37 Ov
201" 825 )'2t “32 ~e2 1 20 | 24 43 02 1 15 | 24 36 36
21 § 25 |24 34 OT 1 30| 24 51 30 7 20 | 24 38 02
22} 8 30 24 35 46 ) J 30 | 24 46 QI % 05 | 24 38 12
23{ 8 25 |24 34 18 D220.) Qa rat ote %. 05 | 24 37. 32
24; 8 25/24 35 19] 1 25)24 45 34] 7 05 | 24 38 05
25} 8 30|24 34 42 1 25 | 24 45 59 7 05 | 24 31 36
26) 8 25)24 31 35 1 30| 24 42 41 7 05 | 24 37 20
QT 8 25]24 35 02 1 20) 24 46 32};— —|j— — —
28| 8 25 | 24 32 45 1 15 | 24 40.39 7 05 | 24 36 46
29; 8 30) 24 42 10 1 25 |24 46 43 7.10) 24 37 30
30} S 25] 24 34 43 1 30| 24 44 52 7 05 | 24 38 16
31} 8 30| 24 34 18 1.25 | 24 48 13 7 05 |24 40 56
Mean for ‘ 8 28| 24 34 40] 1 95194 45 58] 7 16/94 37 50
Month,
In taking the monthly mean of the observations, those on the
morning of the 29th and noon of the 21st are rejected, being so
much in excess, for which there was no apparent cause.
Month.
1818.]
Time,
Even...
Noon...
Even....
Morn,...
Noon....
Even .
Morn...
Noon,,..
Even....
f Even....
Morn....
Noon,...
Even....
Morn.,...
Noon....
.C|Even....
Morn....
Noon....
Even ....
Morn,...
Noon....
Even....
Even....
Noon....
Even....
Noon,...
Even....
and Meteorological Observations.
Meteorological Observations.
Inches,
.| 29°548
-| 29°578
.| 29°625
-| 29°700
.| 29-713 °
29-690
-| 29°690
-| 29°654
-| 29°652
-| 29°670
-| 29°670
29-685
29-658
29°657
-| 29°640
29°630
29°635
29-650
-| 29-650
-| 29°650
29°647
29-654
29-654
29-618
29°563
29-540
29-500
29:500
29°753
29°T47
29-740
-.-| 29°666
29-668
-| 29-690
«-| 29-710
29-700
-| 29-685
29°680
-| 29°665
29-647
-| 29-645
...| 29°668
--.| 29°665
.| 29°645
..| 29°623
.| 29°600:
-| 29°594
-| 29°552
29°523
29°525
62°
66
50°
42
WwW a N
WNW
ENE
ENE
ENE
ENE
E
NE by N
NNE
NNE
NNE
NNE
NW by N
Var.
Calm
Calm
NW
NNW
NE
Var,
NE
Barom. | Ther.| Hyg. | Wind. poi Weather, Six’s.
Feet.
2°793
9-810
9:238
8-044
11°393
10°447
14:561
11-859
8-332
4-979
3°561
4011
317
Cloudy 55S
Cloudy 67
Cloudy
Very fine os
Very fine} 71$
Very fine Re
Very fine
Cloudy
Fine
Very fine bss
Very fine| 81}
Fine
Clear oe
Clear
Clear
Very fine be os
Cloudy
Cloudy
Very fine -
Very fine} 71
Fine
Fine te
Fine
Fine
Rain fa se
Fine
Fine
peda! ts ss
Very! fine bs =
Cloudy Tg
Fine
Cloudy ‘ sl
Fine iL
Very fine ; <-
Fine 13h
Fine 1
Very fine ‘ 5
Cloudy 66
Cloudy
Cloudy ‘ 54
Cloudy 65
Cloudy : -
Fine 695
Very fine 53
Fine ‘
Fine 12
Cloud
Cleie’ ‘ Lg
Fine 12
Fine
TL
318
Month. | Time.
Aug. Inches,
Morn,..,.}. 29°505
192 {Noon..,.} 29°510
Even....| 29°563
Morn... .} 29°614
#02 |Noon,...| 29°615
Even....| 29-625
Morn... || 29°625
212 |Noon,...| 29°625
Even ....| 29.620
Morn....| 29°610
g24 |Noon....| 29-640
Even ....| 29°672
Morn,...} 29°T70
23 Noon,...| 29°770
Even ,..} 29°767
Morn,...| 29°754
24 |Noon,.. .| 29°728
Even ....| 29°687
Morn,...} 29°658
25 Noon,...} 29°665
Even ,...| 29°665
Morn,...| 29°584
26 Noon,...} 29°546
Even....| 29°513
Morn,...| 29°420
an} Noon....| 29°341
Even... .} 29°290
Morn... .} 29°245
20} Noon,...| 29°255
Even....} 29°393
Morn.,...} 29.527
29 Noon,...| 29°538
Even ....| 29°538
Morn....} 29°457
30 Noon....| 29°457
Even ..,.} 29°515
Morn....| 29°570
31 Noon,...} 29°515
Even ....| 29°453
Col. Beaufoy’s Meteorological Observations.
Meteorological Observations continued.
Barom. } Ther. | Hyg.
56°
63
, 5T
56
62
60
64
64
59
» 55
61
56
54
66
61
59
64
59
59
66
61
58
64
62
58
61
63
68
62
61
13
, 66
62
710
61
58
68
62
440
33
34
43
33
32
43
30
35
35
28
30
A2
28
35
3T
30
33
AA
30
30
Wind,
NNE
NNE
NE
NW by W
NW by W
WNW
NNW
Var.
Var.
NNW
NNW
NNE
N
Nby E
NW by W
WwW
W by N
WSW
WNW
Ww
Calm
Ww
WSW
WNW
W byS
SSW
WobyS
Ww
W by N
W by N
Ww
WwW
W
Wsw
Ww
WNW
Sby W
SSE
S
Velocity.
Feet.
9°332
8°753
4204
11-196
93-099
-10°564
9-204
6°765
[Ocr,
Weather.| Six’s.
Fine 50°
Cloudy 64
Cloudy
Cloudy ; =
Cloudy 643
Fine 52
Cloudy
Cloudy 66
Rain
Cloudy ‘ 48
Cloudy | 63
Fine
ine t at
Fine 68
Cloudy |
Cloudy ‘ 56
Cloudy 653
Fine 54
Cloudy ¢
Fine 68
Cloudy
Sm. rain : 528
Showery | 67
Cloud
Cloudy ; 55
Showery | 62
Showery
Fine ; 58
Cloudy 69
Cloudy
Fine t 51
Fine 14
Fine
Cloudy ; ST
Fine 12
Cloudy
Very fine ‘ an
Very fine} 70%
Rain, by the- pluviameter, between noon on the Ist of Aug.
and noon on the Ist of Sept. 0°491 inches. The quantity that
fell on the roof of my observatory, during the same period,
was 0°457 inches. Evaporation, between noon the Ist of Aug.
aut noon the 1st of Sept. 7-03 inches.
1818.] Mr. Howard’s Meteorological Table. 319
ARTICLE XII.
METEOROLOGICAL TABLE.
BAROMETER, TRERMOMETER,
1818, |Wind. | Max.| Min, | Med. |Max.}Min.| Med,
$th Mon.
Aug. 23} N_ /30'20/30°15130°175| 66 | 58 | 62°0 50
245 W/1/30°15|30°07|30°110) 71 | 56 | 63:5 42
25IN W/130:07|29'95|30-010| 72 | 50 | 61-0 45
26\N W1/29:95|29:75|29'850) 75 | 55 | 65:0 A7
27| W_ |29°75|29'60|29°675' 68 | 60 | 64:0 43
28IN W{29-94/29-65|29°793| 73 | 53 | 63-0 52
29| W_ |29-94)29°86)29'900) 80 | 58 | 69-0 48
30|. W_ |30-00/29-86/29-930| 76 | 40 | 58:0 52
31} E |20°00|29'49)29°745| 75 | 55 | 650 50
Oth Mon. .
Sept. 1/8 W/29°70)29*49/29°595| 74 | 49 | 61°5 50
2S W/30-07/29°70|29°885| 71 | 50 | 60%5 59
S W{30:05!29°92/29-985! 71 | 61 | 66-0 Ag
S_— |29:99|29-96|29'975| 75 | 63 | 69-0
W |29-96|29°70/29'830! 68 | 55 | 61°5 66
W /29°85|29'70/29'775] 69 | 55 | 62:0 65
N_ W/29°92/29°85|29'885| 64 | 45 | 54:5 46
Var. |29'90|29°60/29:750] 65 | 40 | 59°5 60
N W(29'68/29°59)/29'635| 63 | 43 | 53:0 65
10|\N _E/29°85/29-68/29:765| 61 | 39 | 50-0
11/N W/{30°00/29-85|29-925| 60 | 42 | 51-0
12,/N_W/30°20)30:00/30°100} 66 | 48 | 57-0
13} N_ |30°30/30°20|30°250] 68 | 41 | 545
14S W/{30:25/29°75|30:000} 67 | 58 | 69:5
15'S W\29-75|29-60129-675| 59 | 43 | 51-0 50
16\N W(30'10/29°60)29°'850| 56 39 | 47°5 60
17|_N_|30-20)30:05/30°125| 57 | 41 | 49:0 57
18N W/30:05/29°85|29-950| 63 | 51 | 57°0 72
19} S |29°85/29°58|29°'715] 67 | 50 | 58°5
20S E/29'58|29-38/29-480| 61 | 44 | 59°5 60
21'S E/29°63/29°32/29'475| 69 | 49 59:0 70
Hyer. at
9 a.m. |Rain,
CO ONO, Oh Od
ES | ES
30°30/29°32|29°860| 80 | 39 | 58-68! 54
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 result is included in the next following observation,
REMARKS,
Eighth Month.—23, Morning very clear : mid-day Cumulus beneath large Cirri:
P-™. inosculation, followed by a shower to the NW, which sent us a turfy odour
withthe wind, 24. Cirrostratus, followed by Cumulostratus, at times heavy ; the
wind veered to SW, p.m, 25. Large Cirri, directed from SW to NE, 26. Cumu-
lostratus and Cumulus crossed by Cirrostratus, 21. The hygrometer advanced to
67°: gentle rain, a,m.: cloudy, p.m, 28. Cumulus and Cumulostratus : a little
rain, evening. 29. Cirrocumulus, beautifully coloured at sun-set, in lake shaded
with violet. 30, Some very light rain, a.m; fair, with fresh breeze after it,
31. Large plumose Cirri,
320 Mr. Howard’s Meteorological Journal. [Ocr. 1818.
Ninth Month.—1. Lowest temperature on the ground 44°, This morning from
two to three it thundered and lightened much to the SE: thunder clouds prevailed,
a,m.: wind SE, and a little rain: a slight shower again at night, and much dew
after it: the hygrometer advanced to 80°. 2. After large Cirri, Cumulostratus,
which inosculated about sun-set with a scanty Cirrocumulus. 3. A mixed sky, with
a slight driving shower at evening: cloudy night, 4, A sweeping rain, early:
hygrometer, 80° at six, a.m. : much hollow southerly wind: Cérrocumulus, followed
by ill-defined Cirrus with Cumulus ; and about five, p.m. a Nimbus, shaped like a
low, circular hay-rick, with a capped Cumulus by its side, on the NE horizon.
5. Much rain, for the most part small and thick, 6. Wet, cloudy morning: very
turbid sky: hygrometer at 80°: calm air: tn the evening, inosculation of Cumulus
with Cirrocumulus; after which frequent lightning between nine and ten, p.m.
T. Morning gray, with Cirrocumulus : sun-shine followed, with inosculation of Cu-
mulus and Cirrostratus. 8. Large Cirri, with fleecy Cumuli: the latter attached
themselves in their passage to the smoke of the city, and appeared to disperse
downwards intoit. Thunder clouds followed this appearance, and a smart storm
passed in the S, from Wto E, about five, p.m.: the crown of the nearest Nimbus
reached our zenith, and we had a few drops; while it rained hard, with a bow in
the cloud, within two miles of us. 9. Heavy Cumulostratus: and showers, p. m.
10. Fine breeze, with Cumulus and Cirrus; the latter survived the sun-set, and was
kindled with dame colour passing to red: calm at night, with hygrometer 45°,
¥1, 12,13. Chiefly Cumulus, and Cumulostratus by inosculation: some fine group-
ing of the clouds at intervals: large Cirri at the conclusion. 14, A large meteor
seen passing northward: windy night. 15. Cloudy, windy: hygrometer, 75°:
wet, p.m. 16. Much dew: a rapid propagation of Cirrus from the S, followed
by Cumulostratus and showers: during a heavy shower about nine, p.m. it thun-
dered in the N W: the barometer stationary great part of these two days at 29°60
inches. 17—20. Windy at intervals, with €irrostratus, turbidness, and driving
rains, 21. Much wind, with showers: the sky turbid, and streaked with Cirro-
stratus, in a direction fram SE towards NW : calm night.
RESULTS.
Wind for the most part Westerly, and moderate.
Barometer : Greatest height ......-....+--+++--- 30°30 inches.
east. oc. aces aasiee Sige Se sineisspuee nee
Mean of the period. ........ +++. 29°860
Fhermometer: Greatest height..........+++e+-++++- 80°
Least, ..... 2.00 coecccecccess Sencar 39
Mean of the period...........+-+.. 58°68
Mean of the Hygrometer.......2.2 seeeeeee poles a tak ee
Evaporation.........2...05-+- odo ccccesecessovcece 2°33 inches.
Raings.«---% be Cabs be tanpe ee pce oe dela We ose Masts wet J LAG IDEMEgs
The rains of this period, though absorbed by the parched ground as by asponge,
haye completely restored vegetation in our meadows, which have resumed, in the
space of a few days, a yerdure equal to that of spring. Neither the natural nor
the artificial indications of this change of weather were very striking: the most
considerable being, probably, the sudden increase of temperature in the nights pre-
yious to the more considerable falls of rain.
Torrennam, Ninth Month, 22, 1818. L. HOWARD.
Large Meteor.—On the \4th of the ninth month ( Sept.) about half-past 10, p. m.
a meteor was observed, ina direction nearly due north from Tottenham, which
must have been a yery conspicuous object to the inhabitants of more northern
countries. When first observed, it was but moderately elevated above the horizon
ov which it appeared to descend slowly, continuing in sight for some minutes. My
informant judged its apparent diameter to be at first equal to that of the moon
when at her greater elevation : it hada diverging train, which was compared toa
brush: the colour white, changing to red as the body descended and decreased in
diameter; at which time a second observer reports that it simply emitted sparks.
The course of this meteor was probably directly northward from the eye, which
may account for ifs apparently slow motion. Further observations from those who
may have seen it more to the north will be acceptable, I am not enabled to give
the particulars with greater precision than as above.
ANNALS
OF
PHILOSOPHY.
NOVEMBER, 1818.
—____.-______
ARTICLE I.
Biographical Account of Sir Torbern Bergman, Professor of
Chemistry in Upsala. By Thomas Thomson, M.D. F R.S.
I AM induced to draw up the following account of Bergman
because I consider the events of his life, spent as it was in the
tranquillity of the University of Upsala, as furnishing an admir-
able lesson to the young chemist of the result of unremitting
industry when united with a good education and excellent abili-
ties, and its ultimate tendency to overcome all the obstacles
thrown in the way of its possessor by the jealous rivalship of
contemporaries, or the malignant obstructions of those who
already occupy the stations to which a poor man of genius natu-
rally looks forward. My knowledge of the biographical facts is
derived partly from the oration of Hjelm, delivered in the Royal
Academy of Sciences at Stockholm, on May 3, 1786; and
partly from the eloge of Bergman drawn up by Condorcet, and
printed in the Memoirs of the French Academy.
Torbern Olof Bergman was born on March 9, 1735, at Cathe-
rinberg, in West Gothland. His father, Barthold Bergman,
was a revenue officer in the district of Wadsbo, and the province
of Skaraborg. His mother, Sarah Hage, was a merchant’s
daughter in Gothenburg, who had been previously married to
another revenue officer. Torbern Bergman was the eldest child
of this second marriage ; and his mother bore afterwards two
other children, a son and a daughter.
The first part of Bergman’s education was conducted at home.
In the harvest of 1740 he went to the school of Skara, There
he remained for six years, studying with great zeal and much
Vou, XII. N° VY.
322 Biographical Account of [Nov.
improvement. Besides Latin, logic, and natural philosophy, he
acquired a knowledge of the plants growing wild in the neigh-
bourhood of Skara, and made some progress in the Greek and
Hebrew languages. In the autumn of 1752 he was sent from
this school to the University of Upsala, where he was admitted
with some eclat as a student of the Westgothland nation. We
are informed by Condorcet that Bergman was destined by his
father for the church, or the law, as professions which opened
to his views the most desirable situations for a literary man
which Sweden possessed: that he went to the University of
Upsala with this intention, and commenced his studies under
the inspection of a friend ; but that he very soon testified a dis-
like to both the professions proposed for his choice, while he
manifested a violent passion for mathematics and physics. His
friend remonstrated, poimted out the absurdity of his choice,
told him that law and divinity were the roads to profit and
yeaa while mathematics and physics had nothing to
estow upon their votaries but reputation. Our young philoso-
pher listened to these remonstrances in silence, but still perse-
vered in his favourite pursuits. His friend deprived him of his
books, restricted his studies, and left him only to choose
between law and divinity.* This restraint almost proved fatal.
Bergman’s health declined. It was found necessary for him to
leave the university and return home. His relations, finding it
in vain to struggle with his inclinations, at last indulged them,
and left him at liberty to pursue those studies of which he was
30 distractedly fond.
While a student at Upsala, Bergman devoted himself with
the most unremitted attention to the study of mathematics,
physics, and philosophy. He was in the habit of getting up at
four in the morning, and of going to bed at eleven. The books
which he studied in the first place were Wolfe’s Logic, Walle-
rius’s System, Euclid’s Elements, Keil’s Physics and Astronomy.
These last two works were then reckoned the best introduction
to mechanical philosophy.
At that time, Linneus, after having surmounted obstacles
sufficient to have crushed a man of ordinary energy, was in the
height of his glory, and was revered every where as the
patriarch of natural history. He had infused the enthusiasm
which actuated his own breast into the minds of his pupils, and
at Upsala every student was a natural historian. Bergman, in
particular, attached himself to Linneus, and bestowed much
pains on botany and entomology. This last branch of natural
history indeed is deeply indebted to him. He first displayed in
it those powers of arrangement which constitute the charm of
his works, and that penetration which produced afterwards such
important fruits.
* This friend was Jonas Vietorin, his eousin, at that time Magister Docens iz
the University of Upsala.
1818.] Sir Torbern Bergman. 323
He examined the different species of hirudines, or leeches,
which are natives of Sweden. While engaged in this examina-
tion, he made a discovery which I shail endeavour to explain.
The females of the genus of insects, called by Linneus coccus,
adhere to the plants on which they feed so immoveably that
they have the appearance of gadls rather than animals. Linneus,
in the Fauna Suecica, No. 2080, described an animalcule which
he was disposed to consider as a female coccus ; but as no one
had seen it, except adhering to aqueous plants, the Swedish
Pliny was unwilling to decide whether it was really a coccus or
the ovum of some aquatic animalcule. Bergman instituted a
set of observations on this substance, and soon ascertained it to
be the ovum of the hirudo octoculata. Linneus was at first
unwilling to credit the truth of this discovery ; but when Berg-
man had convinced him of the accuracy of his observations by
ocular demonstration, Linneus sent the account of them, as
drawn up by his pupil, to the Stockholm Academy, with a very
flattering panegyric. Vidi et obstuput.
ai iaan speedily distinguished himself by numerous papers
on different branches of natural philosophy. He passed rapidly
through all the gradations of rank usually conferred on students
at Upsala, and in 1761 was appointed Magister Docens in
physics. During the six years which he filled this situation he
still further distinguished himself by a great number of ingenious
apers ; for example, on the aurora borealis, on the rambow, on
the twilight, &c.
In the year 1767, Johann Gottschalk Wallerius, who had
long been Professor of Chemistry at Upsala, and possessed a
very high reputation, resigned his chair. Bergman was at that
time by far the most distinguished young man at the University
of Upsala, and had not neglected his chemical more than his
mathematical studies. His dissertation on the manufacture of
alum, published on April 1, 1767, and his treatise on physical
geography, which had made its appearance a year earlier, afford
specimens of a minute knowledge both of chemistry and mine-
ralogy, such as could scarcely have been looked for from a
person who had not hitherto devoted himself exclusively to
chemical pursuits. He accordingly offered himself a candidate
for the vacant chair; and his dissertation on the manufacture of
alum seems to have been composed chiefly to show his acquaint- ~
ance with the science which he aspired to teach.
But Wallerius had other plans. There was a relation of his
own whom he wished to succeed him; and such was the in-
fluence of that celebrated Professor, that there was every proba-
bility of his accomplishing his objeét. It is asserted by
Condorcet, that he attacked Bergman’s dissertation on the
manufacture of alum in a style of acrimony which did him but
little credit.
Gustavus IV. afterwards so distinguished when King of
x 2
.
324 Biographical Account of [Nov.
Sweden, was at that time Crown Prince and Chancellor of the
University of Upsala. The character and abilities of this
extraordinary man are well known. He entered with his usual
zeal into the dispute respecting the chemical chair, and consulted
Von Swab and Tilas upon the merits of the candidates. Neither
of these eminent men was personally acquainted with Bergman ;
but they were not ignorant of his wntings nor of the high
character which he bore at Upsala for industry and talents.
Von Swab’s opinion of Bergman’s chemical skill was founded
upon the dissertation on the manufacture of alum, while Tilas
came to a similar conclusion from the second part of the physical
geography which Bergman had written. Fortunately for
chemistry and for the reputation of Sweden, both of them
strenuously recommended Bergman as the candidate who ought
to get the professorship. Gustavus, im consequence, took the
part of our young philosopher; and he was so keen on the sub-
ject, that he supported his cause in person before the senate.
allertus and his party were of course baffled, and Bergman
got the chair.
His previous education and habits fitted him peculiarly for the
cultivation of that science to which he was to dedicate the
remainder of his life. At that time the intimate connexion
between physics and chemistry, which is now so close that the
exact boundaries of the two sciences cannot be defined, was
not quite so visible. The mode of reasoning was not. exactly
similar to that which was followed by those who cultivated
mechanical philosophy; certain occult causes and unknown
bodies were admitted without hesitation, and were supposed to
play a very conspicuous part among chemical phenomena. It is
sufficiently obvious that a man familiarly acquainted with the
rinciples of mathematics, accustomed to mathematical reason-
ing, capable of applying it to the different branches of mecha-
nical philosophy, skilled in the phenomena and laws of
electricity, optics, hydrostatics, and pneumatics, and possessed
of those general views which are the natural result of a complete
education—it is sufficiently obvious that such a man must
possess prodigious advantages in studying chemistry over the
uninformed and contracted mind of the mere chemist. Even at
present when the science of chemistry has made considerable
progress, when its principles are in some measure established,
and the mode of investigating its phenomena ascertained, it is
easy, at a single glance, to perceive the superiority of those
who have imbued the principles of mathematics and physics
over those who have been so unlucky as not to have received a
sufficiently liberal education. When Bergman began his che-
mical career, these advantages must have been of still greater .
importance than they are at present, because the principles of
the science were still to be investigated, and many prejudices
and false opinions, originating from ignorance and contracted
1818. Sir Torbern Bergman. 325
views, still retained their full force. Accordingly, it is the
extent of the views, the soundness of the reasoning, and the
excellence of the arrangement, which constitute the merit of
Bergman’s writings. His powers of invention do not seem to
have been great; he scarcely ever attempted to investigate
unknown substances, nor do we owe to him the discovery of a
single new simple body, or gas; while Scheele, though his
situation was apparently much less favourable for such investi-
gations, brought to light a vast number of new bodies, and made
a greater addition to chemical substances than any chemist that
either preceded or followed him. But Bergman appears to have
been more fully aware of the extent of his science than any of
his contemporaries. He had experimented on all the chemical
bodies that were known in his time. His dissertations are more
complete than any contemporary ones. He first laid down the
rules for the application of chemistry to minerals and waters.
His essay on elective attractions, though much of it was theo-
retical, displays the extent of his views in a very conspicuous
manner. It must have contributed very materially to the future
progress of the science by pointing out to chemists the facts
already known, and the vast number of blanks which required
to be filled up before chemistry could be considered as approach-
ing to perfection. Though his views respecting affinity were
not all sound, and though he reduced its laws to a degree of
simplicity which the phenomena do not warrant, yet this does
not appear to have been injurious to the advancement of know-
ledge, because new facts were to be acquired only by experi-
ment; and this was the mode of investigation universally
adopted. Berthollet, who pointed out the weak parts of the
Bergmanian views respecting affinity, has himself advanced a
new theory, which he ie supported with infinite ingenuity and
sagacity. No chemist ever possessed a greater stock of genius ;
and he draws upon it in his endeavours to support this theory in
the most lavish manner. But Berthollet’s theory, notwithstand-
ing the abilities of its inventor and the admirable way in which
he has contrived to support it and to palliate its defects, is still
less conformable to the phenomena than Bergman’s ; forif car-
ried to its full extent, it would destroy the existence of definite
compounds altogether; that is, it would destroy the very
existence of the science which it was brought forward to
improve; for if there were no definite compounds, there could
be no such science as chemistry at all. The fact seems to be,
that the investigation of the ultimate laws of affinity (af the
expression be allowable) is beyond our reach, at least in the
present state of the science. If we ever are to arrive at any
precise facts respecting these laws, it must be by an indirect
‘road; and, indeed, the atomic theory seems likely to throw
some light on the subject. But that theory must be much
further advanced than at present, before we can have it in our
326 Biographical Account of [Nov,
power to draw any important consequences from it respecting
the laws of affinity.
Bergman filled the chemical chair at Upsala for 17 years, and
during that period his numerous publications entirely altered
the appearance of the science. He introduced an order, a
perspicuity, an exactness, which were unknown before, and
which were certainly one of the great causes of the subsequent
rapid progress of chemistry. Their influence was universally
felt; and as long as Bergman lived, he was universally looked
up to as one of the patriarchs of the science.
To satisfy our readers of the high reputation which Bergman
acquired, we may mention the attempt of the great Frederick
of Prussia, in 1776, to prevail upon him to become a member of
the Prussian Academy of Sciences, and to settle at Berlin.
Bergman took some time to consider the offer of his Prussian
Majesty, which was highly honourable, and advantageous even
in a pecuniary point of view; but the King of Sweden, who was
justly proud of his illustrious subject, would not permit him to
transfer his allegiance, announcing, that he would consider his
expatriating himself as a personal offence to his Majesty. As
some compensation for this sacrifice, Bergman received the
honour of knighthood, and a pension of 150 mx dollars was
annually paid him out of the Royal treasury.
Nor is it a less striking proof of the estimation in which he
was held in foreign countries that the Royal Academy of
Sciences of Paris, on the death of Sir John Pringle, elected him
one of the eight foreign associates to which their number was
restricted. He had been a Fellow of the Royal Society from the
year 1764. This honour is never conferred except upon the
most distinguished foreigners. Though as the number of such
Fellows is not limited, as was the case with the French Academy,
the same kind of difficulty does not present itself to prevent the
conferring of such an honour upon such individuals as are con-
sidered to be deserving of it.
But it was not his’ publications alone which constituted his
merit. His lectures were no less valuable ; and the pupils whom
he educated contributed,-in no small degree, to spread his repu-
tation. Gahn, Hjelm, Gadolin, the Elhuyarts, and others, who
afterwards acquired celebrity, were educated by him. His first
care after obtaiming the ¢hair was to collect all the different
chemical substances and their products, and to form them into
a cabinet. Another cabinet contained the minerals of Sweden,
arranged according to the places where they onigmated; and a
- third consisted of models of the different instruments employed
in chemistry and in chemical manufactures. These were de-
signed for the instruction of his pupils, whom he encouraged
and inspired with that confidence and enthusiasm which is
requisite for the successful prosecution of practical chemistry.
His treatment of Scheele deserves to be mentioned with parti
1818.] Sir Torbern Bergman. 327
cular approbation. This extraordinary man was a journeyman
apothecary, at Upsala, when Bergman got the chemical chair
in that University. Ihave been informed by Assessor Gahn, at
Fahlun, who was at Upsala at the time, and who enjoyed the
friendship and confidence of both of these great men, that
Scheele’s first attempt to get acquainted with Bergman consisted
in sending him a paper describing the method of procuring pure
tartaric acid. This paper was written in German ; and being
upon a subject which many other persons had before treated
unsuccessfully, and coming from a person entirely unknown, and
whose appearance did not promise much, Bergman neglected to
read it, and of course took no notice whatever of the communi-
cation. Scheele was naturally hurt at this negligence, which he
so little deserved. He sent the communication to Retzius, who
made it known by publishing the process in the Memoirs of the
Stockholm Academy. This unfortunate commencement preju-
diced Scheele against Bergman, and made him unwilling to
renew any correspondence with him. But when the ice was
once broken, he became sensible of Bergman’s worth, and gra-
dually became his intimate friend. The Professor gave him the
free use of his laboratory, which. must have been of infinite
importance to Scheele while he remained at Upsala. He
adopted his opinions, supported them with zeal, and took upon
himself the charge of publishing his papers. It is even said by
some, though I do not know whether the allegation be well
founded, that he procured him a small pension from the Stock-
holm Academy to contribute towards the expense of his experi-
ments.
Bergman is by no means remarkable for the precision of his
experiments ; indeed, the time for accurate chemical experi-
ments, as far as quantities are concerned, had not yet arrived.
Bergman and his contemporaries were occupied with the inven-
tion of new methods of analysis. The numerical data could not
be expected to be accurate. It is only within these few years,
since the discovery of the atomic theory, that accurate chemical
experiments have become possible ; and even at present, we
have no accurate means of distinguishing between a true chemi-
cal compound and a mechanical mixture. Hence the mistakes ©
still so conspicuous in the numerical analyses published by the
most accurate chemists of the present day. There is likewise
another thing to be taken into consideration before we condemn
Bergman for want of accuracy. He wrote so much in so short
a time, and all his papers are details of so numerous a train of
experiments, that it does not seem possible, making every
allowance for his industry and dexterity, for him to have per-
formed the whole of his experiments with his own hands. He
must have trusted a good deal to those who had the care of his
laboratory. Who these were, we have no means of knowing,
though it is obvious that upon their skill and attention, a great
328 Biographical Account of [Nov.
deal of the value of his papers would depend. John Afzelius,
his nephew, who afterwards succeeded him, was for some years
his assistant, and must of course have performed most of his
experiments during that time. Afzelius was considered as an
accurate experimentalist, his reputation was high, and he
succeeded his uncle without opposition. Eut 1 am not ac-
quainted with any thing which he has published since Berg-
man’s death, except a single paper on the analysis of sulphate
of barytes.
Bergman’s health for some years previous to his death had
become delicate. He was afflicted with the hemorrhoids, and
threatened with an hemoptysis. His immediate death seems to
have been occasioned by violent hemorrhoidal discharge which
brought on general convulsions, accompanied with the total loss
of understanding. This continued for ten days, at the end of
which he sunk altogether. He died on July 8, 1784, at the
mineral wells of Medevi on the Lake Wetter, to which he had
repaired in consequence of the badness of his health.
His death was followed by the most unfeigned sorrow, not
only of those who were at that time at Medevi, but of the
whole inhabitants of Sweden. He was buried at Westra
Nykyrke, not far from Medevi; and his funeral was attended
by almost the whole population of Medevi, and by a prodigious
concourse of people from every part of Sweden. Never was a
man of science more respected, nor a professor more lamented,
than Bergman. Scheele followed his fnend in two years; and
Sweden, from bemg one of the first chemical countries in
Europe, sunk at once, as far as that science is concerned, into
comparative insignificance and absolute torpor. At present,
indeed, in consequence of the unequalled activity, and zeal, and
skill of Professor Berzelius, that kingdom has resumed her rank
among chemical nations ; but a listlessness of nearly 20 years
elapsed before this activity began.
Bergman’s papers amount altogether to 106. They were
published between the year 1755, in which his maugural disser-
tation “ De Crepusculis ’ appeared, and the year 1784; for his
little paper entitled ‘ Mineral Observations ” was published
only a few weeks before his death. The greater number of
them were collected in six octavo volumes entitled ‘‘ Torberni
Bergman Opuscula Physica et Chemica.” The first three
volumes of this collection were published by Bergman himself n
the years 1779, 1780, and 1783. The fourth volume was
published at Leipsic in 1787, and was edited by Dr. Emest
Benjamin Gottl. Hebenstréit. The fifth volume was published
by the same editor in 1788; and the sixth and last volume,
which.contains some of the most early papers of our author, did
not make its appearance till the year 1790. In the observations
which I mean to make on these productions of Bergman, I shall
pass over his essays on natural history and physics, and confine
1818.] Sir Torbern Bergman. 329
myself to his chemical papers, on which his reputation in a great
measure depends. These, if we omit the Physical Geography,
the Notes on Scheffer, the Sciagraphia, and the History of
Chemistry, amount to about 48. It will be most satisfactory,
perhaps, to take them in the order in which they occur in the
Opuscula, as this was the order which Bergman himself gave
them. The first two volumes of the Opuscula, and part of the
third, were translated into English by Dr. Edmund Cullen and
Dr. Beddoes, and the fourth volume by Mr. Heron. I am sorry
to observe that Mr. Heron’s translation is far from accurate.
He often mistakes the meaning of his author, and does not
appear to have been sufficiently acquainted with the science of
chemistry to understand Bergman’s Latin; which, though suffi-
ciently perspicuous to one acquainted with the subject discussed,
is not, perhaps, always classical. ,
1. He prefaces his Opuscula with.a short dissertation on the
Investigation of Truth, in which he gives us the rules which he
himself always followed in his investigations. These rules are
chiefly curious by showing us the state of chemistry when
Bergman began his career. It is now universally admitted that
the only mode of advancing chemistry is experiment. Experi-
ments are now made with so much care that there is very seldom
any dispute about facts. The discussions which exist at present
in the science relate entirely to the consequences deduced
from these facts. The most striking discussion of the kind in
modern chemistry is the question whether chlorine be a simple or
a compound body; or rather, whether it contains oxygen or
not. Almost all the British chemists, all the French chemists,
and most of the German chemists, conceive it to contain no
oxygen; while Berzelius, and one or two individuals in Scotland,
consider chlorine to be a compound of oxygen and an unknown
basis, according to the original theory of Berthollet and the
French chemists. If Bergman’s old maxim were to be adopted
universally, this dispute would be cut short for the present.
This maxim was to consider every body as simple till some
evidence be produced that it is a compound, and not to admit
the existence of a principle in a body till it can be shown expe-
rimentally to exist in it. The experiments of Gay-Lussac, Davy,
&c. to decompose chlorine, though varied in every conceivable
way, are admitted on all hands to have been unsuccessful. We
have, therefore, no evidence at present that it is a compound.
Neither has the existence of oxygen in it been demonstrated by
experiments upon which any stress could be laid. The only
argument which Berzelius has brought forward is founded on a
law of his own invention. Yet he admits that this law does not
hold in the case of the nitrates and phosphates. If we suppose it
not to hold in the muriates, what becomes of his argument ?
This supposed law of Berzelius can be shown to be only a parti-
cular case of the atomic theory. We can by means of that
330 Biographical Account of {Nov.
theory explain all the cases which are conformable to his law,
and those likewise which do not agree with it ; and we can
explain the composition of the muriates just as easily on the
hypothesis that chlorine is simple as that it is compound.
Chlorine, indeed, for any thing we know to the contrary, may
be a compound, and may contain oxygen as one of its econsti-
tuents ; so may azote, and so may iron. But our opinions
respecting the composition of bodies must be conformable to the
evidence which is laid before us; otherwise we forsake the
road of science, and get into that of fancy and romance.
The rules for investigating chemical phenomena are sufficiently
simple, and may be reduced to the following.
(1.) Every fact must be established by satisfactory experi-
ments.
(2.) A body must be considered as semple unless satisfactory
evidence can be brought to show that it is a compound.
(3.) The most satisfactory way of showing a body to be a
compound is to separate its constituents, exhibit them in a
separate state, and to show that by uniting them again together,
the original compound body is produced.
(4.) When a substance cannot be exhibited in a separate state,
it is always hazardous to draw any peremptory conclusions
respecting its existence. Our conclusions should be given only
as hypothetical or conjectural ; because the only unequivocal
evidence of the existence of a chemical body is wanting. The
existence of the principle called phlogiston, so universally
admitted at one period, is an example in point, which should
make us cautious in our conclusions.
2. On Carbonic Acid.—Bergman seems to have been the
first who considered this substance as an acid. His opinions
on the subject were communicated to foreign chemists in 1770,
and his first essay on this acid made its appearance in 1773.
It would be needless, considering the present state of our
knowledge, to give a minute account of this essay, though at
the time of its publication it must have been exceedingly valuable.
He describes the mode of procuring this gas, shows that it
possesses the properties of an acid ; that water at the tempera-
ture of 41° absorbs rather more than its bulk of it; that the
specific gravity of such water is 1:0015; that the specific
gravity of carbonic acid gas is rather more than 1-5, and that it
combines with the different bases, and forms salts. He prepared
and deseribed bicarbonates of potash and soda, carboriate of
.ammonia, carbonate of barytes, carbonates of magnesia, zinc,
and manganese. He determined the order of the affinities of
earbonic acid for the bases; and he showed that it is the
weakest of all the acids known when he wrote.
3. Of the Analysts of Waters.—This paper, first published in
1778, was of great importance at the time of its appearance. In
it the method of analyzing waters is first laid down. Before the
1818.] Sir Torbern Bergman. 334
appearance of this treatise, the method of analysing waters may
be considered as unknown. Several attempts, indeed, had been
made with more or less success ; but no general formula appli-
cable to waters in general had been thought of. Considerable
improvements have been recently made on the method of analyz-
ing mineral waters. This, indeed, was the natural consequence
of our more accurate knowledge of the exact composition of the
different salts which exist in mineral waters, and of the simplest
methods of detecting them and estimating their quantity.
Kirwan published a treatise on the same subject about the
beginning of the present century. But his methods are rather
too complicated for actual practice, and they seem scarcely
compatible with much precision. Dr. Murray’s formula, published
m the eighth volume of the Transactions of the Royal Society
of Edinburgh, is, as far as it goes, the best and easiest method
of analyzing mineral waters. It seems unnecessary in the
present state of our knowledge to enter into any particulars
respecting Bergman’s paper. For the same reason we may omit
his papers on the Waters of Upsala, on the Acidulous Spring in
the Parish of Denmark, on Sea Water, on the Artificial Pre-
aration of Cold Medicated Waters, and on the Artificial
reparation of Hot Medical Waters. These papers were of
much utility at the time of their publication ; hut at present the
science has made such progress, that they have lost a great deal
of their interest.
4. On the Acid of Sugar.—This paper was originally written
as an inaugural dissertation, which was defended in 1776 by
J. A. Arvidson. Hence, doubtless, the reason why nothing was
said about the discovery of oxalic acid, and why it was generally
supposed at first by the chemical world that Bergman himself
was the discoverer of that acid. It is now known that the acid
in question was discovered by Scheele, who merely commutii-
cated the process to Bergman. In this paper Bergman describes
_ the method of preparing oxalic acid, the properties by which it
is characterized, and the salts which it forms with 22 bases, all
that were known to exist at the period when this dissertation
appeared.
5. On the Preparation of Alum.—This dissertation, which
has been mentioned repeatedly in the preceding biographical
account, contains a history of alum, a chemical examination of
its composition, a description of its ores, a minute description
of the processes followed by manufacturers, and a set of experi-
ments undertaken with a view to improve these processes. Hven
at present this dissertation will be allowed to be excellent, and
alum makers would probably derive useful hints from a careful
perusal of it:. He was aware of the importance of potash and
ammonia, and owns that the facts would lead to the conclusion
that alum is a triple salt. But he rejects this supposition on
account of the fact that ammonia is equally efficacious in pro-
332 Biographical Account of [Nove
moting the crystallization of alum with potash. Soda and hme
he found possessed no efficacy whatever. It is rather surprising
that this did not lead him to the true conclusion, that there are
two species of alum, one containing potash, and the other
ammonia. ‘This conclusion was first drawn by Vauquelin.
Whether the analysis of alum by Berzelius, which is commonly
received, be correct, is a point that I rather believe will require
some further examination. The subject is of importance,
because the weight of an atom of alumina, and even the mode of
manufacturing alum, must be a good deal influenced by it.
6. On Antimoniated Tartar—This is the name by which
Bergman distinguished tartar emetic, the only antimonial prepa-
ration much used in medicine. ‘This dissertation is of consider-
able importance. He details the different processes given for
- preparing this salt, and shows that they were so discordant and
maccurate, that the same substance could not be obtained at
different times. His process is to mix powder of algaroth (the
white powder which precipitates when chloride of antimony is
mixed with water) with cream of tartar, to boil the mixture for
half an hour in water, then to pour off the liquid, evaporate to a
pellicle, and crystallize. It is now known that tartar emetic is
a salt composed of bitartrate of potash (which acts the part of an
acid) and protoxide of antimony.
7. On Magnesia.---This dissertation, first published in 1775,
may be considered as the third chemical dissertation on magnesia.
The first was by Dr. Black, in 1755; and the second, by Mar-
graf, in 1759. Bergman describes the method of obtaining
magnesia, details its properties, and gives a pretty full account
of the salts which it forms with the different acids. The only
paper of much consequence which has made its appearance upon
magnesia since Bergman’s paper, is a small book published by
Butini, of Geneva, in 1781, entitled ‘‘ Nouvelles Observations
et Recherches Analytiques sur la Magnesie du Sal d’Epsom.”
But most of the magnesian salts have been analyzed with toler-
able accuracy by modern chemists.
8. On the Forms of Crystals.—This paper was first published
in 1773, and is remarkable, because it contains the very same
discovery which afterwards led Haiiy to his theory of crystals.
He shows that the primitive form of calcareous spar is a rhom-
boid, the faces of which have angles of 1014° and 782°, that all
the different crystals of calcareous spar may be formed upon such
a base, and that a nucleus having the primitive form may be
extricated mechanically from all the different forms. In short,
this curious paper, which he informs us was the fruit of many
years’ assiduous observations on.crystals, may be considered as
exhibiting the first outline of Hauy’s theory.
9. On Siliceous Earth—This paper was published in 1779.
Bergman in it states with precision the chemical characters of
silica, shows that it differs in its properties from the other earths,
2
1818.] Sir Torbern Bergman. 332
that it cannot be converted into them, and, therefore, that it is
entitled to be considered as a peculiar substance. He adopts
Scheele’s notion, that silica is a compound of fluoric acid and
water; an opinion soon after refuted.
10. On the Hydrophanous Stone.—This name was given by
Sir John Hill to certain stones which are opaque in the air, but
become transparent when plunged into water. They were sold
at an extravagant price. But the secret of these stones is here
revealed by Bergman. Various minerals, particularly opals and
chalcedony, exhibit this property. Such stones have hollow
cavities in them. When these cavities are filled with air, the
stone is opaque, in consequence of the very different refracting
power of the stone and the air. But when the cavities are filled |
with water, the stone becomes transparent, because the refract-
or of water approaches more nearly that of the stone
itself.
11. On the Earth of Gems.—This elaborate paper was first
published in 1777, and is not the least remarkable of Bergman’s
labours. It contains the first attempt to give an accurate
analysis of the very hard stony bodies. The processes, though
rude, exhibit obviously the rudiments of our present processes.
Indeed Bergman must be considered as the original author of
the processes for analyzing mineral bodies by the moist way. It
would be useless to enter into details respecting his results, as
it is not surprising that they should be all inaccurate. Indeed
as he gives a very imperfect account of the bodies to which he
affixes particular names, itis not always easy to conjecture what
the mineral really was that he subjected to analysis. Pro-
fessor Jameson, for example, conjectures that the hyacinth of
Bergman was in reality a cinnamon stone. But I had an oppor-
tunity of seeing the very collections of hyacinths from which
Bergman’s specimens for analysis were selected ; for they are
still in the University of Upsala, in possession of Professor
Afzelius ; and there cannot be the least doubt entertained that
they are true hyacinths.
the next dissertation on the earth of the tourmaline stone
needs not be particularly noticed, as the analysis was conducted
paeely in the same way as the analyses of the gems.
12. Onthe Fulminating Calx of Gold.—This paper, first pub-
lished in 1769, contains the first accurate account of the
properties of fulminating gold, the first attempt to ascertain its
composition experimentally, and to explain its fulminating power.
According to Bergman, fulminating gold is a compound of
oxide of gold and ammonia. Ammonia is a compound of azote
and phlogiston. When heat is applied, the phlogiston reduces
the gold ; and the azote being suddenly disengaged in its elastic
state, occasions the explosion. The theory of this remarkable
powder has advanced but little since Bergman’s time. Analo
would lead to the suspicion that it is a compound of gold and
334 Biographical Account of fNov.
azote, or of oxide of gold and azote. But we have no proof
that this is really its composition.
13. On Platina.—This dissertation was published in 1777,
and is chiefly valuable as explaining the effects of the alkalies
when dropped into a solution of platmum. It was Bergman that
first showed that sal-ammoniac precipitates platinum by forming
with it a triple salt which is but little soluble in water. Potash
produces a similar effect ; but soda and lime- do not form triple
salts, but precipitate, according to him, the metal in the state
of an oxide.
14. On the White Ores of Iron.—This paper, first published
in 1774, Contains the first account of the properties of the metal
called manganese. These properties’ were partly detected by
Bergman, partly by Scheele, and partly by Gahn. It was Gahn
that first obtamed manganese in the metallic state. It would
be needless to give the substance of this elaborate and valuable
paper; because we are now possessed of more accurate means
of analysis ; and the properties of manganese are known with
greater precision than they were when Bergman wrote. Berg-
man’s method of separating iron and manganese from each
other by solution in nitric acid and calcination was used till
Vauquelin substituted another, which, however, does not suc-
ceed better.
15. On Nickel.—This paper was published in 1775, It con-
tains an elaborate set of experiments to obtain nickel in a state
of purity. These experiments were all made in the dry way;
and were not perfectly successful. But our author succeeded
in establishing the peculiar nature of this metal by showing that
its properties became more and more peculiar the more com-
pletely it is freed from foreign bodies. '
16. On Arsenic—This paper, originally published in 1777,
tontains the fullest and best account of the properties of arsenic
which has yet appeared. It contains, indeed, certain mistakes
and erroneous deductions, which flowed unavoidably from the
state of the science in 1777. Except the correction of these
mistakes, and more exact numeral results, the chemical know-
ledge of arsenic has advanced but little since the days of
Bergman.
17. On the Ores of Zinc.—This dissertation was published in
1779, and contains an analytical examination of all the ores of
zinc which were then known. He succeeded in pointing out
the constituents of all these ores with sufficient accuracy ;
though his methods were not sufficiently precise to enable him
to obtain the accurate proportions of each.
18. On Metallic Precipitates.—This paper, first published in
1780, is one of the most elaborate productions which Bergman
has left us. It may be considered as the first attempt to inves-
tigate the nature of the metallic oxides, and to point out the
state in which the different metals are precipitated by various
1818.) Sir Torbern Bergman. 335
reagents. Though it contains a great deal of erroneous theory,
yet, as the experiments are all distinctly and numerically stated,
we have it in our power to strip them of the theory in which
they are involved, and to apply them to the present state of our
knowledge. They must have contributed very materially to
guide the subsequent investigations of chemists; though the
numbers given by Bergman are not sufficiently precise to enable
us, from them alone, to deduce the composition of the metallic
oxides.
19. On the Art of assaying in the humid Way.—This disser-
tation appeared likewise in 1780, and is no less than a complete
treatise, explaining the method of analyzing the ores of all the
known metals. It was the first treatise of the kind that appeared,
and constituted the groundwork of all that has since been done.
It would be useless to examine it here. Almost every part of
the treatise has been improved upon ; almost every formula has
been modified or altered. But it must be at once obvious how
much the art of analysis owes to Bergman for this commence-
ment.
20. On the Blow-pipe.—This paper had been sent in manu-
script to Baron Born in 1777, by whom it was published in
1779. It contains directions how to make experiments with
the blow-pipe, and gives a very particular account of the pheno-
mena exhibited by the different stones, metals, and ores, when
heated by the blow-pipe, either alone, or mixed with the different
fluxes. Since that time, the use of the blow-pipe has been still
further improved by Assessor Gahn. His essay on the subject,
published in a preceding volume of the Annals of Philosophy,
we recommend to the careful study of every person who wishes
to become expert in the use of this very important instrument of
investigation.
21. On the Analysis of Iron.—This important dissertation,
published in 1781, contains the experiments, by means of which
the difference between iron, cast iron, and steel, was accounted
for. Bergman first detected the presence of plumbago in cast
iron and steel, and he first showed that iron yields more hydro-
gen gas than either cast iron or steel. The experiments were
very numerous ; and as far as they went, they are sufficiently
satisfactory.
22. On the Cause of the Brittleness of Cold Short Iron.—
This paper, like the last, was published in 178]. When cold
short iron is dissolved in sulphuric acid, a white powder remains,
which, when heated with charcoal, was reduced to a metallic
button. To this substance Bergman gave the name of siderum;
and he showed that when added to iron it renders it cold short,
It was soon after shown, that this supposed new metal is merely
a phosphuret of iron. ‘Hence it has been inferred, that iron is
rendered cold short by uniting with phosphorus.
This paper nag been already carried to such a length, that it
336 Dr. Pescher on the State of Potash in Plants, [Nov.
will be possible to give nothing more than the titles of the
remaining dissertations of Bergman, with the date of the publi-
eation of each.
23. On the different Quantity of Phlogiston in Metals. 1783.
24. On Sulphuret of Tm. 1781.
25. On the Sulphurets of Antimony. 1782.
26. On the Products of Volcanoes. 1777.
27. On Elective Attractions. 1775.
28. On the Analysis of Lithomarga. 1782.
29. On Asbestus. 1782.
30. Thoughts on a Natural System of Minerals. 1784.
31. On the Combination of Mercury and Muriatic Acid. 1769.
32. On the proper Mode of burning Bricks. 1771.
33. On the Acidulous Waters of Medevi. 1782.
34. On the Medicinal Springs of Lokarne. 1783.
35. On Cobalt, Nickel, Platina, and Manganese; and on
the Nature of their Precipitates. 1780.
36. Chemical Analysis of Indigo. 1776.
37. On Vegetable Soils. 1771.
38. On the Mountains of Westgothland. 1768.
39. On the latest Chemical Discoveries. 1777.
40. Mineralogical Observations. 1784.
ArticLe II.
On the State in which Potash exists in Vegetables, and on the
Saccharine Matter of the Potatoe. By Dr. Peschier.
(To Dr. Thomson.)
SIR, Edinburgh, dug. 12, 1818,
Tue enclosed was sent me by Lord March, that it might be
transmitted to you; the author being desirous that, if approved
of, the discovery contained in it might have a place in your
journal. Iam, Sir, with esteem,
Your obedient servant,
JoHN PLayFAIR.
ee
(To Lord March.)
MY LORD, Geneva, July 20, 1818.
You are too great a friend of the sciences, and I take too
much pleasure in communicating to you the discoveries which
may originate in this city; to allow you to remain ignorant of
some new facts ascertained in the laboratory of my brother, and
which will soon be communicated to the public.
The chemical analysis of vegetables having been for some
1818.) and of Sugar in the Potatoe. 337
years a favourite pursuit of the chemists, different vegetable
principles have been discovered in different parts of plants ; but
hitherto it has not been demonstrated in what state potash occurs
in vegetables ; and though it has been found inthe ashes of
plants, its presence had not been ascertained either in their
expressed juices or their decoctions. A set of experiments made
upon a certain genus of plants with a view of studying its
medical virtues has led to the discovery of potash in these
different liquids, and has suggested an easy mode of determin-
ing the acid with which the potash was united. .
All the juices (the word juzce denotes the liquid expressed
from a plant, but not from its fruit), or the decoctions of the
different parts of a vegetable, are more or less acid, reddening
paper stained blue with litmus, &c. It was necessary to find a
substance which should not only combine with the disengaged
acid, but which should have a greater affinity for that acid than
potash itself has. The acids which occur most commonly in
plants being the carbonic, the tartaric, and the oxalic, it was
necessary besides that this substance should form an insoluble
salt with each of these acids. Pure magnesia answers this pur-
pose completely. If then we agitate in the cold, or boil together
a vegetable juice or decoction, and a quantity of pure magnesia,
we obtain, after the separation of the deposite, an alkaline
liquid, which possesses all the characters of a solution of
carbonate of potash. By examining the magnesia in the requisite
manner, we can easily determine the acid with which it has
combined. (The tartrates and oxalates of magnesia are insoluble,
when there is no excess of acid—an excess which it is of
importance to avoid.)
The insolubility of pure magnesia and of a part of the salts
which it forms when united with acids, renders the process very
accurate, and of very easy execution.
If the salts contained in the vegetables be sulphates or nitrates,
they not only do not redden vegetable biues (because there is no
excess of acid present); but magnesia is not capable of decom-
posing them. ‘This isthe case with borage, &c.
This discovery, besides its importance in the analysis of plants,
facilitates the means of judging of the quantity of potash con-
tained in vegetable juices. Hereafter, incineration will not be
necessary in order to obtain that potash. The choice which a
philosophical society in Holland made of this problem as a. prize
question (in 1817), proves the interest with which it was viewed.
Second Discovery.—In consequence of a careful analysis,
Vauquelin drew as a conclusion, that potatoes are composed of
starch, of parenchyma, of a peculiar animal matter, and of
certain salts. These different substances did not explain the
cause of the spirituous fermentation which they undergo, if they
are exposed, sufficiently diluted with water, and mixed with a
little barley meal to the requisite temperature. Hence it has
VoL. XII. N° V,
338 Dr. Thomson’s Observations on the Weights of [Nov.
been proposed as a prize question, to discover the substance
which in potatoes supplies the place of sugar, to which alone the
spirituous fermentation is conceived to belong. A set of experi-
ments on potatoe meal, obtained by rasping, washing, drying,
and grinding, has shown that these bulbs contain sugar and
gum in the proportion of 64 gr. of mucous sugar, and of 220 gr.
of gum, in the pound weight of potatoe. These two principles
were discovered by digesting potatoe meal in six or eight parts
of cold water for 24 hours in a cool place, evaporating the
water to dryness, and treating the residual mass successively
with alcohol and water. Now it is the existence of these two
principles which occasions the commencement of the spirituous
fermentation, assisted by the barley meal. Their action upon
the starch, and the changes induced in it, account for the quan-
tity of spirit produced.
These two discoveries, my Lord, have a real connexion with
political economy; and they mterest the sciences, as they consti-
tute incontestible matters of fact. I may have the honour
hereafter of transmitting an extract of the memoir which m
brother proposes to read at the annual meeting of the Helvetic
Natural History Society, on the tribe of corns and_ their
products.
Our means of public education will be considerably improved
by the choice which has been made of a very convenient place
for experimental lectures on chemistry, physics, astronomy, &c.
by the association of about 200 persons connected with the
same place, who receive all the scientific journals of the world,
and who invite foreigners of every description for the election of
new professional chairs, and even of new faculties of science
and literature. Our academy will see with pleasure foreigners
in its bosom (provided they be distinguished by their knowledge)
reading public lectures on the sciences, and thus adding to the
scientific resources of Geneva. We are at present purchasing
in Paris a great many physical and astronomical instruments,
which were wanting for our lectures. Already we have begun
to form a cabinet of natural history, mineralogy, &c. The place
is. very. large; and we are receiving from all quarters objects
worthy of a place in this interesting museum.
Preseuier, D.M.
ArtTicce III.
Some Additional Observations on the Weights of the Atoms of
Chemical Bodies. By Thomas Thomson, M.D. F.RS.
Regius Professor of Chemistry in the University of Glasgow.
Tuoucsu little more than five years have elapsed since I pub-~
lished. my first tables of the weights of the atoms of different,
1818.] the Atoms of Chemical Bodies. 339
chemical bodies in the second volume of the Annals of Plhilo-
sophy, the subject has since that time been investigated with so
much skill and perseverance by Dr. Wollaston, Professor Berze-
lius, and several other chemists, that improvements have been
made in almost every individual number. 1 conceive, therefore,
that it will be interesting to chemists if I lay before them an
epitome of the present state of the subject. This I shall do by
giving a new table of the weights of the atoms of different bodies
such as they have been established by the most accurate experi-
ments hitherto made. I am far from flattering myself that the
numbers which I shall give are all accurate; on the contrary, [
have not the least doubt that many of them are still erroneous.
But they constitute at least a nearer approximation to the truth
than the numbers contained in the first table. it is only by
successive, and probably very slow approximations, that we can
expect to reach the truth at last. Every new step is something
gained; and, therefore, deserving of attention. I am far from
being apprehensive of being found fault with by those who
understand the nature of chemistry, and the true mode of improv-
ing it, for having formerly given numbers for the atoms of bodies
founded on the best data which I could procure at the time, and
for abandoning these numbers for others furnished by more
accurate experiments. We may expect, now that accuracy is
the great object of chemical experimenters, that more and more
precise results will be obtained as we proceed. Many, of
course, of the numbers which I now give will be to be abandoned
hereatter, and new numbers substituted, founded on experiments
approaching nearer to absolute accuracy. Meantime we must
be satisfied with the best facts which the science can furnish.
I am even of opinion that it has a very material tendency to
advance the science to lay before chemists the present state of
our knowledge, and the value of the data upon which our con-
clusions are founded.
Weight of an atom.
PURGES 25 ones ale tidate ate mete L000
PCMIGHEE.. masala ees ee 2 De
PUGS or rats ee ie anya ty ee Th B25-?
ee Opemanetts 24, FOO On ee cee. OZ"
a SEE SE DN A a ot he et ph eR Oe en i Se
* The weight of an atom of hydrogen is derived from the
composition of water. It has been established, that water is
* This number depends upon the specific gravily of chlorine gas. Gay-Lussae
and Thenard found it 2:47, 1 think Dr. Prout’s reasons for considering it as 2°5
are satisfactory. Davy has shown that protoxide of chlorine is a compound of two
volumes of chlorine and one volume of oxygen. Now if we consider it as a com-
pound of one atom chlorine +- one atom oxygen, it is obvious that an atom of
chlorine will weigh 4-5, ’
+ This is the number obtained by Gay-Lussac from the combination of iodine
and zinc, which he found a compound of 100 iodine + 26°52 zinc. Now 26°52:
100 :: 4-125 : 15-625. [have very slightly modified Gay-Lussac’s numbers to make
the atom of iodine a multiple of *i25,
¥ 2
340 Dr. Thomson’s Observations on the Weights of [Nov.
Weight of an atom.
ST OARHOS os SSOP ISTE POP ae ee 0:750
Gr Boron SE PHPeeI Ts ess a aA 0°875 >
Puno OPO OF eee a 00
formed by the union of two volumes of hydrogen gas and one
volume of oxygen gas. I consider it, with Dalton, as a com-
pound of one atom of hydrogen and one atom of oxygen. Hence
the weight of an atom of hydrogen will depend upon its specific
gravity. Biot and Arrago found the specific gravity of hydrogen
gas 0°074; that of air being 1. Now if the specific gravity of
oxygen gas be I-11], and if two volumes of hydrogen gas are
equivalent to one atom, it would follow that an atom of hydrogen
weighs 0°133., I have been at much pains in endeavouring to
determine the specific gravity of hydrogen gas, but never could
find it lower than 0:073, which differs but little from the deter-
mination of Biot and Arrago. But I do not think that abso-
lutely pure hydrogen gas has ever been weighed. It usually
contains traces of phosphorus, iron, zinc, &c. which must mate-
rially affect its weight. On that account I think that Dr. Prout’s.
method of determining the specific gravity of this gas from that
of ammoniacal gas is more likely to be correct. In ammonia we
are sure that the hydrogen is pure. It is likewise twice as
dense in ammonia as it is in hydrogen gas. This doubles the
chance of precision. When the weight. of hydrogen gas is
deduced from ammonia, that of oxygen gas is found to be 16
times heavier. Hence the number in the table for the weight of
the atom.
> The data upon which this number is founded are not quite
satisfactory. Covansa boracic acid, according to Davy’s expe-
riments, is composed of acid 57 + 43 water. If it be a
compound of one atom acid + two atoms water, the weight of
an atom of boracic acid will be 2°998. From the analysis of
borate of ammonia by Berzelius, the weight of an atom of the
acid is 2°66. The mean of these two is 2°829. From the expe-
riments on the combustion of boron, there is reason to believe
that the acid contains at least two atoms of oxygen. Ifso, it
must be a compound of 2 oxygen + 0°829 boron. The number
0°875 was chosen in preference to this number; because it is a
multiple of 0°125, which all the atoms seem to be.
© Neither are the data for this number to be depended on.
Every thing shows us that silica in stony bodies acts the part of
anacid. Yable-spar isa compound of 50 silica + 45 lime; if it
be a bisilicate of hme, the weight of an atom of silica will be
2-015, for 45 : 50 :: 3°625: 4:03. Again, nepheline is a com-
pound of 49 alumma + 46 silica. Suppose it a silicate of
alumina, silica will weigh 1:994 ; for 49 : 46 :: 2°125 : 1:994.
Now the mean of these two numbers is 2°0045. Hence we may
1818.] the Atoms of Chemical Bodies. 341
Weight of an atom.
Prbaigephoras +. «6 s:.'.!,'s\ dsieinie's' 0 eee es
ORAMEES 660 o6 dd 2 iskeedddalees etal aa
BOW Salphir :..°.'sjo's'ac%slalpiaisisipis'c's e's’ 2
Dy Welbarrim: he's cies dateateoelatate! eta SO
1s Arsenic scocee code tad cetoeel eee ETD
conceive the weight of an atom of silica to be 2:000. But as it
must contain at least one atom of oxygen, it is obvious that an
atom of silica must weigh |.
4 There can be no doubt that this is the true weight of an
atom of phosphorus. Perphosphuretted hydrogen gas has the
specific gravity of 0-9022. The bulk of hydrogen gas is not
altered by converting it into perphosphuretted hydrogen. Hence
t is composed by weight of
BRC OBC: wires jeans whee sean Hoaeor) vl
PRGSPROLUA, jx: «ye 'denit siginatsiarsk BOS: Sot LZ
I conceive this gas to be a compound of one atom hydrogen
and one atom phosphorus ; but 1 : 12 :: 0°125: 1:5. Perphos-
phuretted hydrogen gas unites with 1 volume, 14 volume, and
2 volumes of oxygen gas. Now half a volume of the oxygen
gas unites to the hydrogen; the remainder combines with the
phosphorus ; so that one volume of phosphorus unites with half
a volume, with 1 volume, and with 14 volume of oxygen, forming
hypophosphorous acid, phosphorous acid, and phosphoric acid.
This is the. same thing as if we said that one atom of phosphorus
unites with one atom, two atoms, and three atoms of oxygen
respectively.
© I think it probable that oxide of tellurium is a compound of
100 tellurium + 25 oxygen. Berzelius found 100 tellurium
+ 24:8 oxygen, which comes sufficiently near. Now if this
oxide be a compound of one atom metal + one atom oxygen, it
is obvious that an atom of tellurium will weigh 4.
f Experiments on arsenic seem to be attended with more
* This is the number which Dr. Wollaston selected after a careful exami-
nation of the experiments hitherto made on the subject. Mr. Phillips has, with
his usual acuteness, shown it to tally very nearly indeed with the best experiments
of Davy, Gay-Lussac, Dalton, and his own.—(Royal Institution Journal, v. 162.)
I am disposed to consider it as correct. The only experiment which induces me
to hesitate is one by Berthoilet. He decomposed nitre by heat, and obtained a
gas composed of one volume azote and two volumes oxygen : our number would
require one volume azote and 24 volumes oxygen. I shall givea translation of this
paper of Berthollet in the next article of the present number, because I wish to
draw the attention of chemists to it. 1 do not know very well how to account foc
this discordance between the results of Berthollet and those of other chemists. Per-
haps the half volume of oxygen wanting may have combined with the potash. I
may, hereafter, relate the result of a set of experiments which I mean to undertake
on purpose to elucidate this point. ‘Till then I think it safest toabide by the num-
ber 1°75 for the weight of an atom of azote,
342 Dr. Thomson’s Observations on the Weights of [Nov.
Weight of an atom,
ede LOGRS SINT you 'e oo uae he ee eaten 5:000
Dae PN OUMUT as se Ce ace, tl cid So ehen eae ck 3°00
Ley MORE a eco cc acninic yates nie Meat ones 2-625
VG SRAACRDIINE 55 posed 'e Woe 'evs nenerahe noe aaa 8°750
DE APSO TUTEN wee tase cociain j2accucs pei eeois MRL 5:500
LO AVES UER .).\n'e'ais.nae oie, os. cre aarne 1-500 §
ae eoteir Sci) Saree le Ae) teeta 6°000 »
BD RI Res Sc Davo Se a Lo 4-000 '
difficulty than those upon other metals. The number 4°75
results from the compounds which arsenic forms with oxygen ;
but it does not agree well with the chloride of arsenic. Besides,
if 4°75 be the weight of an atom of arsenic, neither arsenious nor
arsenic acid will contain whole atoms of oxygen ; for the first _
will be a compound of 1 atom arsenic + 11 atom oxygen, and
the second of | atom arsenic + 21 atoms oxygen. ‘These ano-
malies render it very unlikely that an atom of arsenic really
weighs 4°75.
& But few changes have been made upon the weights of the
atoms of these six alkaline metals. The supposition that an
atom of sodium weighs three, tallies very well with experiments,
if we suppose soda to be a compound of | atom sodium + | atom
oxygen. On that supposition soda will weigh 4, which agrees
with the weight resulting from the composition of the salts of
soda. The number for strontium results from the mean of Stro-
meyer’s analyses of the salts of strontian, and my own. The
number for magnesium is founded on Berzelius’s analysis of
sulphate of magnesia.
» This number is very convenient, and it tallies as well with
the analyses of the salts of potash as any other.
Acid. Potash.
Kirwan found sulphate of potash composed of.. 45°20 + 54°80
hove 3 Le a one 9 Aa ee Aes eae ery Oey 45°30 + 54:70
ESS Oil Ap tata sidocls'ohch''s'cs ds wate thay andes vee 45°72 + 54:28
Mean yi5 cnehe sen 45°40 + 54:60
If it be a compound of 5 acid + 6 potash, its? ,-.
constituents are...... Spies iat a hind : biekidve etd ‘ 45°46 + 54°54
T consider this as almost an exact coincidence.
i This number agrees equally well for soda.
Water, Acid, Soda,
sts Wn sulphate of soda ining: 56 2476 4 19-24)
If it contains 5 acid + 4 soda, its con- . :
' stituents willbe ...... eet ibaccesrsins - “pe
1
1818.] the Atoms of Chemical Bodies. 343
Weight of an atom.
OU Me oye o's ide valent Wate a duane ik tmennelegO.
2D BVATY LES « voresere oie ateiew evernio are savee OO 9°750!
53 Strontian ........ Lia\ctetarcre oe ONY 6°500 ™
2A Mapnesia. Ji)... e ak antes eee tl Oe
Ae SSCL, “eal sholadsi a atasiaherel ets Wane 4-000
BED CP GLELAS. capo Waheratate ata eke gh daletcnaaters of 5:000 °
* If sulphate of lime be a compound of 5 acid + 3-625 lime,
its constituents will be
Acid. Lime.
57°97 + 42-03
Berzelius’s analysis gives US .....seeeeee eens 58:00 + 42-00
which may be considered as an exact coincidence.
' If sulphate of barytes be composed of 5 acid + 9-75 barytes,
its constituents will be
Acid, Barytes,
33°90 + 66°10
Mr. Arthur Aikin’s analysis gives ........000. 33°96 + 66:04
Berzelius and Fourcroy found. .............. 34:00 + 66:00
™ Carbonate of strontian, supposing it a compound of 2°75
acid + 6°5 strontian, should consist of
Acid. Strontian,
29°73 + 70°27
I found its constituents to be...... ces eeeeee 29:90 + 70:10
If sulphate of strontian be a compound of 5 acid + 6°5 stron-
tian, its constituents should be
Acid, Strontian,
43:48 + 56°52
Stromeyer found it ...........45 eeeeesseeee 43°00 + 57:00
These coincidences are sufficiently near. The deviations are on
opposite sides; so that the mean of the two would almost tally
with our theoretic number.
Acid. Magnesia,
* Berzelius found sulphate of magnesia com-2 pe. 29,
Me is in o's pind) Zininieliag: ave. Wai slaanincs ig Na adi
If it be a compound of 5 acid + 2-5 mag- ‘ :
nesia, its constituents will be. ..........0. it 66-60 + 33°30
This coincidence I consider as exact.
° According to Berzelius (Afhandlingar, iv. 236), sulphate of
yttria is composed of equal weights of acid and base. Hence
an atom of yttria weighs the same as an atom of sulphuric acid.
The weight of an atom of yttrium is conjectural. It is founded
on the supposition that yttria is a compound of 1 atom yttrium
344 Dr Thomson’s Observations on the Weights of [Nov.
Weight of an atom.
OF MG CIN UID (232 Zi efapeloteter selene a televere 2°250
8 Getta. casey svetetes stetsh Ha AA Ree 3°250 P
OO CAN MIN Ms Cone Shee ene oes }125
SO PAluminas 24 hs ee AS a ee 27125 4
SE Zarconinm eek Ek oe Rae 4-625 ?
32 Pareomia 3.2 382 Sew A Uren eS oe G5 2
Si Mees Ne ee ee eit ce cake Petes 3°500
of Protomde of tron i c2it) 3 Petters’ 4-500 ©
AlMeCLORIGe: OF ATONS 6 )c iu, Sole ale sehen 10-000 §
SAO DADSICG 4 aig ove bee ioe prea he aa eiarea aad 3°3753
3? ‘Protoxide of nickel.) S000 0. 00. 3: Lovo ©
+ 1] atom oxygen; but we have no means of determining whether
the supposition be well or ill founded. It would be necessary to
determine the weight of oxygen and metal in yttria before we
could be quite certain.
-? According to Berzelius, sulphate of glucina is a compound of
Acid. Glucina.
100 + 64-100
If it be composed of 5 acid i 3°25 glucina, es 100 + 65-000
composition will he.....-.. Spies sietatetel sl lale i
4 This number is founded upon Berzelius’s analysis of sulphate
of alumina.—(Ann. de Chim. Ixxxiu. 14.)
Acid. Alumina.
He found it a compound of. ...........-. oe. 100 + 42°722
Now 100 : 42°722 :: 5:2:115. I take 2°125 as sensibly the
same with 2°115. Mr. Richard Philips informs me that he has
analysed the sulphate of alumina with a different result ; that the
quantity of alumina which he found in the salt was much greater.
Should this statement turn out correct, the weight of an atom of
alumina would be higher than it is stated above, and might even
amount to 3-5, the number in my original table,
* According to Berzelius’s analysis of sulphate of iron, the
weight of protoxide of iron is 44. He found it a compound of
28°9 acid + 25°7 protoxide of iron + 45:4 water. Now 28-9:
25-7 <2): 44. have adopted 4°5 as sufficiently near the
number. The mean of all the analyses of protoxide of iron
gives us 100 iron + 28°78 oxygen. Ifwe consider protoxide of
iron as a compound of | atom iron + 1 atom oxygen, and its
weight to be 4:5, then it will be a compound of 100 iron +
28°57 oxygen. These coincidences are sufficiently near.
’ My reasons for pitching upon this number for the weight of
an atom of peroxide of iron have been given in the Annals of
Philosophy, x. 98.
: I am not quite satisfied with this number, though it is
1818.] the Atoms of Chemical Bodies. 345
Weight of an atom,
38 | Peroxide of nickel ......0005 0. de. 9"750 *
MAU OTIANT «ons 0 wan aie nis labanemnins toe 3°625
40 Protoxide of cobalt.......... lee as penne eee
41 Peroxide of cobalt. ............. . 10°250
Bie RAM CANIENG) Ki, circle wwasncunolielotel eaese aia 3°500
43 Protoxide of manganese.......... 4-500 *
44 Peroxide of manganese .......... 5500
AES USHA S iets serovars isin Dahesh dts a ak Ap hee
46 Protoxide of uranium ............ 16°625 ¥
founded on the best data to be had, and cannot be very far from
the treth. Tupputi found sulphate of nickel composed of acid
100 + 87-26 protoxide of nickel. Now 100 : 87:26 :: 5: 4:362;
so that the weight of an atom of protoxide of nickel is 4-362:
4-375 scarcely differs from this number. I prefer it, because it
is a multiple of 0:125. ‘The average of the analyses of the prot-
oxide of nickel (omitting Proust’s) makes it a compound of 100
metal + 28°74 oxygen. This shows us that it must be a com-
pound of | atom metal + 1 atom oxygen. If so, the true pro-
portions must be 100 metal + 29°63 oxygen.
" This supposes it a compound of 2 atoms metal + 3 atoms
oxygen. It contains 11 umes as much oxygen as the protoxide.
~ This number is derived from the analysis of protoxide of
cobalt by Rothotf, who found it a compound of 100 metal +
27°3 oxygen. If it be a compound of 1 atom metal + 1 atom
oxygen, anatom of the metal must weigh 3-663 ; but the atoms
of carbon, oxygen, azote, phosphorus, and sulphur, which have
been ascertained with the greatest precision, are multiples of
0°125, or an atom of hydrogen. Hence I suspect that all the
atoms, if accurately ascertained, would be multiples of hydrogen:
3°663 not being a multiple of -125, I take 3-625, which is the
nearest multiple as the weight of an atom of cobalt: of course
the protoxide must be 4-625. Rothoff has shown that the oxygen
in the peroxide is 1} times_as much as that in the protoxide.
Supposing the peroxide composed of 2 atoms metal + 3 atoms
oxygen, its weight will be as in the table.
* Prom John’s analysis of sulphate of manganese, the weight
of protoxide comes out 4:6 ; from his analysis of the carbonate,
it comes out 4-495. I conceive, therefore, that 4:5 is probably
the true weight. The peroxide of manganese has never been
accurately analyzed ; but there can be little doubt that it contains
just twice as much oxygen as the protoxide. I believe the red
oxide of manganese, which is intermediate between the othertwo,
not to be a particular oxide, but a compound of protoxide and
peroxide. It does not seem capable of uniting with other bodies.
Y The experiments of Schoiibert lead to the conclusion that
346 Dr. Thomson’s Observations on the Weights of [Nov.
Weight of an atom.
A? Peroxide of uranium. .. : 2044. 0s 2. 384°250
UGS CMOMERINRTTD ec’ Suhel bos kaostootan ties voll oa ies dabei one OO
49 Protoxide of cerlum. ...... ae ame6:FhO #
50 Peroxide of cerlum.......eee0.% . 14500
$5) APRN oe ork ite abilities Filan sconciaiaiie Mersey? 2") 245)
BF Mxgide Ol 7G. 2c. Se we Ramee 60s ED ®
5S RAIN eas sce ow. trie vc CASTS d 2 os 43°000
54 Protaxide of lead. «| OOO
TG CULO. 3: eee a he LG *
POUT MtbOis i, 0 he Sin. poayent COOLOU
Means 7s 0c 20. 66°02
It was supposed that the gas remaining in the retort after the
process was precisely similar to that in the glass jar; because
the communication was very free, and the great change of tem-
perature which took place ought to have occasioned an equal
mixture.
* I presented on Jan. 17, 1778, to the Academy of Sciences, a memoir, in
which 1 showed that the acid of nitre could be entirely converted into gas by the
action of heat, or at least that the only portion not thus changed was quite insigni«
ficant: that by that method 580 cubic inches of gas might be obtained from an
ounce of nitre; that this gas consisted chiefly of oxygen, which afforded an expla-
nation of the effects of nitre upon charcoal and sulphur: that dried nitre contained
no sensible quantity of water; and that ata certain stage of the decomposition the
nitrate was changed into a phlogisticated nitre, or into a nitrite, which preseryed
its neutrality.-Memoires del Academie des Sciences, 1781.
352 M. Berthollet’s Experiments on the Proportion [Nov.
The volume of gas disengaged added to that of the air in the
vessels before the experiment forms a total volume of 5:07 litres,
which, according to the preceding analysis, are composed of
3°3716 litres of oxygen and 1:7354 of azote, from which we must
subtract 0:0629 of oxygen and 0:2368 of azote, which consti-
tuted the atmospherical air of the apparatus. Hence the nitric
acid was composed of 3°3037 litres (201-92 cubic inches) of
oxygen and 1:4986 litres (91-456 cubic inches) of azote. This
makes the composition of nitric acid in volume
NORGE a terticssts nie ciee pre.evcisie m0 LOU
The experiment was repeated with the same quantity of nitre ;
but to avoid the sublimation which took place in the former one,
the fire was much more cautiously raised; and in fact no subli-
mation took place. To ascertain the capacity of the retort and
tube with more precision, it was filled with water after the expe-
riment, which was afterwards poured into a graduated cylinder.
The result of this experiment was, that in nitric acid 100
litres of azote are combined with 222-96 of oxygen.
From a third experiment it results, that 100 litres of azote are
combined with 222°58 of oxygen.
. The mean of the three experiments gives for 100 of azote
(222-10 of oxygen.
If we convert these proportions into weights, we find that
nitric acid is composed of
Oxygen. Azote.
69-92 + 30:38
100-00 + 43.65
My experiments give a proportion of oxygen a, little smaller
than that which is adopted by Dalton, who admits for 100
measures of azote 133 measures of oxygen, a proportion which
differs little from the results of Cavendish and Davy.
Towards the end of the decomposition of the nitrate, the
receiver acquires a red colour; but as the nitrous gas indicated
by that colour is found in contact with an excess of oxygen, it
ought tobe again converted (at least chiefly) into nitric acid,
and of course produce little alteration in the ratio of the oxygen
and azote as indicated by the experiment.
This quantity of nitric acid which is again formed is so small
that it cannot even alter sensibly the absolute weight of the
acid, as determined by the weight of the gases disengaged.
This I ascertained by passing through a small quantity of water
all the gas disengaged during the process. This fact had been
already constated by Lavoisier and Bacquet, who were eim-
ployed by the Academy of Sciences to examine the memoir of
which I have spoken.
If we ey the products of this decomposition to determine ~
1818.] of the Elements of Nitric Acid. 353
the proportion of acid in dry nitrate of potash, we find, by cal-
culating the products of the first experiment, that 100 parts of
the salt are composed of
1 ST RI a ee ea a < imat
Motadhs 5... cs csle eben es a DUE
100:0
When we calculate the other experiments, the results vary
merely a few thousandth parts. Hence it follows from these
ee ene that nitre is composed of equal weights of acid and
otash.
This method gives, perhaps, a nearer approximation than
those which are founded on the composition of any other salt,
respecting which there must of necessity be a greater or smaller
degree of uncertainty.
—=
Note by the Editor—Though I cannot pretend to account for
the source of the fallacy, I have not the least doubt that the
constitution of nitric acid, as deduced from the preceding expe-
riments, is inaccurate. It has been sufficiently established that
an atom of oxygen gas may be represented by one volume, and
an atom of azotic gas by two volumes. We may of course
obtain the atoms that enter into combination, by simply doubling
the volume of the oxygen gas. If we do this, we see that,
according to Berthollet’s experiments, nitric acid is a compound
of 1 atom azote + 4-442 atoms of oxygen. Now it is quite
obvious that the fractional part of an atom amounting to 0-442
cannot possibly exist as a constituent. Instead of 100 azote +
222:1 oxygen, the true number ought to be 100 azote + 250
oxygen. Ifany one prefers the theory of volumes, as explained.
by Gay-Lussac, and adopted by Berzelius, to the atomic theory,
the objection is not in the least diminished; for, according to
that theory, one volume of azote can combine only with a cer-
tain number of volumes of oxygen, and not fractional parts of a
volume, as is indicated by the experiments of berthollet.
But it is easy to show by experiment that the composition of
nitrate of potash is not what Berthollet has deduced from his
experiments. I took 100 grains of pure and dry niire, poured
sulphuric acid upon the salt in a platinum crucible, and exposed
it to a heat at first low, but gradually increased till it became
sufficiently intense to decompose bisulphate of potash. ‘The
residual sulphate of potash weighed 83°6 gr.; but 83-6 of sulphate
of potash contain 45:6 potash ; therefore, nitre is composed of
Nitric acid ..... W eAGighiey sl G44
Peta -. 60. aN eer. hae
100°0
‘Vou. XII. N° V. Zz
354 M. Berthollet’s Experiments on the Proportions [Nov.
Proportions very different from those of Berthollet, namely,
Matric acid sxuten vie: wees 49°9
Patachrs to, sik. . Guiaitotek pao:
100-0
It is obvious that in Berthollet’s experiments 4-5 gr. of the
nitric acid were lost, and this loss seems to have fallen chiefly,
if not entirely, upon the oxygen. Let us deduce the weight of an
atom of nitric acid from my experiment. We have 45:6 : 54-4
:: 6: 7:158. The weight of an atom of nitric acid comes out
7°158, which I believe to exceed the truth somewhat. It
seems obvious, therefore, that my mode of experimenting has a
tendency to increase the quantity of acid somewhat above the
truth ; so that some of the potash must have been sublimed.
Probably the error might be diminished by employing sulphate
of ammonia instead of sulphuric acid to decompose the nitre.
It is obvious that a much lower heat at least would be requisite.
I intend to repeat the experiment in this way ; and may state the
result hereafter.
Im the mean while, as the errors in the two experiments lie on
different sides, the probability is, that the mean of the two will
come very near the truth. Such a mean will give for the com-
position of nitre,
NETIC AGI Ye waite, 5.0 cleo alent DOtED
Piatasha ioe 3) Nidhius adm atae amended ee oD
100-00
Now 47°85 : 52:15 :: 6 : 6-539. This weight, 6-539, though
not absolutely correct, is undoubtedly much nearer the truth than
either the number derived from Berthollet’s experiment or mine.
Dr. Wollaston made an experiment which was susceptible of
very considerable precision. He saturated a given weight of
bicarbonate of potash with nitric acid, and ascertained the
weight of the nitre resulting. Nitre turned out a compound of
100 acid + 86-764 potash. This is equivalent to
Nitric acid ........ tis vee, 60°S43
Potash? 09 42'5,£ a weeee 46°457
100-000
The error in this experiment lies upon the same side as in
mine, but it is smaller. Both errors are not more than sufficient
to counterbalance Berthollet’s error on the opposite side. There-
fore, if we take the mean of all the three, we must obtain a
result which will approach still nearer accuracy. This mean -
gives us niire composed of
4
1818.] of the Elements of Nitric Acid. 355
Nitric acid. ............ 526143
PGES sec cus eee ee sepa ay Ode
100-0000
Now 47-3856 : 52°6143 :: 6 : 6-662. I consider 6°75 as the
true weight of an atom of nitric acid. Now 6-662 approaches
very near that weight.
No person would believe who has not tried it how exceedingly
difficult it is to attain absolute precision in chemical experiments.
{am persuaded that we can reach that very desirable object in
no other way than by taking eare that the errors fall upon differ-
ent sides, and then taking the mean of a greater number of
experiments. If we were in possession of three other sets of
experiments made with the same care as those of Berthollet,
Wollaston, and my own, upon the analysis of the same salt, I
am persuaded that by taking the mean of all the six, we should
approach the truth very nearly indeed. The error even from the
three does not much exceed one per cent.
ARTICLE V.
A Barometrical Measurement of the Profile of Mount Jura, on
the Line of Geneva,—Lons-le-Saunier, by successive Observa-
tions, whale corresponding ones were fae s at Geneva, Stras-
burg, and Paris. Executed in 1813 with a Barometer of
Fortin, during the Course of a- Geodesical Examination.
With a Critical Comparison of the Barometrical Measure-
ments with those obtained by Zenith Distances. By M. Delcros,
Captain ofthe Royal Corps of French Geographical Engineers.*
(With a Plate.)
BaroMETRICAL measurements would be very limited and
almost useless if, as some philosophers seem to insinuate, they
were only practicable when we have corresponding and nearly
vertical observations to compare together. I am of opinion,
from my own observations, that this valuable mode of measure-
ment may be much further extended, and that it presents an
infinite number of applications, which must be useful to the
geologist, to the naturalist, to the soldier, and to engineers in
general.
It is of the more importance to point out all possible means of
levelling, because hitherto stational topography has hardly
entered into the class of operations by which engineers describe
the surface of the earth. We possess excellent plane topogra-
* Translated from the Eibliotheque Universelle, vii. 164, for March, 1818.
Z 2
356 M. Delcros’ Barometrical Measurement [Nov.
phical accounts; but these labours, though brought to great
perfection in this respect, are still absolutely defective as far as
pee is concerned. The method attempted of expressing
eights by different kinds of shading is exceedingly vague and.
unsatisfactory. Every person acquainted with the modern
improvements, and aware of the importance of a complete and
precise topography, would prefer the arid description of a
northern geometer to the sweet harmony imported trom Italy. I
appeal from my own judgment to that of all the civil and mili-
tary engineers ofall nations. Let not the caprice of fashion and
the necessity of yielding to its dictates be alleged. To eall in
the assistance of painting to that class to whom topographical
charts are useless, is to attempt a geographical description of
parlours and boudoirs. It is as if we wished to transform the
mathematical precision of the Mecanique celeste into familar
conversations on the world.
The present time may be considered as favourable for the
improvement of topography. All nations are eager to introduce
into it the rigorous methods which are adapted to it. Warcould
form only engineers skilled in giving a rapid and picturesque,
but vague idea of the country which they were called upon to
describe. The leisure of peace permits us to demand a superior
degree of perfection. Engineers formed in the first schools of
Europe promise us what we have long desired. They are quali-
fied to fulfil our expectations. Let us not offer them the seduc-
ing picture of romance—let us be as ngid and as sage in
geography as we are in literature. We possess engineers who
are excellent in planimetry. Nothing can exceed the perfection
with which they exhibit the horizontal projections of countries ;
but another step still remains, which cannot be difficult for men
of such skill. Let us take care neither to retard nor to stop this
progressive motion, or to convert it into a’retrograde motion by
allegations of superannuated authorities. In the sciences, as in
the arts, let us never look behind us, except to admire the
progress which has been made, and of which we should rather be
the emulators than the servile imitators. I have no hesitation to
say that a true topographical schocl, founded on the complete
study of the surface of the earth, is still wanting in France and in
Europe. When it is formed, and when the complete science of
geology is taught in it, we shall then possess engineers capable
of describing and expressing every thing.
Among the improvements proposed for obtaining a good
geometrical description of the topography of places adapted for
public service, a complete levelling has been proposed, expressed
upon charts by the projections of the equidistant curves of the
level resultmg from the common section of the surface of the
ground, witha series of horizontal planes equidistant in a vertical
direction. This method is perfect. It is absolutely necessary
in order to arrive at the end proposed. Vertical topography is
one of the most important bases of every geographical descrip-
1818.] of the Profile of Mount Jura. 357
tion ; without it we can form no idea of the form and relations
of the ground. I consider this kind of information as the most
important of all. In fact, it is often of less consequence to the
engineer to be acquainted with the horizontal distance of an
object exactly, than to know its relative height. In all cases,
both civil and military, the relation of height is of primary
importance. A topography which leaves it out has only the
appearance of being useful.
The difficulty, the tediousness, and the inaccuracy of geome-
trical levellings may be objected; and I admit these objections.
Great geodesical levellings formed by the sole practicable
system, reciprocal zenith distances taken at different times, are
influenced by the anomalies of terrestrial refraction. A good
system of previous observations in which all the effects of pertur-
bations were combined, would furnish, it is true, a complete
suite of circumstantial co-efficients. But this great undertaking
is still to commence. Topographical levellings, executed by
means of angular data, besides their dependance on horizontal
distances and vertical bases, are extremely tedious and delicate.
They suppose an exact planimetry; they are affected by the
inappreciable irregularities of refraction. The series of absolute
heights thus determined is subject to accumulations of errors,
which the probable compensation of opposite errors can but ill
obviate. In countries exposed to violent changes, the difficulties,
and with them the ezrors, augment. Very steep declivities often
are beyond the limits of the instruments: the horizontal bases,
which are less exact in such countries, combined within accurate
angles, affect the levels with a degree of uncertainty which may
be very considerable.
The difficulties and imperfections which I have pointed out
belong to the most favourable case of all, when the engineer is
furnished with proper instruments to give the zenith distances ;
and when he possesses a very exact planimetry of the country
to be levelled; and when several absolute heights are already
accurately determined ; when he has sufficient leisure, the means
of marking out the different signals, &c. &c. But how far is the
solitary geologist, naturalist, or engineer, from this advantageous
position! Horizontal bases, the means of measuring them, a
sufficient number of known points, exact instruments, and time
itself, that fugitive element which presses so much upon the
travelling geologist, are here all wanting. Whole ages would
not be sufficient to enable an engineer to obtain the complete
vertical topography of a country of moderate extent; and yet
the geologist and the geographer are often under the necessity
of levelling with rapidity, and of determining in a few days the
whole profiles of systems of mountains, of which he rarely pos-
sesses a tolerable chart, and never an exact planimetry.
Without the assistance of the barometer such a situation
would be desperate. This instrument, so simple, so precious,
358 M. Delcros’ Barometrical Measurement [Nov.
so little known, so little valued, so despised, may be employed
with advantage, and may come in place of the impracticable
system of geometrical levelling.
The idea of employing the barometer for vertical topography
is neither mine nor is it new. All the philosophers who have
become practically acquainted with this instrument have recom-
mended it. De Saussure and De Luc may be considered as
its creators; after them, Ramond, Humboldt, Pictet, Prony,
De Buch, &e, have either applied it or brought it to the greatest
degree of perfection. It is with the greatest diffidence that I
offer my observations after the immortal labours of these illus-
trious geologists.
Notwithstanding the encouraging example of all these philo-
sophers, the use of the barometer is still very much neglected.
Mathematicians despise it without attempting to become practi-
cally acquainted with it. Naturalists, more disposed to adopt it,
are afraid of venturing to apply it, and generally neglect it.
I do not flatter myself that I shall prevail upon these different
classes of observers to make use of the barometer ; I shall merely
add a few facts to the mass already collected.
Barometrical measurements may be obtained by two methods.
1. By asystem of corresponding observations made at the same
time. 2. By suites of successive observations not made at the
same time, but sufficiently near to answer the same purpose as if
they were contemporary.
The first of these methods supposes corresponding observa-
tions made at points previously agreed upon, and with barometers
compared with each other. But it is often difficult to obtain
these two conditions, and they keep the observer absolutely
dependant on his base. In extensive measurements he is soon
too far from the corresponding points to be able to reckon on the
exactness of the comparisons.
The second method may be of the greatest utility, in conse-
quence of its perfect independence, of its rapidity, and I may
say, likewise, in consequence of its exactness. This method,
like the former, supposes us to set out from a known base ; but
when once set out, we become independent of it. Let us figure
to ourselves the astonishing rapidity with which we can measure
the height of whcle regions and of lines of immense extent, and
we shail be able to form a conception of this method. The want
of correspondence of successive observations will no doubt be
objected to me. I cannot deny this inconvenience; but it
becomes very small if the observer abstains from observing when
obviously disturbing causes intervene; and if he multiplies his
observations so as to have them at intervals of half an hour from
each cther, then his errors will be smaller than if he were
obliged to employ corresponding observations at the horizontal
distance of 20, 30, or 50 leagues.
We can almost always combine these two methods, which will
ee ee
1818.] of the Profile of Mount Jura. 359
thus throw light upon and verify each other. This I sometimes
did formerly ; but I propose to do it more frequently hereafter,
now that I know the advantages of it. I have already given to
the public a partial measurement of Mount Ventoux. If mean at
present to give the profile of Mount Jura on the line from
Geneva to Lons-le-Saunier and the chateau Mirebel. A rapid
examination of it which I made in 1813, to ascertain some geode-
sical points, furnished me with an opportunity for determining
it. i regret that the little time I had at my disposal, and the
length of time which an cbservation of Fortin’s barometer
requires, did not allow me to make so many as I could have
wished. But notwithstanding this great inconvenience, the
reader will be astonished at the results which I have obtained
from successive observations often made at an interval of several
hours, and from other corresponding ones made at Paris, Geneva,
and Strasburg.
The table which I give in the first place exhibits in four
columns the principal successive observations, and the corre-
sponding ones which I could collect. It will be observed how
far my successive heights are from each other.*
Having interrupted the suite of my observations, I divide
them into three series, which I place in the order in which they
were made,
I shall not state here the particular calculations which I have
made of all the combinations of the observations in this table.
I shall be satisfied with arranging together the results which they
have furnished in a:single table, the first columns of which give
‘the simple heights of the stations by successive observations. In
the four succeeding columns I shall give the absolute heights of
these same stations determined from a comparison of the corre-
sponding observations made at Geneva, Strasburg, and Paris.
The last four columns, in which I shall collect the differences of
these results, will show the errors to which we are exposed in
unfavourable circumstances, and will enable us to foretell their
limits in more advantageous cases; that is to say, when the
corresponding observations are made at places less remote, and
when the successive observations are nearer each other in respect
to time and horizontal space.
* Wesuppress this table, because its great bulk would render the printing of it
rather embarrassing, We shall confine ourselves to the results of the observations.
—(Note by the editors of the Bibliotheque Universelle.)
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1818.] of the Profile of Mount Jura. say
the time when it ceased to be visible, it ae ne under the
form of a very obtuse pyramid upon the top of an apparent hill, ©
produced by the effect of refraction upon the plain, the refracted
points of which, in consequence of their distance, exhibiting to
me an inclined plane imitating upon the horizon the projection
of a hill. The poplar, whose enormous pyramid rose to the
height of 28 metres, appeared to me then reduced to a spherical
mass of three or four metres in height ; and if we recollect that
the contour of the line to which [ referred these appearances was
itself elevated by refraction in proportion to its distance, we
shall have an idea of the differences of terrestrial refraction at
different times of the day. I give here four figures representing
in the opening of the objective of my telescope the profile of the
trench and the different aspects of the signal and poplar in its
neighbourhood at the four principal epochs. (Plate LXX XVI.)
I conceive, from a great deal of experience, that the refractions
in the same season are nearly horary. Hence it would be of
great importance for geodesy to determine the horary values of
the coefficient. We might then hope to obtain good vertical
measurements by means of zenith distances. Till this great and
useful undertaking be accomplished, I can recommend to geo-
graphers a method which has succeeded with myself, and
which I regret that I did not think of sooner. It is founded on
the coincidence of hours. To determine the difference in the
height oftwo points, I observe thei reciprocally at the same hours,
though on different days. This expedient is not rigorously exact;
but | am persuaded that it has the advantage of eliminating, in
the same season, the principal error. It may be employed by a
single observer, as is often necessary in practice. By adopting
this method, so simple and so easy, which neither requires more
means nor more calculations, and which spares the time that
would be uselessly wasted on taking repeated zenith distances,
I believe with confidence that we should be able to reduce the
limits of disagreement to small fractions of a metre. I intend to
employ this metliod in the new geodesical operations with which
I am going to be charged; and I expect from it the most com-
plete success.
It has been proposed to determine the circumstantial coeffi-
cient by observing the zenith distance of a point whose height
is already known ; but this supposes the refraction to remain
constant during the intervals of the observations ; and, likewise,
that the trajectories of the rays coming from all the points of the
horizon are similar curves, modified in proportion to the dis-
tances ; but all these suppositions are gratuitous, and contrary
both to theory and experment. The method which I propose
has not the same inconvenience. The luminous ray passing
through the same space undergoes very probably the same modi-
' fications, especially if the barometrical pressures and the temper-
366 M. Delcros’ Barometrical Measurement [Nov.
atures are nearly the same, which we may ascertain for our
greater satisfaction.
A similar undertaking remains to be executed for the formula
for barometrical measurement. This last is affected likewise by
horary influences. All the observers, and particularly M. Ra~
mond in his celebrated and useful researches, have pointed out
this effect. It is the coefficient for noon which has been gene-
rally adopted and applied to all the hours of the day ; for noon
would limit the barometrical method too much. We must
employ the whole day if we wish to obtain series of points,
profiles, &c. Let me then request zealous observers employed
m elevated situations, geodesically connected, to collect the
data requisite for the solution of this interesting problem. Iam:
at this moment employed in calculating a series of 112 corre-
sponding observations made with great care at two points, the,
‘diflerence of whose heights has been trigonometrically deter-
mined. These observations were made at intervals of two hours,
from eight o’clock in the morning till six in the evening. If 1
succeed in discovering any pretty constant law, I shall commu-
nicate it to the public. But it ought not to be concealed that
the determination of such laws ought to be the result of an
immense number of observations collected in all seasons, made
in all hours, and varied in many different places, and with
different horizontal and vertical distances.
Paris, Feb. 15, 1818, DeE.cRos.
—
Appendix by the Editors of the Bibliotheque Universelle.
It may be worth while to quote, in support of our correspond-
ent’s ideas, the opinion of a celebrated philosopher on the
comparison of the measurements of heights by the two methods
of trigonometry and the barometer. This opinion is found in
the memoirs of M.le B. Ramond “ Surle Nivellement Barome-
trique des Monts Dores et des Monts Domes,” presented to the
Academy of Sciences in 1815, in which he announces having
determined the absolute height of about 400 remarkable points
in the most interesting part of the department of the Puy-de-
Dome, and indeed of the whole of France. For this region,
which comruiirontiige: the mean parallel of our hemisphere, is
likewise the portion of the realm where the mountains are most
elevated, andthe levels the most different and best characterized,
by the very different nature of the beds, mostly volcanic, but
belonging to epochs separated by very long intervals of time.
He has examined how the inhabitants, spontaneous vegetation,
and culture, are distributed on a vertical scale of 1900 metres,
between the 45th and 46th degrees of latitude. Called as he has
been more than once in the series of his operations to compare
his barometrical data with the geodesical results obtained by
:
!
1818.] of the Profile of Mount Jura. 367
zenith distances, observed by skilful mathematicians furnished
with repeating circles, he finds sometimes discordance between
the two methods, and great probability in favour of the first ;
sometimes agreement; and in that case a prodigious advantage
in facility and dispatch on the side of the barometer ; “ and the
accuracy of the trigonometrical method,” he observes, “ has
likewise its bounds. When we compare together the total and
partial measures which it has furnished us, we are forced to
acknowledge that none can be depended on nearer than one or
two metres. This uncertainty indeed is but small; but that
which attends barometrical measurements is not greater ; and if
we employ separately the different series which have concurred
to the determination of the mean angle, these exhibit disagree-
ments which far exceed the limits within which the errors of the
barometer are confined.”
“« The imperfection of the two methods comes from a common
source ; and the two instruments are equally defective when the
disposition of the atmospherical strata is such that the gradual
decrement of heat and humidity is altered or inverted. But this
disorder exhibiting itself to the trigonometrical instruments by
anomalies in the refraction, appears to exercise on the results an
imcomparably greater effect than when it alters the ratio of the
pressures indicated by the two corresponding barometers. In
this last case, a small number of observations is sufficient to
compensate for the errors ; but in the first case a very consider-
able number are requisite: and M. Broussaud and myself have
convinced ourselves that barometrical measurements taken with
care are preferable to trigonometrical measurements themselves,
whenever these last do not repose on reciprocal and very nume-
rous observations, made with excellent instruments and by ver
skilful persons, with all the conveniences and all the time
requisite for such operations.”
———
Explanation of the Profile of Jura in Plate LXXXVI. Places
denoted by the Letters.
a, Geneva.
6, Gex.
c, Mount Colombier.
d, La Faucille.
e, Valley of Mijoux.
Jf, Culminating point ; vallon tourbeaux.
g, Sept-Moncel.
' A, Highest point of the road.
2, St. Claude.
k, Bienne (river).
4, Chateau de Prax.
m, Roche d’Antre ; signal.
n, Moyrans.
368 Dr. Burney on some Atmospheric Phenomena [Nov.
o, Road near Citernon.
p, Bridge de la Pyle on the Ain.
q, Highest part of the road.
r, Orgelet.
s, Mount Tourget.
t, Highest point of the road.
u, Ditto.
v, Lons-le-Saunier.
ax, Plateau Calcaire.
y, Chateau Mirebel (signal).
A B, Syphon barometer, constructed at Berne, in 1811, by
Noseda, a pupil of Paul, of Geneva; and employed in 1811] and
1812 in the barometrical measurements executed by M. Delcros
in Alsace and in Switzerland.
GD, Profile of the tube without the mounting.
ArTIcLE VI.
Remarkable Atmospheric Phenomena and their Effects.
By Dr. William Burney.
Gosport Observatory, Sept. 24, 1818.
Since the commencement of autumn, considerable changes
have taken place in the atmosphere from a dry to a humid and
electric state, and the temperature has consequently been very
much diminished.
On the lst inst. we had a storm of rain, hail, thunder, and
lightning ; the latter continued very strong and vivid from two
till half-past four, a.m. while the thunder proceeded in a north-
west direction. On the 5th, 1°33 inch of rain fell, which is as
much as had fallen here during the preceding 16 weeks.
16th.—At a quarter before eight, p.m. a large lunar iris
appeared on an extensive Nimbus to the west, the harvest moon
being in the east, nearly full, and about 10° above the horizon ;
in 15 seconds after, it was well formed by refraction and the
reflection of the lunar rays through the falling drops of rain, the
moon. was eclipsed by a dark passing cloud, and the phenomenon
disappeared instantaneously. There was no time to measure it,
but the semicircle appeared nearly as large as the solar rainbow
under-mentioned.
2ist and 23rd.—We had strong equinoctial gales rising from
the south and south-west soon after sun-rise, and dying away at
sun-set.
A solar halo appeared on light vesicular vapour on the Ist, 6th,
14th, and 22nd, anda lunar halo in the evening of the 17th;
three of them were 44°, and two 45° in horizontal diameter,
their perpendicular diameters being somewhat greater; and
1818.] and their Effects. 369
they were all followed by. rain, in some instances in less than
four hours after disappearing.
On the 23d, from 40’ till 55’ after five, p.m., a double solar
rainbow appeared to the east, when the sun was within two or
three degrees of the western horizon, and measured as follows :
Diameter of the exterior semicircle. .......... 84° 30’ 00”
Distance of the interior from the exterior bow at 8 22 30
the north side. .... Meine THe SRR. 5 Basins
Distance of ditto from ditto at the south side.. 8 22 30
Greatest diameter of the exterior semicircle.... 101 15 00
This measurement of the rainbow is as wide as it can be within
9’, according to the most accurate calculation ; it was of longer
duration, and the finest in colours that I ever remember to have
seen; and the sun was so favourably situated as to make it the
largest in extent.
Sept. 25.—Fine coloured parhelia appeared this morning at
intervals from 50 minutes past seven till five mimutes past eight
o’clock, on an attenuated Cirrostratus cloud from the soutiward.
At eight, the sun’s altitude from the horizon was 19° 4’ 40”, and
each parhelion was 23° 30’ distant from, and parallel with, the
real sun, making their altitudes equal with the luminary, and
the halo in which they were situated, and which was very con-
spicuous, 47° in horizontal diameter. Each parhelion disap-
peared three times, and their formation on re-appearing was
more simple than that of the parhelia which I attempted to
describe in page 235 of the last number of the Annads: the
colours, however, were similar, but the mock-suns smaller, viz.
a little larger than the apparent size of the sun’s disc.
State of the Wind, Clouds, and Instruments, at Eight 0’ Clock.—
Wind, duesouth. Attenuated Cirrostratus, gradually increasing
in extent and density, through which the sun shone faintly,
and some Cirrus in the zenith. Height of the barometer 29-60
inches, and of the thermometer 55°. De Luc’s whalebone hy-
grometer 75°, there having been a copious deposition of dew
upon this instrument till after sun-rise. These, as well as the
last parhelia, were followed by a sinking barometer; the sky
was overcast by two, p.m. and rain came on at four.
26.—-About eight minutes before eight, a.m. three coloured
parhelia appeared on a thin Crrrostratus that was passing very
slowly in a north-west direction from this place ; the sun’s altitude
at the same time being 18° above the horizon, and the halo, in
which the parhelia were situated, 45° 10’ in horizontal diameter
to the outside of the colours.
The two parhelia parallel with the sun, were each 22° 35’, and
the upper parhelion nearly 23° distant from the centre of his disc ;
the latter was formed by the intersection of part of another halo
at the top of the perfect one, and the parhelion at the point of
Vou. XII, N° V. 2 om
370 Dr. Burney on some Atmospheric Phenomena [Nov.
this intersection was the largest and the most resplendent in
prismatic colours. The three parhelia thus situated in the upper
aha of the perfect halo, formed, with the sun, two right
angles.
ithe state of the instruments was nearly the same as at eight
o’clock yesterday morning, and very heavy showers of rain fell
during the afternoon. Hence it may be concluded that both
solar and lunar halos are certain signs of a humid atmosphere
and of approaching rain.
The rains this month, amounting to upwards of four inches,
- have penetrated the dusty surface to a good depth, and have '
had beneficial effects on the vegetable tribes : the loamy meadows
too, which three weeks ago were completely scorched by the
hot sunshine, so that scarcely a blade of grass could be seen,
are now overspread with a lively verdure, having the appearance
of spring.
—ire—
Remarks on the Weather that preceded and followed two other
Mock-Suns, seen at Gosport Observatory.
Oct. 2.—At eight, p.m. a very brilliant meteor fell through
space of about 25° ; it was of the apparent size of Jupiter, towards
which planet it proceeded in its descent from the zenith, witha
astonishing velocity. :
5.—At one, a. m. several loud claps of thunder, and lightning,
accompanied by heavy rain, and strong gusts of wind at inter-
vals, driving the clouds upon each other.
6.—At seven, p.m. a small whitish meteor, which emerged
from behind a Czrrostratus cloud to the S.W.: at 10, the sky
cleared up, by achange of wind from W. to N.W.
7.—A copious dew (which, with a temperature of 40°, pene-
trated through the glass windows), that had been deposited on the
grass before sun-rise, was converted into fine hoar-frost for the first
time this autumn. In a few minutes after sun-rise, a Stratus
arose in the adjoining meadows, perhaps from the exhalation of
the heavy dew. When the sun had ascended a few degrees, a
parhelion appeared in the eastern point of the compass, 23°
distant from, and parallel with, his disc; a broad streak of
Cirrostratus crossed the sun at the time, and reached near the
mock-sun, which was adorned with the usual prismatic colours.
Barometer 29°75 inches, thermometer 45°, hygrometer 80°, and
the wind due north. A sunny day, with ramified, linear, and
plumose Carvz from the N.W., forming into extended arcs as
they passed off by the force of an upper current from that quar-
ter, it being calm below; these Czr7z were succeeded by fleecy
and dusky Cumuii, some of them very lofty ; also Cwnulostratus,
which, on coming to the zenith, passed to a Nimbus, and a short
shower followed: after 10, p.m. the sky became apparently
clear.
4
—
1818] and their Effects. 371
8.—Heavy dew and hoar-frost as the preceding morning: at
six, a.m.a dense Cirrostratus formed a fog-bank on Portsdown-
hill, about four miles distant ; and on its arriving here at eight
o’clock, the hygrometer, which before stood at 75°, went to 80°,
notwithstanding a brisk northerly wind : a clear atmosphere the
remainder of the morning. P.M. Fleecy and dusky Cumult,
which, being to the westward, at sun-set passed through orange,
dark blue, lake, and crimson tints, while the eastern sky exhi-
bited a rose colour ; the arched part of it was about 35° in height,
with a purple base : this magnificent appearance of the evening
Crepusculum, which remained in view an hour after sun-set, was
evidently produced by reflection from haze descending rapidly
in that quarter, the dew having fallen here copiously soon after-
wards: an apparent clear sky through the night.
9.—Very heavy dew and hoar-frost as the preceding morning ;
also a dense Stratus resting on the ground, and large Cirri and
Cirrocumuli descending into the lower atmosphere. At 10
minutes before eight, a.m. another parhelion appeared 23° 30’ to
the east of, and parallel with, the sun, on an attenuated Cirro-
stratus that was passing slowly in an easterly direction: the
south end of this modifcation did not extend more than 10°
beyond the real sun, nor was there any solar halo to be seen;
but a faint one appeared at noon, Hence a parhelion with its
natural colours may appear without a solar halo when a cloud is
thus situated between the sun and the observer, or when there
isnot enough vesicular vapour on either side of the sun to create
a mock-sun ; and on the other hand, a solar halo 45°, 46°, or 47°
in diameter may frequently be seen in a vaporous atmosphere
without a parhelion, or parhedia.
Faint sunshine through attenuated and undulated Cirrostratus,
and some distant Cumuli near the horizon till five, p.m. when
the wind veered from N.W. to 8.W., and the night turned
out wet.
The two subsequent days and nights were very wet, mostly
drizzlmg, till the evening of the latter day (the 11th), when a
strong gale with heavy rain came on from the S.W. and closed
this change of weather; and the barometer is now rising to its
former level.
. Errata.
In the middle of p. 235, the article a before beautifully
coloured parhelia is superfluous ; and in the second line below,
for equidistant from, read equidistant 23° 30’ from.
Biz
©
372 Dr. Philip on Stimulants and Sedatives. [Nov-
ArticLe VII.
On Stimulants and Sedatives. By Dr. Wilson Philip:
(To Dr. Thomson.)
DEAR SIR, Worcester, Sept. 28, 1818.
In compliance with your request, I trouble you with a few
observations in illustration of the following remarks in the 254th
page of the second edition of my Inquiry into the Laws of the
Vital Functions ; namely, “A moderate application of every
agent appears to act asa stimulus ; and excessive application of
it as a sedative. The quantities which act as stimulus and
sedative bear no particular proportion to each other, but in differ-
ent agents exist in every possible proportion.”
It appears on the most cursory view of'the phenomena of life
that they depend on a capacity of action in living parts and the
operation of agents capable of exciting them. Thus the heart
possesses the power of contraction, but it soon becomes inactive
1f the blood is withdrawn. The degree of excitement produced
is proportioned to the force and continuance of the exciting
cause and degree of excitability possessed by the part acted on.
By the action of the stimulus, the excitability is always impaired,
and by its continued action at length exhausted. Thus excite-
ment continues, unless the agent is withdrawn, till the part is so
far deprived of its excitability that it will no longer obey the
same degree of the same agent. To produce further excitement
a more powerful agent must be applied, or the excitability of the.
part acted on must be increased. ~
The excitability is, within certain limits, increased by the
abstraction of agents. Thus, for example, our sensibility, one
species of excitability, is exhausted by the various agents which
affect us during the day ; and we find by degrees that the same
agents no longer excite us. If more powerful agents are not
applied, we soon fall into a state of insensibility, sleep, during
which the operation of the usual agents being withdrawn, we
again become sensible to these agents.
Such are the more evident laws of excitability ; and it would
be easy, I think, to prove that they are the laws which regulate
the cerebral system in a state of health. But it has been main-
tained that the same laws regulate the excitability of every part
of the animal. To this position a very obvious objection occurs.
When the eye becomes wearied with seeing, the ear with
hearing, &c. they cease to be excited; their excitability is thus
allowed to accumulate, and they are again fitted for their func-
tions : they are not concerned in the preservation of life. An
animal may be in perfect vigour, as far as relates to the powers
on which his existence depends, although he ‘neither sees nor
hears. The vital powers remaining in sleep restore vigour to the
Le ek
1818.] Dr. Philip on Stimulants and Sedatives. 373
exhausted organs of sense ; but were the vital organs themselves
subject to similar exhaustion, what during such intervals would
preserve the life of the animal? and by what powers would the
vigour of these organs be restored ?
It has béen said, indeed, that the diastole of the heart arises
from the stimulus of the blood exhausting its excitability in the
systole which is restored to it during the interval that elapses
between its contraction and the occurrence of that degree of
distention which again excites it. But a very simple experiment
shows the fallacy of this opinion.
If the heart is exhausted by the stimulus of the blood, and
recovers its excitability during the absence of such a quantity of
this fluid as is capable of exciting it, it ought not to recover its
excitability if it is prevented from expelling any part of the blood
which has excited it ; for we have seen that the continued appli-
' cation of the same stimulus which has produced exhaustion
cannot again excite the exhausted part, as no renewal of
excitability can take place while the agent which exhausted it is
still applied. The retina will never recover its powers under the
impression of the same degree of light which exhausted it. We
cannot recover from fatigue while the cause of our fatigue still
operates. But the alternate contractions and relaxations of the
heart still take place, as I have ascertained by repeated experi-
ment, although a ligature be thrown around the aorta, im conse-
quence of which, the heart remains uniformly gorged with blood.
The result of this experiment is not influenced by previously
destroying the sensibility of the animal by a blow on the occiput.
If we sprinkle salt on a muscle, it does not occasion perma-
nent contraction followed by exhaustion, but a constant alter-
nation of contraction and relaxation, although the salt is never
removed. The state of the muscle, however, in the relaxations
which intervened between the contracttons is evidently very
different from that in which it is left when the salt can no longer
excite any contraction in it.
The foregoing facts seem to prove that the nervous and mus-
cular excitability obey different laws. While the effect of uniform
stimuli acting on the former is permanent excitement, followed
by exhaustion, the habit of the muscular fibre under the influence
of uniform stimuli is to act by intervals. This is probably the
cause why moderate excitement seems not to exhaust the mus-
cular fibre, while the nervous fibre suffers proportional exhaustion
from every degree of excitement.
Two circumstances appear to be capable of occasionally
counteracting this habit and producing in the muscular fibre
permanent contraction, a peculiarly strong stimulus and the
influence of the will, It is only, however, occasionally that the
most peru stimuli have this effect; and it is only for a
limited time that the will can produce it. After a certain time,
the natural tendency of the muscle to alternate contraction apd
374 Dr. Philip on Stimulants and Sedatives. [Nov.
relaxation prevails, and the limb which we wish to keep steady
begins to tremble. f
There is another species of debility of the living fibre of a very
different nature from the exhaustion we have been considering,
which appears to bear no relation to any previous excitement; but
to be the direct effect’ of agents ; for while some agents increase,
others lessen, the action of this solid. The former have been
-called stimulants, the latter sedatives.
It has been maintained, indeed, that as exhaustion is the
effect of moderate excitement, the species of debility we are now
considering is always the consequence of excessive excitement ;
and, therefore, that, like exhaustion, the sedative effect is never
the direct effect of the agent. And this opinion seems at first
view to be countenanced by the fact that stimuli act as sedatives.
when applied in excess. Thus a moderate quantity of distilled
‘spirits received into the stomach produces excitement, which,
within certain limits, is greater in proportion to the quantity
taken; but if a verylarge quantity be suddenly received into the
stomach, it produces no degree of excitement, but immediate
debility, or even death.
It is surely a strained explanation of the latter effects, how-
ever, to suppose them the consequence of excessive excitement,
no symptom of which appears. The supposed existence of this
excitement rests wholly on the preconceived opinion, that
exhaustion, in consequence of previous excitement, is the only
debility which can arise from the operation of agents on the
living fibre. It has, therefore, been maintained, that however
imperceptible the excitement produced by large quantities of
distilled spirits for example, we must suppose that their first
effect is excitement, and their debilitating effect, consequently,
only secondary. And so much has this idea laid hold of the
minds of many, that im an account of the above Inquiry, lately
published in a journal of great respectability, my opinion of the
nature of inflammation is opposed on the ground that the opera-
tion of agents in producing this disease must, in the first instance,
be stimulant ; and the debility of the vessels, which it is admitted
exists in inflamed parts, the consequence of previous excitement ;
and this is maintained without questioning the accuracy of my
experiments, from which it appears, that none of this previous
excitement could be perceived with the aid of powerful micro-
scopes. Now I may surely be allowed to maintain that where
no imcreased action can be perceived, none should be supposed.
We must not substitute hypothesis for plain matier of fact.
But if this argument, which is of all the most conclusive,
were out of the question, there is another, which, as far as I can
judge, would be unanswerable, to which even the supporters of
the hypothesis m question must listen. It must be admitted,
even by them, that if the tendency of different agents to produce
debility arises from the degree of excitement occasioned by their
1818] Dr. Philip on Stimulants and Sedatives. 375
first impression on the living solid, those best calculated to pro-
duce excitement should be found capable of the greatest sedative
effect. But this isso far from being true, that we find that the
agents which produce the greatest degree of this effect are the
worst stimuli. Tobacco, for example, which is one of the most:
owerful sedatives, cannot, by any management, be made to
produce the degree of excitement which arises from opium or
distilled spirits.
The sedative, like the stimulant effect, may be communicated
to the muscular through the nervous system. When tobacco is
applied to any considerable part either of the brain or spinal
marrow, as I have ascertained by repeated experiment, the heart
soon begins to act more languidly ; but this languor is preceded
by little, if any, increased action, unless the tobacco be applied
in a very diluted state ; in which case, it produces comparatively
little languor, and the excitement is much less than that pro-
duced by opium, which is followed by no sensible languor.
If we disregard preconceived opinions and fix our attention
on facts alone, we shall, as far as I am capable of judging,
arrive at the following conclusions. Every agent capable of
_ affecting the living solid acts both as a stimulus and sedative
according to the degree in which it is applied. Applied within
certain limits, it is a stimulus ; and in proportion as it stimulates,
it exhausts the excitability, this being equally true of the inter-
rupted excitement which stimuli produce in the muscular, as of
the permanent excitement which they produce in the nervous
system. Applied beyond these limits, agents no longer produce
excitement followed by proportional exhaustion, but direct
exhaustion arising from the operation of the agent, and wholly
unconnected with previous excitement, the stimulant and seda-
tive powers existing in no particular proportion to each other,
but in different agents in every possible proportion. I have just
had occasion to mention the comparative effects of tobacco and
opium in the heart. Thus the stimulant power of distilled spirits
is great, its sedative power small. {t must be used in very great
quantity to produce the sedative effect ; while a small quantity
a fignalis produces this effect, and its stimulant power is very
8 Le }
hese observations apply to agents affecting the mind as well
as the body. Grief and fear possess great sedative power ; they
act as stimulants only when they are present in a comparatively
small degree. Joy and anger, on the other hand, are powerful
stimuli, and only act as sedatives when in excess. There is no
exception, I believe, to the law we are considermg. There is
no agent which may not be made to produce a stimulant effect
by applying it in very small quantity, and none which does not
act as a sedative when applied in excess. 1 remain, dear Sir,
our faithful humble servant,
A. P. W. Pur.
»
376 Dr. Thomson on the — [Nov,
ArricLe VIII.
On the Annual Fall of Rain at Glasgow.
By Thomas Thomson, M.D. F.R.S.
Iris a general opinion that the quantity of rain which fails at
Glasgow is greater than the fall at Edinburgh ; but this opinion
does not seem founded upon any well-authenticated documents.
It is probable that it rains more frequently at Glasgow than at
Edinburgh; at, least this is the general opinion, and is not
denied by the inhabitants of Glasgow themselves. But to judge
from the registers kept at Glasgow and near Edinburgh, the
quantity of ram which falls in the neighbourhood of the former
city is rather less than what falls in the neighbourhood of the
latter. We are in possession, indeed, of no regular table of the
weather at Edinburgh; but a rain gauge has been long kept by
the Duke of Buccleugh at Dalkeith Palace, within six miles of
Edinburgh ;.and the annual depth of rain which falls at this
place is regularly published. Now this is uniformly greater than
the fall of rain at Glasgow. Indeed when the situation of Glas-
ow is considered, one would expect less rain at it than at
dinburgh. It is nearly 20 miles inland from the west coast ;
and is, therefore, beyond the immediate influence of the Atlantic,
which renders some parts of the north-west of England so
rainy ; while its distance from the east coast, and the high land
between it and Edinburgh, screen it from those violent rains
when the east wind blows, which are so common in Ediaburgh.
The distance of the hills from Glasgow is further than from
Edinburgh ; and it is in some degree screened by high grounds
both on the east and the west.
The city of Glasgow lies in north latitude 55° 51’ 32”,* and in
iongitude 4° 16’ west from Greenwich. The surface of the
Clyde at Glasgow at low water is probably elevated about 15 feet
above the surface of the sea at Greenock ; for the tide rises only
a few feet at the new bridge, and it proceeds but a very little
beyond Ruthergien bridge, which is scarcely the eastern boun-
dary of this populous city. The College gate is elevated 60 feet
above the Clyde; and the Macfarlane observatory, situated m the
College garden, must be very nearly et the same elevation. A
rain guage, constructed by Crichton, was placed upon the top of
this observatory in the year 1801; and a regular register has
been kept of the rain ever since by the Professor of Astronomy.
This rain gauge is elevated about 20 feet above the surface of
the garden, or 80 feet above the Clyde. Itis situated on a plain,
at some distance from any houses, and not overlooked by any
trees. The situation, therefore, with the exception of its height
above the river, is as favourable for accurate observations as can
be. Itdeserves to be mentioned that the rain guage at Dalkeith
* Edinburgh is in north latitude 55° 56’42”. It is, therefore, 5’ 10” further
north than Glasgow, which is very nearly six miles.
1818.j Annual Fall of Rain at Glasgow. 377
Palace, and the one at Sir Thomas Brisbane’s, at Largs, upon
the west coast, are all exactly similar, and were all made by
Crichton; so that they can be accurately compared with each
other. Dalkeith Palace stands, I conceive, at a greater height
above the river Esk than the Macfarlane observatory does above
the Clyde. The following table exhibits the fall of rain at Glas-
gow for the last 17 years. It was kindly drawn up at my
request by Dr. Couper, Professor of Astronomy.
Register of Rain at the Macfarlane Observatory.
1801. | 1802. | 1803. | 1804. | 1805, | 1806. | 1807. | 1808. | 1809,
Inches.
Bee 1°627 | 0°426 | 3°881 | 1°483 | 2-329 | 0-908 | 1-246 | 1-435
Feb.... 1°645 | 1°544 | 0-545 | 1°617 | 1°579 | 0°959 | 0-778 | 2-Sv0
March.. 0°927 | 0:752 | 2°310 | 2°130 | 0-272 | 0-288 | 0-082 | 0°:360
April 1°450 | 1-051 | 0°791 | 0°630 | 0°683 | 1-085 | 1:5z5 ! U-£86
May... 0°606 | 1°286 | 2°406 | 0°885 | 2°085 | 2:430 | 157i | 2-379
June... 1-500 | 1:229 | 1°150 | 1-023 | 0-737 | 0-995 | 1°814 | 2-479
July... 3°802 | 0°800 | 1:587 | 1°414 | 2-693 | 3-205 | 3-118 | 2-245
August. 2:000 | 2:11] | 3°676 | 1°778 | 2°869 | 3415 | 5597 | 5-283
Sept....| 2°015 | 1-200 | 1-900 7T1 | 2°030 | 1-497 | 2°746 | O'616 | 2-925
0:
Oct... .| 2°912 | 2°851 | 0:595 | 2°527 | 0-015 | 2°254 | 3-644 | 2°171 | 1-442
Noy,...}| 0°993 | 0°679 | 1°540 | 1-937 | 0°309 | 3:°506 | 1°553 | 2°135 | 0-925
Dec.. ..| 1°347 | 1-470 | 1234 | 0-701 | 2-468 | 3.358 | 1°016 | 1°342 | 3-153
<|— we
Total. . 19°757 [14-468' 122-282 |15-782 |23-862 [29-244 121-795 |25-189
1s10. | 1811. | isiz. | 1813. | 1814. | 1815. | iste. | 1817. | 1818,
em) ae - — -
Inches, . r
Jan....| 1°743 | 1-723 | 1°352 | 1-242 | 0:032 | 1°135 | 1-342 | 2624 | 2-594
Feb....| 1°283 | 2°T35 | 1°424 | 2°746 | 0°826 | 2°312 | 1°514.) 3°103 | 2-163
March, .| 1°687 | 1°254 | 1°865 | 1:342 | 0-702 | 2-457 | 1:126 | 0 627 | 1-952
April..| 0°659 | 2°054 | 0°842 | 0-216 | 1-654 | 0°925 | 1-243 | 0-072 | 1-420
May ...| 0°510 | 2°783 | 1°443 | 2-133 | 0°625 | 2:104 | 1-715 | 1-930 }. 1-212
June...} 1°145 | 1°982 | 1°802 | 0°794 | 0-127 | 1-246 | 1°584 | 2-312 | 0-904
July ...| 3°724 | 1°635 | 1°531 | 2°342 | 2°478 | 1°531 | 4°312 | 1-773 | 4:963
August.| 2°874 | 3°545 | 2°166 | 1-307 | 2°397 | 2°354 | 2°146 | 2:854 | 0-310
Sept....| 0°724 | 1°273 | 2°342 | 1°563 | 0°384 | 2:275 | 3-214 | 0-629
Oct. ...} 1°176 | 2°854 | 5:345 | 2-385 | 3°145 | 2-402 | 2-446 | 0°892
Nov....} 3°374 | 3-252 | 2-452 | 1-362 | 2°976 | 1-823 | 1-014 | 2°546
Dec. ...} 2°534 | 2°T11 | 0-246 | 0-936 | 4°176 | 1:780 | 2°143 | 3°058
Total. .!21°433 |27-801 22°810 |18°868 {19-522 |22°344 |23-799
oe
22°420
The following table of the fall of rain at Corbeth, 12 miles
north-west from Glasgow, near the Campsie hills, and at the
height of 4663 feet above the level of the Clyde at Glasgow,
will give the reader an idea of the great increase of rain as we
advance nearer the west coast and the mountains. [t was kept
by Mr. Guthrie, of Corbeth; and the rain gauge is precisely the
same as that used at the observatory of Glasgow.
UBTB 6s... dee ses 41°393 inches,
MANE: (ssid aus athe Mie @ ret
1817 eeeeoeeeeen ed 44-965
378 " Analyses of Books. [Noy.
ARTICLE IX.
ANALYSES OF Books.
Transactions of the Royal Society of Edinburgh, Vol. VIII.
Part IL. 1818...)
This part contains the following papers :
I. On the Effects of Compression and Dilatation in altering the
Polarizing Structure of Doubly Refracting Crystals. By David
Brewster, LL.D. F.R.S. Lond. and Edin.—Dr. Brewster shows
that when pressure is applied to a thin plate of calcareous spar
bounded by planes perpendicular to the axis of double refraction
(the shorter diagonal of the crystal), the circular rings of colour
formerly observed change their shape. A similar effect is pro-
duced upon quartz, and indeed upon all doubly refracting crystals,
whether negative or positive. ‘He shows very ingeniously that
this alteration is not owing to a modification of the original
force, but to the creation of a new force. Hence it is easy to
determine d priori the effect of compression or dilatation upon
doubly refracting crystals. When positive crystals are com-
pressed parallel to the axis of the crystal, the tints rise; when
the axis of compression is perpendicular to the axis of the crystal
the tints descend. When the same crystals are dilated, the
opposite effect takes place. If the crystals be negative, compres-
sion in the direction of the axis makes the tints descend ; perpen-
dicular to the axis, it makes them rise. By dilatation, vice versa.
Il. Experiments on Muriatic Acid Gas, with Observations on
tts Chemical Constitution, and on some other Subjects of Che-
mical Theory. By John Murray, M.D. F.R.S.E. This paper
will be printed in a future number of the Avnals.
Lil. Haperiments on the Relation between Muriatic Acid and
Chlorine; to which is subjoined the Deseription of a new Instru-
ment for the Analysis of Gases by Explosion. By Andrew Ure,
M.D. Professor of the Andersonian Institution, and Member of
the Geological Society.
lt has been demonstrated by decisive experiments, and is
universally admitted, that when chlorine and hydrogen gases are
mixed together in equal volumes, and an electrical spark is passed
through the mixture, these two gases disappear, and there is
found in place of them a quantity of dry muriatic acid exactly
equal in volume to the two gases before the combustion. Two
explanations of this fact have been advanced. Gay-Lussac and
Thenard, who, as far as I know, were the first chemists that
established the fact by rigid’ experiments, explained it in this
way. Chlorine gas is a compound of one volume of muriatic
acid and half a volume of oxygen condensed into one volume.
The volume of hydrogen combies during the combustion with
the half volume of oxygen, and forms water. This water unites
with the muriatic acid, which is incapable of existing without it
Se ee
1818. Edinburgh Transactions, Vol. VIII. Part I. 379
in the gaseous state, and of course of being separated from it
without depriving this acid of its gaseous state; and according
to their calculations, the water which thus constitutes an essen-
tial part of muriatic acid amounts to about 4th of the weight of
the compound. According to this explanation, chlorine is a
compound of one atom of oxygen and a certain unknown sub-
stance which has never yet been obtained ina separate state. If
we add an atom of hydrogen to this compound, it unites with the
atom of oxygen, is converted into water, and this water combining
with the unknown basis, converts it into muriatic acid gas. Sir
Humphry Davy explained the fact in another and a much sim-
pler manner. According to him, chlorine is a simple (that is to
say, an undecompounded) body. Anatom of it has the property
of combining by combustion with an atom of hydrogen, aud of
forming muriatic acid. Gay-Lussac and Thenard have adopted
this explanation, and. abandoned their own. Indeed they sug-
gested it in their original publication ; and Gay-Lussac informs
us that he had embraced it from the first, and that he had always
from that time taught it in his lectures.
According to the first of these explanations muriatic acid is a
compound of 1th water and sths of an unknown substance,
which constitutes the acid of the muriates: according to the
second it is a compound of chlorine and hydrogen.
Dr. Murray, of Edinburgh, is almost the only person in this
country who has supported the first or o/d opmion. A controversy
took place several years ago in Nicholson’s Journal, between
him and Dr. John Davy, on this subject; the former supporting
the old, the latter the new opinion. This controversy was
carried on by both with much ability, and led to the discovery of a
variety of new and interesting facts ; but it terminated as almost
all controversies do: both combatants retained the original
opinions with which they had set out, and both of them boasted
of having gained a complete victory, and of having established
his own opinions by the most satisfactory arguments.
It occurred to Dr. Murray that muriate of ammonia might be
employed to furnish an evidence on the one side or the other
which should be decisive. According to the old view of the
subject muriatic acid contains 1th of its weight of water: when
it unites to ammonia this water ceases to be necessary to its
constitution, and may, therefore, be obtained in a separate state.
Suppose we mix equal volumes of dry muriatic acid and ammo-
niacal gases, they combine and constitute sal-ammoniac. Now
a volume of ammonia approaches to half the weight of a volume
of muriatic acid ; therefore, dry sal-ammoniac, formed by the
union of the gases, must contain about the 6th of its weight of
water ; therefore, 100 grains of sal-ammoniac made in this way,
if the old theory be true, must contain nearly 17 grains of water.
Dr. Murray formed sal-ammoniac by uniting the gases; he ex-
posed it to heat, and he obtained, in every case, a sensible
quantity of water: this result, in his opimion, decided the con-
380 Analyses of Books. [Nov.
troversy in his favour. As sal-ammoniac when prepared from
the dry gases always exinbits traces of water, it follows, he
conceives, that this water must have existed in combination with
the muriatic acid ; therefore, &c.
But this mode of reasoning did not satisfy his adversaries.
The quantity of water thus evolved they said was small, and it
became less andless according to the care taken to have moisture
more completely excluded. They ascribed the water which made
its appearance to the aqueous vapour which always exists in gaseous
bodies, and from which, perhaps, it is impossible to free them.
Dr. Ure is one of those persons who seems to have thought
well of the opinion which Dr. Murray defended, but not of the
experiments by which he supported it. The object of the present
paper is to bring forward unequivocal evidence of the existence
of water as a constituent of sal-ammoniac and of muriatic acid,
and to infer from this that the old opinion is the true one.
He sublimed sal-ammoniac very slowly through clean metallic
filings (silver, copper, and iron) previously heated to redness in
a glass tube. In every experiment, when properly conducted,
there was a deposition of liquid in the part of the tube beyond
the metals : this liquid was water of ammonia. The water which
appears in this case he concludes must have previously existed
in the sal-ammoniac ; for as that salt contams no oxygen, it is
plain that no watce could have been formed by the decomposi-
tion of the sali.. The old opinion, therefore, that muriatic acid
vas contains water as an essential constituent, he considers as
established by his experiments. These experiments appear to
have been made with much care, and I have no doubt that the
results are as Dr. Ure states them. I do not, however, see any
reason for considering these experiments as decisive of the
question, or as more favourable to the old opinion than the new.
A short explanation will enable the reader to perceive the
reasons on which this opinion is founded.
1. Muriatic acid seems capable of combining with most of the
salifiable bases while in a liquid state, and of forming compounds
to which the term muriates may be applied. Some of these
compounds may be even exhibited in a solid state without de-
composition. Now the salifiable bases (with an exception of
two) contain oxygen, and muriatic acid contains hydrogen. Of
course the constituents of water exist in all the muriates. Now
whenever a muriate is subjected to a red heat it undergoes de-
composition: the hydrogen and oxygen unite, and fly off in the
state of water ; while the chlorine combines with the reduced sali-
fiable base, and forms a chloride. Thus when muriate of barytes
is exposed to a red heat it is converted into chloride of barium,
muriate of manganese into chloride of manganese, and so on.
2. When muriatic acid comes in contact with a salifiable base
at a red heat, the very same double decomposition takes place ;
the chlorine unites to the reduced salifiable base, and forms a
chloride ; while the oxgyen of the one unites with the hydrogen
1818.] Edinburgh Transactions, Vol. VIII. Part ITI. 381
of the other, and flies off in the state of water. Accordingly it
has been ascertained by experiment, that when muriatic acid
gas is made to pass through red hot lime, barytes, strontian,
&ce. chloride of calcium, barium, strontium, &c. is formed, and a
considerable eee of water is evolved. :
3. In Dr. Ure’s experiments it is obvious that the sal-ammo-
niac was partly decomposed ; for the liquid obtained was water of
ammonia ; therefore, the experiments are quite the same as if
-muriatic acid gas had been passed slowly through a glass tube
heated to redness.
4. But a glass tube contains several salifiable bases ; namely,
oxide of lead, oxide of manganese, soda, &c. These will be
partially converted into chlorides at a red heat, and of course
water will be formed. Sir H. Davy has ascertained by experi-
ment that this actually happens: he obtained water by passing
muriatic acid gas through red hot glass tubes. Here then we
see the source of the water in Dr. Ure’s experiments, without
being under the necessity of considering it as previously existing
in sal-ammoniac.
The same explanation will apply to the water which made its
appearance when Dr. Ure substituted muriatic acid gas for sal-
ammoniac in his experiments. Into that part of the paper,
therefore, I need not enter.
I may here notice an illustration which Dr. Ure employs in his
aper, and which is to be found likewise in Dr. Murray’s paper,
which will be printed in a future number of the Annals ;—-it is that
sulphuric acid cannot exist without water. Now this is a mis-
take. I can procure sulphuric acid free from water, with great
- ease, and I exhibited it last winter in that state to the Chemical
Class in the University of Glasgow. The mode of obtaining
anhydrous sulphurie acid, and the account of its properties in
that state, will be found in the Fifth Edition of my System of
Chemistry, vol. i. p. 105.
Dr. Ure’s eudiometer for exploding combustible
gases is ingenious. It will be understood from the
figure in the margin. It consists of a glass tube,
sealed at one end and open at the other, bent into a
syphon shape, with the two legs of equal length.
The shut end is graduated, and furnished with me-
tallic wires in the usual way. The mixture of gas to
be exploded is put into the graduated side ; a portion
of mercury is allowed to remain in the bend of the syphon,
filling it for example to a. Between a and the open mouth the
tube is filled with common air. When the gas is to be exploded,
cover the open mouth of the syphon with the finger, and pass
an electric spark. The common air acts as a recoil spring, and
prevents the fracture of the tube.
IV. On the Laws which regulate the Distribution of the po-
larixing Force in Plates, Tubes, and Cylinders of Glass that have
received the polarizing Structure. By Dr. Brewster.—The
382 Analyses of Books. [Nov.
author’s observations and experiments are of so miscellaneous a
nature, that we could scarcely make them intelligible to our
readers by abridgment: we must, therefore, refer them to the
paper itself. It is terminated by the description of an instru-
ment for measuring the elasticity of bodies, to which Dr. Brew-
ster has given the name of teznometer.
V. Remarks illustrative ¢ the Scope and Influence of the
philosophical Writings of Lord Bacon. By Maévey Napier,
Esq. F.R.S. Lond. and Edin. and F.A.S. Edin. Bacon is uni-
versally admitted to have first pointed out the importance of
induction in advancing the sciences, and to have laid down the
laws according to which inductive philosophy is to be cultivated.
For many years this method has been generally adopted, and
the progress of the sciences has accordingly been vast, and is
still continuing., It has been generally admitted that the com-
mencement of this great career was entirely owing to Bacon,
and that he of consequence may be considered as in some
measure the author of all the discoveries in science that have
been made since his time. But there are some individuals who
are of a contrary opinion. According to them, Bacon’s writings
had little effect, and indeed cozitinued almost unknown till the
sciences had made very considerable progress. The object of
this very entertaining and judicious paper is to show that this
latter opinion is erroneous; that Bacon’s writings produced a
ereat and immediate effect both in Britain and on the Continent ;
that both Newton and Boyle regulated themselves by his views,
and that they led to the establishment of the Royal Society, to
which the physical sciences lie under such obligation for their
progress. These important points are established by an in-
duction of particulars, which produces conviction, and which
furnishes a good example of that Baconian logic, the value of
which it is our author’s object to establish.
It is not easy for us at present to estimate the exact effects of
the Novum Organum ; but that they must have been great, is, I
think, undoubtedly true. In the present advanced state of the
sciences, however, I conceive that the young philosopher may
employ his time better than in studying the rules of Bacon’s
logic. The inductive method is much more easily acquired by
example than by precept. Let him select the best examples of
true inductive reasoning which are to be found, Newton’s
Optics and Principia for example, and let him study these so
thoroughly as to imbibe their true spirit. He will be better
qualified to advance the progress of any of the sciences than by
a life-time devoted to the perusal of Bacon. Among the men
of science in this country who have devoted considerable talents
and much industry to the prosecution of scientific investiga-
tions with very little benefit either to themselves or others, were
I to be asked to point out who have been most conspicuous, I
should without hesitation select those who have professed the~.
greatest admiration of the Baconian logic.
1818.] Edinburgh Transactions, Vol. VIII. Part IT. 383
VI. Sketch of the Geology of the Environs of Nice. By Tho.
Allan, Esq. F.R.S. Edin.
From this paper it appears that the country in the immediate
neighbourhood of Nice is composed of limestone. Mr. Allan
distinguishes two different formations, which he calls first and
second limestone : the first he suspects to be transition, and the
second to be floetz, but he did not verify his suspicions by sa-
tisfactory evidence. The first limestone has a brown colour, a
compact texture, a conchoidal fracture, and, in general, shows
no appearance of crystallization, though sometimes it does. It
contais petrefactions, shells of different species, as cornu-am-
monis, pecten, and corraloids. Flint also occurs in it in nodules,
and seems sometimes to be in regular beds, as in chalk. Several
varieties of this limestone are described. The second limestone, °
it would appear from the map which accompanies the paper,
lies chiefly in the valleys skirting the different rivulets. It has
the aspect, according to Mr. Allan, of having been twmbled down
from above the first limestone ; it lies in the most irregular
state, and is distinguished by those contortions and involutions
which have been so often described by the Huttonians with so
much delight. Had they examined the loose sand on the north
side of Edinburgh, they would have seen as many contortions in
it as in the rocks of St. Abbshead themselves.
The second limestone is composed of strata varying very much
in thickness from a few inches to several feet ; its colour varies
from bluish to brownish grey ; sometimes it is hard and close
grained, with a splintery fracture; sometimes its texture is
earthy, and it gives an argillaceous smell. It contains a pro-
fusion of shells. :
Besides these two formations, there is a vast deposite of al-
luvial gravel on the west side of Nice, and in other places in the
neighbourhood. This gravel consists of fragments of primitive
rocks, and contains mixed with it a vast quantity of shells,
many of them the very same species that still exist in the Me-
diterranean.
The paper concludes with a catalogue of the shells found by
Mr. Allan near Nice : they amount to 225 species. This cata-
logue is drawn up by Capt. Brown, who ascertained the names
of the species ; and there are 33 species which he considers as
new. Of these he has given figures.
VU. On certain Impressions of Cold transmitted from the
higher Atmosphere, with the Descripiion of an Instrument adapted
to measure them. By John Leslie, F.R.S.E. and Professor of
Mathematics in the University of Edinburgh.
Mr. Leslie is the philosopher to whom we are indebted for almost
all our knowledge of the radiation of heat. He himself, how-
ever, has never admitted the truth of the opinion that heat ra-
diates. According to him heat is nothing else than light fixed
in bodies ; it never can leaye a body at all without losing the
character of heat, and assuming that of light. What others
384 Analyses of Books. [Nov
consider as radiation, he affirms to be nothing more than pulses
of the air, similar to the undulations by which sound is propa-
gated; these undulations may be either of heat or of cold, ac-
cording as they proceed from a heated or a cooled surface.
Accordingly, the amount of these pulses, or what is called the
radiation of heat, differs according to the gas through which
the pulsation takes place. In hydrogen gas it is much greater
than in air, and in a complete vacuum it would disappear alto-
gether. Nothing can be more ingenious than his views on this
subject, nor than the instrument which he has contrived for mea-
suring the pulses of cold emitted from a clear sky. But as,
after reading over his paper with some attention, I have not been
able to see clearly the evidence on which his opinions are
founded, I think that the best way to do justice both to Mr.
Leslie and to the readers of the Annals will be to print his paper.
It will appear, therefore, in an early number.
VIII. A Method of determining the Time with Accuracy,
from a Series of Altitudes of the Sun, taken on the same Side of
the Meridian. By Major-General Sir Thomas Brisbane, Knut.
F.R.S.E.
Sir Thomas Brisbane having been moving much about for a
number of years, was unable to carry with him large astrono-
mical instruments ; he was induced in consequence to try how
good results he could obtain from small instruments. His
success has been such as to induce him to recommend the
sextant as an instrument which would be much more employed
by astronomers if its value were known. In this paper he shows
his method of determining the time from a series of altitudes of
the sun on the same side of the meridian. This method he
recommends as fully as exact as the method by equal altitudes,
and as more exact than that method when a change of tempe-
rature has taken place in the interval between the forenoon and
afternoon observations. For the method itself we must refer to
the paper, as it could not be made intelligible without tran-
scribing the whole calculation.
IX. Observations on the Junction of the Fresh Water of Rivers
with the Salt Water of the Sea. By the Rey. John Fleming,
D.D. F.R.S. Edin. As the specific gravity of salt water is
greater than that of fresh, Dr. Fleming naturally conjectured
that when the tide begins to flow up the mouth of a river, the
salt water will occupy the bottom of the channel, and will be
covered by the fresh water which will occupy the surface. A
set of trials made on the waters of the Frith of Tay at different
times of the tide, fully confirmed the accuracy of his opinion.
Mr. Stevenson made similar observations on the waters of the
Don, but he found this not quite the case with the Thames.
From his trials on that river he was led to infer that the fresh
water moves backwards and forwards without any real flow into
the sea.
X. Memoir of the Life and Writings of the Hon. Alexander
1818.] Scientific Intelligence. 385
Fraxer Tytler, Lord Woodhouselee. By the Rev. Arch. Alison,
L.L.B. F.R.S. Lond. and Edin. We shall insert this very in-
teresting memoir in our next number.
ARTICLE X.
SCIENTIFIC INTELLIGENCE, AND NOTICES OF SUBJECTS
CONNECTED WITH SCIENCE.
I. Academy of Natural Sciences in Philadelphia.
A number of individuals in Philadelphia have for some years
been accustomed to meet at leisure hours for the purpose of
communicating to each other such facts and observations as
were calculated to promote the knowledge of the natural sciences
among themselves, and of extending it among their fellow
citizens. On April 25, 1817, they were by the legislature of
Pennsylvania incorporated into a society under the title of the
Academy of Natural Sciences of Philadelphia. They have made
some progress in the formation of a museum and a library; and
since the time of their incorporation, they have begun to publish
a journal in the octavo form. By Jan. 1, 1818, eight numbers
were published, making in all 218 pages. The first four num-
bers consist of a sheet each; the next three of two sheets; and
the eighth, which is the last number that I have yet seen, con-
sists of three sheets and 2 of a sheet ; but of it !2 sheets are
filled with the act of incorporation, the constitution of the society,
and a catalogue of the books and museum belonging to them.
This Academy cannot but greatly promote the advancement
of all the branches of natural history by making us better
acquainted than we have hitherto been with the natural produc-
tions of the vast continent of America. To give my readers
some idea of tthe subjects treated of in the Journal of this
Academy, | shall transcribe the contents of the numbers pub-
lished during the year 1817.
1. Description of six new Species of the Genus Firola,
observed by Messrs. Le Sueur and Peron in the Mediterranean
Sea in the Months of March and April, 1809. By C. A.
Le Sueur.
2. Account of a North American Quadruped, supposed to
belong to the Genus Ovis. By George Ord.
3. Description of seven Species of American Fresh Water
and Land Shells, not noticed in the Systems. By Thomas Say.
4. Descriptions of several new Species of North American
Insects.. By Thomas Say.
5. Observations on the Genus Eriogonum and the Natural
Order Polygonez of Jussieu, . By Thomas Nutall.
Vou. XII. N° V. 2B
386 Scientific Intelligence. {Nov.-
6. Notice of the late Dr. Waterhouse.
7. Characters of anew Genus, and Descriptions of three new
Species upon which it is formed; discovered in the Atlantic
Ocean, in the Months of March and April, 1816; lat. 22° 9”.
By C. A. Le Sueur.
8. Description of three new Species of the Genus Raja. By
C. A. Le Sueur.
9. Some Account of the Insect known by the Name of
Hessian Fly, and of a parasitic Insect that feeds on it. By
Thomas Say.
10. On a new Genus of the Crustacea, and the Species on
which it is established. By Thomas Say.
11. An Account of an American Species cf the Genus Tanta-
lus, or Ibis. By George Ord.
12. An Account of the Crustacea of the United States. By
Thomas Say.
13. A short Description of five (supposed) new Species of the
Genus Murena, discovered by Mr. Le Sueur in the Year 1816.
By C.A. Le Sueur.
14. Description of two new Species of the Genus Gadus. By
Mr. Le Sueur.
15. Description of a new Species of the Genus Cyprinus. By
Mr. Le Sueur.
16. An Account of an American Species of Tortoise, not
noticed in the Systems. By C. A. Le Sueur.
17. A new Genus of Fishes of the Order Abdominales, pro-
posed, under the Name of Catastomus ; and the Characters of
this Genus, with those of its Species, indicated. By C. A.
Le Seur.
18. An Account of two new Genera of Plants, and of a
Species of Tillea and Limosella, recently discovered on the
Banks of the Delaware, in the Vicinity of Philadelphia. By
Thomas Nutall.
19. Description of new Species of Land and Fresh Water
Shells of the United States. By Thomas Say.
20. Descriptions of four new Species, and two Varieties, of
the Genus Hydrargira. By C. A. Le Sueur.
21. Observations on the Geology of the West India Islands,
from Barbadoes to Santa Cruz, inclusive. By William Maclure-
22. Observations on several Species of the Genus Actinia ;
illustrated by Figures. By C. A. Le Sueur.
23. Description of Collinsia, a new Genus of Plants. By
Thomas Nutall.
24. Act of Incorporation; Constitution of the Society;
Library ; Donors to ditto ; Donations to Museum ; Apparatus.
Il. Common Magnesia Alba of the Shops.
Berzelius informs us that he has ascertained the common
magnesia alba of the shops to be a compound of three atoms of
1818.] Scientific Intelligence. 387°
carbonate of magnesia and one atom of hydrate of magnesia.—
(Ann. de Chim. et Phys. vii. 206.) Grotthuss has expressed a
suspicion that common magnesia may be a compound of carbo-
nate and hydrate of magnesia—(Schweigger’s Jour. xx. 276); a
suspicion which seems to have been verified by Berzelius about
the time that it was made ; for though Berzelius’s statement was
not published till some months after Grotthuss’s conjecture, there
is every probability that his experiments had been completed
before the publication of Grotthuss’s paper. Bucholz informs us
that magnesia alba exists in three different states of combination.
These observations of Berzelius. and Grotthuss may, perhaps,
apply correctly to the magnesia alba exposed for sale in the
apothecaries’ shops of Sweden and Germany. In these coun-
tries, the chemical medicines exposed to sale are subjected to an
annual examination. Hence it is natural to look for more
uniformity in their state than in this country where no such
examination takes place, and where every chemical manufac-
turer is left entirely to his own judgment. I have had occasion
to examine a good many specimens of magnesia alba purchased
in druggists’ shops, and I have found too great a diversity in its
composition to permit the conclusion that it is a chemical com-
pound. It seems rather to be a mechanical mixture of carbonate
of 2 oe caustic magnesia, and, perhaps, hydrated magnesia,
in different proportions. This no doubt would depend upon the
state of the alkali employed to throw it down from Epsom salt,
or muriate of magnesia ; for it is from these two salts that it is
usually procured. . I shall give, as an example, an analysis of a
magnesia alba, purchased in Glasgow, which I made last winter.
Carbonic acid. ...... 14:0 ...... 1 atom
Magnesia .......... SIs. irae « 4 atoms
Wittety ie wie ccalte nts 2 eK) ee es 5 atoms
Sulphate of lime. .... 6°6
100-0
III. Discovery of Hatiyne in the Island of Tyree.
M. Necker, of Geneva, some time ago, discovered haiiyne in
the primitive limestone of the island of Tyree. The following is
the account of the specimens which he observed, as stated by
him in a letter to Professor Jameson :—
Colour.—Sky blue, pure, and sometimes a little greenish.
Lustre.—Vitreous, shining.
Transparency.—Pellucid.
Fracture.—Vitreous.
Hardness.—Scratches glass.
Chemical Characters.—With the biow-pipe does not melt, but
loses its colour and becomes opaque.
2B2
388 Scientific Intelligence. [Nov.
By the acids it is dissolved; the quantity was too small to
ascertain whether it formed a jelly.
Occurs disseminated in grains not exceeding a line in diameter,
in nodules composed of feldspath, mica, and sahlite, which are
found in the limestone rocks on the sea shore, west of the farm
of Balapheitrich, near the quarry of primitive limestone in the
island of Tyree. The specimen of these nodules which I have
brought home with me from that spot being small, and the
haiiyne not abundant, and in very small grains, 1 was very
limited in my experiments upon this interesting substance here,
for the first time I believe, found elsewhere than m volcanic
rocks. I trust that by your exertions, and those of future tra-
vellers in the western islands, more will be known of this mmeral.
To promote such an. inquiry, you may, if you think it proper,
imsert this in some of your scientific journals. I think [ have
mentioned the place where I found it in a manner clear enough
to guide the mineralogist who may chance to visit the island of
Tyree. It is on the rocks near the high water mark, exactly
due west of the farm house of Balapheitrich, in round nodules
projecting from the surface of the limestone strata.
Believe me, my dear Sir, your obedient humble servant,
L. A. Necker, Prof.
IV. Tungstate of Lime.
This rare mineral, the nature of which was first ascertained
by Scheele, was some years ago subjected to a rigid analysis
by Berzelius. He found ita compound of
Tungstic acid ...... 80°417 ...... 100-00
Laman € 24:50 be ee 0-200) hiner eee
As it is aneutral salt, there can be no doubt that it is a com-
pound of one atom tungstic acid and one atom lime. Hence if ~
an atom of lime weigh 3°625, an atom of tungstic acid must
weigh 15.
Professor Bucholz and Mr. Rudolph Brandes, without being
aware of what had been done by Berzelius, have lately subjected
two varieties of this mineral to a very careful analysis. It is an
object of some consequence to compare the results which they
obtained with those of Berzelius, that we may see how far they
confirm his conclusions. I shall, therefore, state here the
composition of the two minerals according to their analyses.
The first variety had a yellowish white colour, and a specific
gravity of 6-076. It was from Schlackenwald. Its constituents
were
Tungstic acid. ..... SN mIREY
PRE Pobre a le\ssn tw wip tanita dO. oe
BE Matha ciclo tale in of nid DRA alin
—
1818.] Scientific Intelligence. 389
The second variety was from Zinnwald ; its colour was brown,
and its specific gravity 5-959. Its constituents were,
Punestic, acid .,.:5)05 =e == == RPE PP ESP Pe T
F apissparepareotaed: edelale Tail
Diana maleebdemaiae araalatal 4elelels BOGUL camoame we
; SR SSS SOR SSas 4 GEESE ee eeeee! 4 ot
= + eeene ease eee hae 4b
|e
|| tei + }
| segceeesauee sce! HH
|
} |
PASEYLINO GD LUNG) H
ma
: i
| Ce
|
I
1)
| t
| o¢
| oF
ysog JO pony) ns
LL iG D = if jaann
| pairs ier CODASEOG 5
—- - - -—— Bi |
Peer :
| | ; Be? Fi bred
mt
[8p 060L %
LAAT 2?
1818.] Mr. Holt’s Meteorological Journal. 431
man or of nature through which he passed, and which enabled
him to enjoy every present hour with thankfulness, and to look
forward to every future one with hope.
The records of this Society contain the histories of greater
men—of none, I believe, more virtuous, more amiable, or more
happy; and while the lives of these illustrious men (written by
men of kindred genius) will, I trust, long continue to inspire in
this place the spirit of philosophical ambition, I dare to hope,
that even the faint outline which | have now given of the
character of Lord Woodhouselee, may tend to cherish that moral
ambition which all men are called to indulge ; without which
learning is vain, and talents are dangerous, and to which rewards
of a nobler kind are assigned, than either the praise of men or
the splendours of literary fame.
Articie II.
Meteorological Observations made at and near Cork.
5
By Thomas Holt, Esq.
(With a Plate. LXXXVII.)
REMARKS,
24. Dull day; showery evening,
Beall. 25, 26, Dull, dry day.
1. Fine, bright day; breeze. 271, Foggy morning ; light showers; dull
2. Ditto, ditto, day ; showery evening.
3. Dry, cloudy day; gale. 28, Bright morning ; cloudy day, with
4, Ditto, ditto. showers,
5. Dull day ; showery from 12; rainy || £29. Showery day.
evening. 30. Ditto; rainy evening.
6. Windy and cloudy ; no rain, MAY.
7. Rain last night; rainy day, with : =
fresh breeze. 1, Brightday, ;
8. Rain, day aod night, with wind, 2. Showers of hail, with great wind
9. Showery morning; fine afternoon and heavy rain. :
and night. ; 3. Cloudy morning and day; rainy
10. Showery day. evening and night,
11, Heavy gale, with frost and snow, || 4 Bright, warm day.
last night ; fine day, 5. Ditto. ; : L
6. Showers of hail and rain, with
12. Bright, frosty night; clear day,
with wind, lightning and thunder,
13, Rainy night and morning; dry, || 7+ Sbowery day. se
cloudy day. 8. Bright day ; showery evening.
14. Bright day ; occasional light showers. 9, 10, 11, 12, 13. Clear days; occa-
15. Rainy night and morning ; fine day ; sional showers. ! ;
rainy evening. 14, Bright day; windy ; rainy evening.
16, Rainy morning ; showery day ; fine 15,16, Ditto; few light showers.
evening. IT, 18,195 20, 21, 22, 23, 24, 25, 26;
17. Bright day; occasional light showers. 27, 28, 29, 30, SI. Bright, warm
18, 19, 20, Ditto, ditto. days.
21. Showery morning; dull, dry day; JUNE.
showery evening, 1. Cloudy, dry day; breeze.
22. Rainy night and day. 2. Very heavy, dense clouds; dry,
23, Rainy night ; dull day; rainy even || 3, Light shower this morning; dry,
ing. cloudy day.
\
432
4. Foggy morning;
breeze.
5, 6. Bright days; breeze.
4. Bright, hot day.
8. Lightning and thunder, with heavy
rain, at lla. m. ; fine afterwards,
9,10. Bright days; breeze.
11, 12. Bright, hot days; breeze.
13. Cloudy day ; cool breeze.
4. Ditto; breeze, with rainy evening.
15, Showers Jast night; cloudy day.
16. Showery day ; fine evening.
17, Bright day; breeze.
bright day;
Meteorological Observations made at Montreal.
[Dec.
18. Shower at 10, a.m.; bright day ;
cold wind.
19, 20, 21, 22. Fine days; cold breeze
and cold nights, with occasional
showers,
23. Bright day; breeze.
24, 25. Ditto, ditto,
26. Showery night and morning ; cloudy,
dry day.
27, 28. Bright day; breeze,
29. Bright, hot day.
30. Bright morning; very hot; cloudy
and cool afternoon.
RAIN,
1818. Inches, 1818, Inches. 1818, Inches.
April 1 May 1 June | 0-007
2 2 0°228 2
3 3 0°108 3
4 . 4 4
5] =: 0-450 5 5
6 6 0-150 6
a 0°504 7 0-180 7
& 0-684 8 0-050 8 0°396
9 0-048 9 9
10 10) 10
iH 0:072 11 ll
12 12 12
13 0-210 13 0°510 13
14 0-018 14 0-336 14 0:006
15 0-099 15 15 0045
16 0-516 16 0-036 16 0015
17 0-051 17 17 0-042
18 0:009 18 18 0°156
19 19) 19 O14)
20 20 20
21 21 Qt 0:015
22 0:882 22 22 0:144
23 1°032 23 23
24 0-010 24 24
25 25 25
26 0-090 26 26 0-042
27 27 27
28 0-408 28 28
29 0:054 29 29
30 0-018 30 30
31
5155 1°598 1-009
Articte III.
Meteorological Observations made at Montreal.
Tue following meteorological observations made at Montreal,
during the winter of 1816 and 1817, are much at the service of
the editors of the Annals of Philosophy. It is regretted that
the register is so imperfect, the state of the barometer not being
noted, and the thermometer frequently neglected ; yet it 1s pre-
1818.] | Meteorological Observations made at Montreal. 433
sumed that an inspection of it viewed in comparison with the
subjoined tables, copied from diaries kept during the month of
January, 1817, in Halifax and Boston, may not be without inte-
rest to some of your meteorological readers.
—_ a
Journal of the Weather at Montreal.
Thermometer.
Wind, Remarks.
8 a.m. ]} 12n. I p-m.|10p.m.
Foggy; rain.
Gusts of wind; cloudy,
Dec.26 36° 409 379} Ago) +» SW
27 AO Ad 40 32 SSW
98 34 36 36 34 SW Ditto, ditto,
29 33 30 27 19 NW Snow and hail.
30 4 14 14 5 WNW Clear and dry,
31 24 38 36 38 SE Stormy.
1817,
Jan, 1) 34 40} 46] 41 SW Foggy.
2 29 30 36 25 SSW Clear and dry,
3 10 16 20 39 NE—SE Ditto; ice on the St. Law-
rence broken.
A Ag 40 39 26 | SE—SW Rain; hazy; change.
5 4 8 10 12 Ww Clear, dry day.
6 8 10 10 8 NE Two inches snow fell.
Ui 12 1g| 18} 12 ENE |Hazy,
8 12 22 20 18 NNW __ |Snow; cloudy.
9 22 32 30 30 SW Ditto.
10 28 30 31 26 N Ditto.
ll 7¢ 18 12. 3 Ditto Ditto.
12) —4 |—0]|— 3] —10 Ww Clear and dry winds,
13} —10 4\/—0/ —10 Ditto Ditto, river closed up oppo-
; site the town of Montreal.
14) 49h) 70 2 | 210 Ditto Ditto, ditto entirely frozen;
temp. a few miles up the
country at 8 a.m, 22° un-
der zero.
15} —14 |—2)—2]—2 NE Cloudy,
i6| — 1 14 14 10 Ditto Crossing commenced on the
ice of the river.
17 1] 20 27 20 Ditto Four inches snow.
18 20 20 20 2 SSW Clear,
19} —11 — 6/—6/—0 WNW _ [Ditto, with much wind.
20/; — 0 if ie ees N Clear.
2; — 3 8 10 1 W Ditto,
22; — 1 10 S| se WSW Ditto.
23) — 8 7 3 | = 0 Ditto Ditto.
24 13 20 19 24 Ditto Snow.
25 2) 26 24 18 SSW Cloudy.
26 8 8 Ditto Clear and dry.
QT 5 Il 10 | = 2 SSE Ditto.
28| —16 —8/;}-—-6;—8 WwW Ditto.
291 — 8 — 0 4} —6 WSW Ditto,
30} — 9 —6;-0/]-—6 Ditto Ditto.
31; —I1 —0O|-—6 Ww Ditto
Feb. 1} —13 5 6 6 N Change; snow.
2 1 13 Ditto Snow.
8} — 83 .13 10 7 Ditto Cloudy.
4) -—12 | — 6] — 8 | —20 Ww Clear and dry.
S/fluid in bulb} —11 | —12 | —20 Ditto Ditto temp. by a corre-
sponding thermometer in
the country at seven
434 Meteorological Observations made at Montreal. [D¥c.
Thermometer,_
Wind. Remarks.
o'clock, a,m. 31° under
zero.
Variable
129 Ditto | |Cloudy.
10 Ditto Snow.
N Cloudy.
SW Snow. :
Ww Fair and clear.
—4 NW Ditto.
falling SE Blowing, with clouds.
Ww Clear; temp. in country
30° under 0°,
—14 Ditto Ditto and fair,
SW Ditto.
WNW Ditto; cloudy.
NW Fair and bright,
36 | Variable |Hazy; foggy.
SW Ditto.
SE Dittosnow and rainshowers.
sw—sS Cumulus clouds; evening
rain.
Ww Clear.
NNE 4Snow storm.
SW Blowy, cloudy weather.
Ww Clear and serene.
NNW—NE |A snow storm.
N—NE_ |Cloudy; heavy winds.
N Ditto.
Ww Clear and fair,
SW Ditto.
SSE Cloudy ; showers.
S Ditto.
S—SE Ditto, with rain.
SW Ditto; clear.
SSE Ditto, ditto.
SW Regular thaw commences. .
Variable |Clear; cloudy.
NW—NE (Ditto; frost succeeds again.
N Ditto; clouds.
NE Ditto, ditto.
NNE Weather clear and fair,
N Ditto.
Ditto Ditto.
NE Snow.
SE—SW Ditto and rain.
NNW Hazy.
SW Ditto.
SSW Sudden changes.
SSE Cloudy.
Ditto Ditto. .
SE Cloudy, hazy weather.
Variable {Fair and clear.
N Snow.
S—SW |Ditto.
SW Ditto.
iS) Ditto.
SW Fair, clear weather.
s Ditto, ditto.
1818.] Meteorological Observations made at Montreal. 435
Diary of the Weather at Halifax, Jan. 1818.
Thermometer.
Date, {~—A SS Winds,
8 a.m. 4pm. |10 p.m. Average.
Jan, | 36° 38° 38° 31-32 WNW—WSW
2 36 38 27 33°6 Variable
3 23 27 24 246 NW—N
4 38 50 56 48:0 SW
5 34 32 14 26°6 Ditto and NW
6 9 20 21 16°6 NW
q 36 33 25 ales Variable
8 19 23 15 19°0 N—NNE
9 13 25 30 22°6 NW
10 34 36 34 346 Caln
1] 36 26 34 32-6 WSW
12 26 25 20 23°6 Ww
Is; > “10 15 10 11°6 WNW
14 10 14 2 8°6 NNW
15 2 15 5 13 Ditto
16 4 13 10 9-0 NNE
17 8 20 16 146 Ditto.
18 30 36 40 so3 SE
19 32 22 14 22°6 WSw
20 10 12 10 10°6 NNW
21 12 23 22 19-0 Ditto—W
22 22 20° 20 20°6 NbyE
23 22 29 23 24°6 Ditto
24 15 25 25 21°6 Variable
25 20 19 15 180 N
26 23 31 29 27°6 NW—NE
27 19 21 12 17°3 N
28 4 — 0 — 8 — 40 ' NW
299 —T7 5 1 — 25 : NNW
30 8 8 -—5 3°6 Ditto
31) —2 15 5 6:0 NW
GENERAL OBSERVATIONS.
Average of the month. Days.
Dull and heavy.....--ce0.+-+++- sistwalner attolaletatafetete alors bisteet wie
RRCLANN AMV AMG ctata lo ote e.c'sisialaains)= 0/a) cisle's's xie'e\e\e/naieidiesla'e *Sodclp ae!
Dull weather, with snow ...........-+20-sseeeese Sianistosis 1
STOW: 65 one cicitcvameccsoculesecbele sssceseceuseucs ccaccoes 3
Wind and rain; stormy ...-0csseeseeeceecres seccecccccsee 2
Panic and Clever. sina elute ain'al ofeblale waive hitiaic alee cieve ats o)a.si waren lee
31
ONCE DAE Sr SAS DIC ACETIC BOONE Sa COE Or: sie dicciawapciastelsl a
Above freezing....... Baihic/a'es otis osncaplelaine siulipslnnecescpie 5
ECMO «de en avinjei a b aialslhavattsiotals sfel'emiole cece cccns cesccsccece 25
31
Medium temperature for the month ,.....se...000.0++008> » 20?
AN PURE 5 So istaiglads «tele sbidopalsie aie esi gas since suravinia slo guineie(OG
MAONVEAC, Gawain tiaisiass a/adetaln a pleninaienidassisns.casiels coeoe — 16
which was at four o’clock, a, m, on the 29th.
Snow fell on the 8th, rain 18th, snow 25th, &c, &c, &e.
QE
436 Dr. Thomson’s Observations on the Weights of (Duc.
Diary of the Weather at Boston, Jan. 1818.
a
Thermometer.
Jan. 1} 31° 48°
A. 22 | 48
3| 28) 44
A, 55) 50
5} 26] 28
“6| 29) 42
7] 34) 44
.8} 32 29
9 32) 44
10| 40} 42
ll] 38) 32
12} 19} 22
13] 12) 24
4, 14; 20
15) AF | 28
16] 34) 28
17 18 | 27
18} -37 | 33
19) 12] 15
20" IT | 20
21; 20) 30
22 9 | 20
23 26
24; 32) 30
2 AT | 32
26, 27 | 30
27 I 6
28; — 1 7
29} — 2] 2
30 5|] 13
31 (fv |
Be
37
8 a.m. 2 p-m.|9 p.m.|Average.
39:3
Al'3
373
49-6
26°6
376
376
29°0
36°0
40°6
31:0
19-0
19-0
153
21-0
30°0
37:0
30°0
12°3
17:0
22°6
13°3
19°0
30°3
25°0
25°0
71°6
2°0
12-0
TO
150
Wind,
Ww—NW
Variable
SSW
NW brisk
SW
Variable
NE—NW
WwSW
SE—W
SW—WNW
WwW
Ditto
N
Variable
NE
Variable
WNW high
W by N gale
Variable
Ditto
Ww
SW—NW
NW
Ditto
SW
NW
SW
SSW
Weather.
Clear, dry day.
Ditto, cloudy evening.
Fog ; rain.
Rain.
Clear; cloudy.
Foggy 3 ditto.
Snow; cloudy.
Ditto; cloudy.
Clear; cloudy; rain.
Cloudy ; fog.
Snow ; clear.
Clear ; fair,
Day clear ; snow.
Ditto,
Clear ; cloudy.
Snow ; lightning,
Rain; thunder,
Fog; snow.
Clear.
Clear; snow.
Clouds ; clear.
Serene.
Ditto 5, snow.
Snow ; cloudy,
Clear; cloudy.
Ditto, ditto.
Fair and clear.
Ditto, ditto.
Ditto, ditto.
Ditto, ditto.
Ditto, ditto.
Articie IV.
Some Additional Observations on the Weights of the Atoms of
Chemical Bodies. By Thoraas Thomson, M.D. F.R.S.
(€ontinued from p. 350.)
I sHALL now proceed to give the weights of the atoms of the
compound combustibles, the acids, &c. as far as the present
state of our knowledge will enable us to go.
102 Water composed of......
103 Carbonic oxide. ........
104 Carbonic acid ...........
105 Chlorocarbonic oxide ....
106 ‘Cyanogen Tee. oS
Number of atoms.
Weight of
a particle.
ee di ee ee B26.
aoa io
EO we alge e ee
- Po lar. ea
ee a. SIE 00
Re A iri ag
1818.J the Atoms of Chemical Bodies. 437
Number of atoms. Ma ss
107 Olefiant gas 2 ..e. see De +L A sees 0875
108 Carburetted hydrogen. .... lec + 2h ..... . 1-000
169N@hloric. ethers J..t.:46.). 05 2.¢:+°2: h + Ivch’ 16-250
110 Hydrocarbonic oxide ...... 3.¢ 450 B00 + Joke 6875
TiBoracic'acidtt . sk ob A eae Lb. bivepc D oikidGhas 2°875
MTGE 6 vetslvs a Scns s Ss aL akeetars l.s -#allo fouctle R200
113 Hypophosphorousacid. .... lp + lo .... 2500
114 Phosphorous acid.......... Lp.+t 20.0000. 3°500
115 Phosphoric acid .......... LipeP id townie. 4-500
116 Protophosphurettedhydrogen 1] p + 2h ...... 1-750
117 Perphosphuretted hydrogen. 1 p + 1A ...... 1:625
118 Protochloride of phosphorus. 1 p + 1 ch...... 6:000
119 Perchloride of phosphorus.. 1 p + 2 ch...... 10-500
120 Phosphuret of carbon...... Lag. cecil te teeis)ciah . 2°250
121 Hyposulphurous acid*...... ls.+ Lo .-. 3000
122 Sulphurous acid .......... ls + 20 we 4-000
dZor Sulphuric acid). . steals oe Weisz ko derislncny 752000
124 Chloride of sulphur........ Bis. “Bist Tehe Jagd. 6°500
125 Sulphuretted hydrogen. .... L. sib iptes 2°125
126 Sulphuret of carbon. ...... Osi ctbellea to tagdude750
127 Sulphuret of phosphorus. .. 1 s + 1 p?...... 3500?
128 VArsenious acid s. 2.26. sis os 1 a. yl) Gis sccenth250
]2G: (Arsenic acid si. 0.0%. ats‘. .la+ 250 7:250
130 Choride of arsenic ........ ia. Ay l-behn se. 11-500
131 Sulphuret of arsenic. ...... Lg. EE2i9 Lies 8°750?
132 Oxide of tellurtum......... dé Saw so Asa - 5:000
- 133 Telluretted hydrogen ...... LE tlae T Aifoswseerve 125?
134 Protoxide of azote......... ba. 4.1 le Deak halle 760
135 Deutoxide of azote ........ Ay) lc et hy Omtocteucratett 3°750
136 Hyponitrous acid ......... Parr te PSs. Gk 4:750
IevNitrous acid 4 23.01... P guise 4io bios. cise 760
* This acid is formed when zinc or iron is dissolved in sulphur-
ous acid. The salt obtained used to be called a sulphuretted
sulphite. conceive that I was the first person who pointed it
out as a peculiar acid in the fifth edition of my System of Che-
mistry. Gay-Lussac assures us that he had recognized its
existence before me ; but I am not aware of any publication of
his in which the fact was mentioned previous to the appearance
of my work. The composition of hyposulphurous acid is easily
deduced from the action of sulphurous acid on zinc or iron. One
half of the oxygen in the acid must go to the oxidizement of
the zinc or the iron. Of course the acid which unites with these
oxides must be composed of sulphur united with one half as
much oxygen as exists in sulphurous acid, that is to say, the
acid must be a compound of | atom one + | atom oxygen.
438. Dr. Thomson’s Observations on the Weights of [Dec.
f Number of atoms. Te
138 Nitric acid. ........ bebe la 7A obiohaan ts eo
139 Chloride of azote......... ot he estes eal Roser 19°750
140 Sulphuret of potassium. .... lp + 1s ...... 7000
141 Sulphuret of sodium. :..... 1, so§-ch Siicaitiow 5-000
142 Protosulphuret ofiron...... 1a + 1s) ...... 5°500
143 Persulphuret ofiron....... 17 +25 .«.. 7°500
144 Sulphuret of cobalt........ 1 Gok pdgsadswiiclee 5°625
145 Sulphuret of zinc.......... 1. ge + bluse der 6°125
146 Protosulphuret of bismuth.. 1 6 + 1s ...... 10°875
147 Persulphuret of bismuth... 1b + 2s ...... 12875
148 Protosulphuret of lead..... 12 + 1s ...... 15°000
149 Persulphuret of lead....... 12 + 2s dived 7000
150 Protosulphuret of tin.....<. 1 f + 1s ...... 9°375
151 Persulphuret of tin...... cow ad ases Pree li lars v5!
152 Sulphuret of copper. ...... 1, ch Gbakisvicdeen 10-000
153 Protosulphuret of mercury.. 1 m+ 1s ...... 27-000
154 Persulphuret of mercury. .. l m+ 25 ...... 29:000
155 Sulphuret of silver. ........ I ‘st: Asc hy ss Serie 15:750
156 Sulphuret of gold. ........ l.g +1 8 beskemschlt250
157 Sulphuret of palladium. .... lp + 1s ...... 9-000
Th6 Oxalic acid.\a.i.. ses: Oh.+.:2 €:+°3 0 2x 4-500
159 Formic acid ........ LA+ 2.6 +130): 4-625
160 Mellitic acid........ Lave ) 4c Sle 6°125
161 Succinic acid. ...... 2h.t+ 4c¢c+ 30 6-250
162 Acetic acid. ........ 3h+ 4c430 6°375
163 Citricacid. .......,.34 + 4c¢+4 40 7°375
164 Tartaric acid. ..6..5 34.4 ,4¢ 4+. 5.0) S04 8376
165 Gallic acid. ..i.0..% 3: hod. (6. cats te) sha 7:875
166 \ Fannin. \.).i66. 23 sie oR 3. Bod-.. G. citen4 oy saapanerehe
167 Saclactic acid. ...... Shek. 6c 498 -au1) egakel2b
168 Benzoic acid........ 6 Bo + 15.ci4) Sian ager 00
+ These numbers are the results of the analyses of Berzelius,
with the exception of oxalic acid. Berzelius states the amount
of the hydrogen in this acid at +,th ofan atom. It being obvious
that such a combination cannot exist, I have left out the hydrogen
till the point can be more accurately determined.
Itis scarcely necessary to remark that the mere knowledge of
the number of atoms of which a vegetable body is composed
cannot lead to an accurate idea of its cénstitution. The proba-
bility.is that these atoms do not unite altogether to form the
vegetable body in question; but that they enter in the first
place into binary or ternary combinations, and that these primary
compounds, by uniting with each other, form the vegetable sub-
stance in question. Thus we may conceive oxalic acid to be a
compound of one atom of carbonic oxide with one atom of cat-
1818.] the Atoms of Chemical Bodies. 439
Number of atoms. saa
169 Muriatic acid...........6. LA + 1 ch...... 4625
1707 Chilorie acid’ es F are GS Gh oe oe ANS 9-500
171 Protoxide of chlorine ...... Peep Td Aue 5*500
172 Deutoxide of chlorine...... Melee: BGG MBO Gray
173 Hydriodic acid ........... Ll ho CPAP Ee
174 Iodic acid. ...... ae PAE ve FQ OP 20-625
175 Chloriodic acid. .......+4. la + 2 ch? 24-625?
176 Hydroeyanic acid. ....... SM cy er dure a 3°375
Wy be: 00) Co) Rae 2 olefiant gas + 1 water ...... 2°875
178 Sulphuric ether. 4 olefiant gas + 1 water? ..... 4625?
bonic acid. It is even possible that 12 of these compound atoms
may unite with one atom of hydrogen, which would constitute
the oxalic acid of Berzelius. On that supposition the symbol
for oxalic acid would be 12 (le + 10) + (le +20))4+ 1h.
To give another illustration, we may suppose tartaric acid to be
a compound of | atom carburetted hydron + 1 atom-water +
1 atom carbonic acid + 2 atoms carbonic oxide; for these
binary compounds would exhaust the atoms of which tartaric
acid is composed.
1 atom carburetted hydrogen. .. 24 + 1c +00
MEAL OMMEWALEIZ, vyeusers th ocneken ee el
TOs) Starch. ssa geek py LO. Crater Se Oy cd ginkees 17-750
194 Gelatin.; .....« 44+ 1l5¢c4+4 60+ 24... 22-500
195. Albumiens «02 13,70, 17 co Geo): Granule
196, Fibrin,.....6.« L4;h 7m 18 .c.- 50 + 3 dup .ena0o
As we are ignorant of the weight of the last 20 bodies which
are capable of uniting with a given weight of any other com-
pound, it is obvious that we have no means of determining the
weight of an integrant particle of them. The numbers in the
table represent the weights of the smallest number of atoms
which agree with the analysis of each. If these analyses
approach the truth, it is obvious that an integrant particle of
each of these bodies must be either the number given in the
table, or some multiple of that number, as two, three, four times
the number. These analyses may be of some service in direct-
ing the attention of chemists towards the kind of binary com-
pound of the union of which these bodies may be supposed to
consist. But it would be a mistake to consider the second
column of the table as representing the real constitution of the
vegetable and animal bodies subjected to analysis.
I shall now proceed to give an example or two of the consti-
tution of the salts. It would be unnecessary to give complete
tables of all the salts, because their composition may be readily
conceived by considering each neutral salt as a combination of
one atom acid and one atom base.
Sulphates.
Atoms of acid, base, Weight ofa
and water. particle.*
197 Sulphate of ammonia.... 1 s + 1 a@ + Swater 7125
198 Sulphate of potash ...... iS" GP ayer -+ 11-000
* The water is not included in this weight. The reader may easily supply the
deficiency.
1818.] the Atoms of Chemical Bodies. 44)
Atoms of acid, base, Weicht of
‘ , and water. a particle,
199 Bisulphate of potash .... 25 + Llp ....- +206 16-000
200. Sulphate of soda. ...... lis + 1s + 10 water 9-000
201 Hydrous sulphate of lime. 1 s + 12 + 2water 8°625
202 Anhydroussulphateoflime 1 s + 1l ..........
203 Sulphate of barytes..... 1s + 10 ...cceeeee 14-750
204 Bisulphate of barytes. .. 2s + 10 .......0.. 19°750
205 Sulphate of strontian.... 1s + 1 str.......... 11-500
206 Sulphate of magnesia. .. 1 s + 1 m+ Swater 7-500
207 Sulphate of glucina..... 1 s + 1 gl.......... 8-250
208 Bisulphate of glucina.... 25 + 1 gl.......eee 13-250
cee erate On G2 # 8 Bhan coc enee 19°760
210 Sulphate of alumina. .... Ls’ #ocleousueialiahn. 7°125
211 Sulphate of iron....... ~ ls +12 + T7water 9500
212 Persulphate of ron..... 1s + Lt ...ce.eeee 15°000
213 Tripersulphate of iron. .. 3s + 12 ......e0e, 25-000
214 Sub-bipersulphate of iron 1 s + 272 .......... 25-000
215 Sulphate of nickel ...... ls + 12+ Twater 9:375
216 Sulphate of cobalt...... ls + le + Twater 9-625
217 Sulphate of manganese... 1 s + 1 m+ Swater 9°500-
218 Sulphate of zinc........ ls + 1x + Swater 10-125
219 Sulphate of lead. ...... Ascent?) Libel ante ee 19-000
220 Bisulphate of copper ... 2s + 1c + 10 water 20-000
221 Subsulphate of copper... 2s + 3 ¢ + 6water 40-000
222 Sulphate of bismuth .... ls + 16 .......... 14:875
223 Subsulphate of bismuth... 1 s + 3.6 .......05. 34625
224 Sulphate of mercury .... ls + lm..... vevee 31°000
225 Turpeth mineral, or per- ;
hea cae iS fayalky gg ENON Ce 32-000
226 Bipersulphate of mercury. 2s + 1 m.......ee 37:000
227 Sulphate of silver. ...... Lesieteinls ster. Re wee 19-750
228 Sulphate of platinum.... 1 s + 1 pl ........ee 28°625
ARTICLE V.
On the Action of Sulphurous Acid Gas on Sulphuretted Hydrogen
Gas. By Thomas Thomson, M.D. F.R.S.
Ir was first observed by Mr. Kirwan, that when sulphuretted
hydrogen gas was mixed with sulphurous acid gas, the bulk of
the two gases diminishes, and a quantity of sulphur is deposited
on the sides of the jar. He found that five measures of sulphu-
rous acid and six measures of sulphuretted hydrogen, when.thus
mixed, were reduced to three measures.* Qn turning to Messrs,
* Phil, Trans. 1786, p. 118,
442 Dr. Thomson on the Action of Sulphuretted Acid Gas [Drc.
Aiken’s Dictionary of Chemistry and Mineralogy, published in
1807, I find exactly the same experiments related as those pre-
viously given by Kirwan in his paper “On Hepatic Air.” I
conceive, therefore, that these gentlemen did not make any
experiments on the subject themselves ; but simply adopted Mr.
Kirwan’s results ; though the want of a reference to that gen-
tleman might at first lead to the notion that the experiments
related were their own. Thenard, in his “ Traité de Chimie,”
vol. i. p. 539, informs us, that the action of sulphurous «acid gas
on sulphuretted hydrogen gas has been fully examined : that the
two gases decompose each other reciprocally, and form water
and sulphur; that the action is instantaneous, if the gases be
moist ; but very slow if they be dry ; and that rather more than
two parts of sulphuretted hydrogen are requisite to decompose
one part of sulphurous acid.
These were all the circumstances respecting the action of these
two gases on each other which | could find in chemical books at
the time that I was employed in preparing the fifth edition of
my System of Chemistry for the press. As they did not appear
at all satisfactory, I found myself under the necessity of omitting
all attempts to explain this action in my System, and to place
the fact ear 5A list of subjects which required further inves-
tigation ; of which I found myself under the necessity of drawing
up a pretty copious list. These topics I propose to mvestigate
in succession ; and I shalllay the result of my experiments occa-
sionally before the readers of the Annals of Philosophy.
The gases employed by Kirwan were probably not absolutely
pure. He did not examine with sufficient care the volumes of
the two gases requisite to produce the greatest condensation ;
nor is his account of the properties of the residual gas sufficient
to enable us to understand its nature. There is the same want of
precision m the account given by Thenard. According to him,
rather more than two volumes of sulphuretted hydrogen are
decomposed by one volume of sulphurous acid gas, and the
result 1s water and sulphur. In these two gases the weight of
the atom is just double the specific gravity (supposing the speci-
fic gravity of oxygen gas to be unity). We may, therefore, sub-
stitute atom for volume.
Sulphur Atoms.
2 atoms sulphuretted hydrogen contain.. 2 atoms + 2 hydrogen
2 atom sulphurous acid contains. ...... 1 + 2 oxygen
From this it is obvious, that if the two gases decompose each
other, and form water and sulphur, they will be completely con-
densed when we mix two volumes of sulphuretted hydrogen
with one volume of sulphurous acid—proportions which do not
tally completely with the statement of Thenard.
n repeating the experiment over mercury with gases perfectly
pure and sufficiently dry, I found that the two gases are com- .
1818.] on Sulphuretted Hydrogen Gas. 443
pletely condensed; and lose their gaseous state entirely, when we
mix three volumes of sulphuretted hydrogen gas with two
volumes of sulphurous acid gas. Two volumes of the former,
when mixed with one of the latter gas, did not undergo complete
condensation. The substance formed was quite dry ; and I could
not separate any moisture from it by the application of heat, or
by any other method which I could think of. Hence we have
no experimental proof of the formation of water; nor is theory
more favourable to the notion. Let us substitute, as before, atom
for volume, that we may judge of the elements which have acted
on each other.
Atoms. Atoms,
3 atoms of sulph. hydrogen contain. .. 3 sulphur + 3 hydrogen
2 atoms sulphurous acid contain ...... 2 sulphur + 4 oxygen
So that there are present three atoms of hydrogen and four atoms
of oxygen. Were these bodies to unite and form water, it is
obvious that there would remain one atom of oxygen gas uncom-
bined, which would amount in bulk to the fourth part of the
sulphurous acid gas, or half a volume. In my experiment I
mixed over mercury 12 cubic inches of sulphuretted hydrogen
with eight cubic inches of oxygen gas. If Thenard’s statement
were accurate, namely, that water is formed during the action
of these two gases on each other, the residual oxygen gas would
have amounted to two cubic inches; whereas there was no
residue, except an insignificant bubble of common air not larger
than a pea.
I think after the preceding detail there cannot be a doubt
that the hypothesis of Thenard, that, when these two gases are
mixed, they are converted into water and sulphur, is inaccurate.
In reality, the two gases unite together and form a compound;
which has hitherto been mistaken for sulphur, though it
possesses properties somewhat different from that combustible
substance.
Its colour is orange-yellow, without any mixture of the green-
ish tinge which distinguishes sulphur. It is not tasteless, like
sulphur, but gives a sensibly acid impression to the tongue: this
impression becomes at last hot, or peppery, aud continues in
the mouth for a considerable time. When the dry compound is
applied to paper stained blue with litmus, it does not produce
any sensible change on it ; but if we moisten the paper ever so
little, it is immediately rendered red by it. Hence I conceive
that this compound possesses acid properties. But it is an acid
that cannot be applied to any useful purpose in chemistry, as it is
decomposed by all liquid bodies that I have tried; namely,
water, alcohol, nitric acid, sulphuric acid; and as it does not
sensibly unite with the salifiable bases when presented in a dry
state. The acid which gives the red tinge to vegetable blues is
neither the sulphuric nor sulphurous ; for when the compound is
444 Mr. Dalton on the Vis Viva. [Dzc.
agitated in barytes water, no immediate precipitate takes place ;
though if we boil the mixture, a dirty grey precipitate at last
falls.
When the compound is heated, it becomes soft and ductile ;
but requires for fusion a higher temperature than sulphur. But
if the heat be continued, a kind of effervescence takes place, and
the compound is converted into common sulphur, which burns
in the usual manner. =
When the compound is agitated with water, that liquid
becomes milky, acquires a slightly acidulous taste, and a quan-
tity of common sulphur is speedily deposited. The very same
decomposition is produced by alcohol.
With potash it does not combine unless water be present, and
in that case nothing is formed but common sulphuret of potash.
I have tried the action of various other re-agents upon this
compound ; but the phenomena presented were so little remark
able that they seem scarcely entitled to be related.
This is, perhaps, the first acid compound hitherto observed
which contains both oxygen and hydrogen united to a combus-
tible basis. Though of little importance in a practical point of
view, itis of some little value as far as the theory is concerned ;
for it possesses the properties of acidity in a very weak degree,
so much so that I have not been able to succeed in uniting it with
any salifiable basis. This, I think, is a sufficient proof that
Dr. Murray’s notion, that the greatest degree of acidity is given
to bodies by the jomt union of oxygen and hydrogen, is not coun-
tenanced by chemical facts, nor consistent with the phenomena
of the science.
[ have not given this new compound a name, because it is not
likely ever to be employed for any useful purpose. Perhaps the
term hydrosulphurous acid, though not quite correct, might be
applied to it without much impropriety.
ArTIcLe VI.
On the Vis Viva. By Mr. John Dalton.
(To Dr. Thomson.)
RESPECTED FRIEND, Manchester, Oct. 12, 1818.
In the Annales de Chimie et de Physique for last July, there
is a paper by: M. Petit on the employment of the principle of the
vis viva in the calculation of the effects of machines.
M. Petit expresses his surprise that so little attention has
hitherto been paid to this principle, which he considers to be
capable of general and highly interesting application. He
observes, the theory of machines considered with reference to this
1818.} Analyses of Books. . 445
principle requires to be almost formed anew. You will probably
recollect a paper “ On the Measure of Moving Force,” by Mr.
Ewart in the second volume (second series) of the Memoirs of
the Manchester Society, which was read Nov. 18, 1808. This —
paper was reprinted by Mr. Nicholson in the 36th vol. of his
journal, and it was also reprinted about the same time in the
Beeitory of Arts. You noticed it yourself in the Annals of
Philosophy, vol. i. p. 462, and again briefly in your review of
the progress of science during the year 1813, in vol. iii. of the
Amnals, p.8._ Excepting these, I do not know that any other
public notice has been taken of this paper.
I fully accord with M. Petit that our elementary treatises on
mechanics are extremely defective in developing the principles _
of moving force, and in their application to explain the action of
machines. The object of this letter is to recommend to
M. Petit, and to others who may be interested in the subject, to
peruse the above-mentioned essay. Mr. Ewart has pointed out
the source of numerous errors and inconsistencies in some of the
best writers on mechanics, and has, I think, succeeded in giving
satisfactory explanations of various cases (especially those in
which moving force is expended in producing change of figure),
which were before involved in much obscurity.
In estimating the power communicated by a stream of water
to an under-shot water-wheel, M. Petit gives the same result
which Mr. Ewart has given (p. 231), when supposing it to act in
a similar manner; and they agree also in their statement of the
maximum effect of the reaction of water in the machine known
by the name of Barker’s Mill, supposing the waters to issue with
the velocity due to the pressure. If M. Petit has not seen Mr.
Ewart’s paper, their agreement in these results is the more
remarkable ; as I believe they are different from those obtained
by all other writers who have attempted solutions of the same
cases. The investigation of both these cases, however, appears
to have been pursued considerably further by Mr. Ewart than
by M. Petit: and he has corroboratéd his conclusions by some
original and ably conducted experiments.
1 remain, yours truly,
Joun Datton.
/
ArTIcLe VII.
ANALYSES oF Books.
Philosophical Transactions of the Royal Society of London
for the Year 1818. Part Iv
This part contains the following papers :
I. On the great Strength given to Ships of War by the Appli-
cation of diagonal Braces. By Robert Seppings, Esq. F.R.S.
446 Analyses of Books. [Dee.
—Mr. Seppings begins his paper by assuring the society that the
principle of applying a diagonal frame-work to ships of war had,
as far as he knows, never been so applied either theoretically or
ractically either in this or any other maritime country till he
introduced it im the year 1805. The object of the paper is to
’ state an experiment upon the Justitia, an old Danish 74, which
was ordered to be broken up in 1817 on account of her defective
‘state. Mr. Seppings got a certain number of trusses to be placed
in the hold and the port-holes of this old ship, in order to ascer-
tain what the effect of these trusses would be when the vessel
was again floated. The experiment was successful. The report
of the committee of Portsmouth officers, which is given in the
aper, is exceedingly favourable to the trussing system. The
owe, of 120 guns, which was built according to this system,
when launched was found to have altered only 32 inches from
her original sheer ; while the Nelson and the St. Vincent, both of
the same size, but built according to the old system, altered, the
first 94 inches, and the last 9} inches. The report of the ship
Albion (built on the new plan), after the battle of Algiers, was
equally favourable. The Northumberland of 80 guns was laid
on one side fore and aft, on the other side diagonally. After she
conveyed Bonaparte to St. Helena, the fore and aft side required
caulking, the diagonal side did not.
II. A Memoir on the Geography of the north-eastern Part of
Asia, and on the Question whether Asia and America are conti-
uous, or are separated by the Sea. By Capt. James Bumey,
.R.S.—The object of this memoir is to show that there is no
evidence that Asia and America are separated from each other
by the sea; but that all the facts at present known concur to
prove that the two continents are united together. It was Mul-
ler, it seems, who first affirmed that the two continents were
separated by a narrow sea, and his opinion has been universally
adopted. Capt. Burney shows that no person has hitherto sailed
round the north-east coast of Asia. According to him, the
Russian navigators had never been able to double the promon-
tory called on that account swieto noss (sacred promontory). But
they were accustomed to construct vessels in such a manner that
they could be with ease taken to pieces; they were carried
across the land till they came to the sea, and then put together
again. I donotsee, however, any evidence which Capt. Burney
has actually produced that Deschnew, upon whose voyage Mul-
ler’s opinion is founded, really transported his ships or boats over
land to the sea of Kamschatka. Capt. Burney’s own opinion
was founded upon two facts which he observed when he accom-
panied Capt. Cook in his last voyage to Behring’s Straits. These
were, the disappearing of the tides and the sea becoming shal-
lower. These tworfacts indicated, he thinks, that the vessel had
got into an inland sea. But, perhaps, it would be rather hazar-
dous to consider these facts as decisive of the point. If the
whole surface of the sea to the north of Behring’s Straits was
1818.] Philosophical Transactions, 1818. Part I. 447
frozen, probably the ice might have just as great an effect in
destroying the tides as land would have. The shallowness of
the Frozen Ocean seems to be greater, according to the observa-
tion of Capt. Ross, at a distance from land than in its immediate
neighbourhood. Upon the whole, this point of geography does
not seem to be fully decided. Are we to hope fora full decision
of it from the voyage of discovery made last summer under the
command of Capt. Ross.
III. Additional Facts respecting the fossil Remains of an
Animal, on the Subject of which two Papers have been printed in
the Philosophical Transactions, showing that the Bones of the
Sternum resemble those of the Ornithorhynchus Paradovus. By
Sir Everard Home, Bart. V.P.R.S.—The author had been
favoured with several new specimens of the fossil bones of this
unknown animal by the Rev. Peter Hawker, of Woodchester
rectory, Minchinhampton, and Dr. Carpenter, of Lyme. He
has been enabled in consequence to ascertain a strong resem-
blance in the bones of the sternum to the ornithorhynchus para-
doxus. He has satisfied himself that the animal must have
breathed air, and that it must have lived constantly in the water.
IV. An Account of Experiments for determining the Length of
the Pendulum vibrating Seconds in the Latitude of London. By
Capt. Henry Kater, F.R.S.—This interesting experiment has
fortunately fallen into the hands of a gentleman whose sa gacity
and experimental skill have enabled him to do full justice to the
subject: hence there is every reason to be satistied that the
result obtained is exceedingly near the truth. His mode of expe-
rimenting was founded upon the known fact that the centres of
suspension and oscillation are reciprocal. He made these two
points alternately the points of suspension, and by shifting a
moveable weight rendered the number of oscillations the same in
equal times in both cases. The pendulum consisted of a bar of
platinum with three moveable weights. It moved upon aknife edge.
A minute account is given of the structure of this instrument, of
the mode of estimating the vibrations and measuring the length
of the pendulum. But for all this, we must refer to the paper
itself. The general result of the whole is, that a pendulum vibrat-
ing seconds in vacuo at the level of the sea, at the temperature of
62° Fahrenheit, in the north latitude of 51° 31’ 8-4” » has the fol-
lowing length :
Inches.
By Sir George Shuckburgh’s standard. .... 39-13860
By Gen. Roy’s standard. .:.:......0.002: 39°13717
By Bird’s parliamentary standard. ........ 39° 13842
Sir George Shuckburgh’s standard is preferred by Capt. Kater.
Bouguer found the length of the second’s pendulum at the equa-
tor 38°9949 English inches. It appears from Dr. Maskelyne’s
experiments (Phil. Trans. 1762, p. 434), that the length of the
9
448 Analyses of Books. [Dec.
second’s pendulum at St. Helena, lat. 15° 55’ S. is 39:04255
inches ; for Dr. Maskelyne found the length of the pendulum at
Greenwich to that at St. Helena as 10-0246 to 10.
V. On the Length of the French Metre estimated in Parts of
the English Standard. By Capt. Kater, F.R.S.—The result of
a very careful measurement by Capt. Kater is, that the length of
the metre is 39°37079 inches of Sir George Shuckburgh’s stan-
dard scale.
VI. A few Facts relative to the colouring Matters of some Vege-
tables. ‘By James Smithson, Esq. F.R.S.—The author refutes
an assertion of Fourcroy that turnsol is essentially of a red
colour, and that it contains carbonate of soda. The infusion of
turnsol contais no alkali, lime, nor acid, and its natural colour is
blue. When the colouring matter of turnsol is burned, it leaves
a saline matter which, with nitric acid, forms nitrate of potash.
Mr. Smithson suspects that this colouring matter, like wlmin, is
a compound of a vegetable substance and potash. The paper
contains experiments on the colouring matter of the violet, sugar-
loaf paper, the black mulberry, the corn poppy, sap-green, and
some animal greens ; but they are of so unconnected a kind that
they are scarcely susceptible of abridgement. We must, there-
fore, refer our readers to the paper itself.
VII. Account of Experiments made on the Strength of Mate-
rials. By George Rennie, Jun. Esq.—These experiments differ
a good deal from others of a similar kind given by former expe-
rimenters. Mr. Rennie found a cubical inch of the following
bodies crushed by the following weights :
Elth ome.) cement. Seeks Saar eR Se eO. Dae of 1284
American pine ....... Spe oblae, PIale al. Aer ies 1606
White dedhe saindiinad conedosmminds iain JA ee 1928
Poglish Gak=si2 wien tise saiae. Bis bi deb ALN Shih, OR 3866
Ditto of five inches long slipped with. .,..... PEL Ae 2572
Phitijo of four meheés ditto sash said aio 3'% dB Bile DOM ead S147
A prism of Portland stone two inches long. ............ 805
Ditto statuary marble .........0.2005 od hep ea eel ties (216
Craig Leith stone. .......... sible shea lidle lots nae .-.. 8688
Cubes of 12 inch.
Sp. gr.
Chitika: cae in ce wintukirche in et SROVeP ate oo ws ok bee
Brickwefat pale red colour),./.,. ostwavee yee es 2°085 3. «6/1265
Roe stone, Gloucestershire. ........ b avacbigit — .... 1449
Red brick, mean of two trials............-- 2168 <8 ge Loy
Yellow face baked Hammersmith paviors 2954
three times’. sas... Sid 2. i an ies te? tone A See
Burnt ditto, mean of two trials. ............ — 1... 3243
Stontbridge, or finevbtick: j5.2 0. «ie a. — .... 3864
Derby grit, a red friable sandstone......... 2316 .... 7070
1818.] Philosophical Transactions, 1818. Part I. 449
Sp. gr. lb. av.
Derby grit from another quarry.......... Poems > he
Killaly white freestone, not stratified. .... 2°423 .... 10264
Maret beara 8.36.23 an (nn
CADEMY of Sciences at Paris,
139, 225.
Acid formed by the slow combustion of
ether, 22. -
Adams, J., Esq.; formulas by, from
Lacroix’s differential and integral
calculus, 204,
ars Peak, geological account of,
3.
Africa, attempts to penetrate into the
interior of, 72.
Aikin, Arthur, Esq., on the valleysand
water-courses of Shropshire, 69—on
a bed of trap in a colliery near Wal-
sall, 134.
Albin, 310.
Alcohol, union of, with oxalic acid, 23
—action of, onoil of bergamotte, 150
—combustion of, by a lamp without
flame, 245.
Alison, Rev. A., biographical account
of Lord Woodhouselee, 401.
Alkaline sulphurets, nature of, 24.
Allan, T., Esq., on the gevlogy of the
environs of Nice, 383.
Almonds, 39.
Alumina, preparation of, 24.
Animal substances, composition of, 40.
Annular eclipse of the sun, 179, 249.
Aqua regia, action of, on antimony, 21.
Arsenic, new method of detecting, 8.
Atmospherical phenomena, near Gos-
port, 235, 368.
Atoms of chemical bodies, weight of,
338, 436.
Axinite, existence of boracic acid in,
314.
Azote, nourishing properties of sub-
stances destitute of, 39.
B.
Bacon, Lord, on the scope and influence
of his writings, 382.
Baily, Francis, Esq., on av annular
eclipse of the sun, 179, 249.
Barley, analysis of, 201.
Bauhof, M.J.C. D., on the union of al-
cohol and oxalic acid, 23.
Beaufoy, Col., astronomieal, magneti-
cal, and meteorological observations
by, 76, 154, 236, 316, 396, 470—on
the spiral oar, 246.
Berard, M., onthe composition ofanimal
substances, 40.
Bergamotte, oil of, action of alcohol on,
150.
Bergman, Sir Torbern,
account of, 321.
Bertbollet, M., on the elements of nitric
acid, 350.
Berzelius, Professor, on peroxide of tin,
i7—on the composition ef certain
carbonates, 30—on the colouring mat-
ter of the blood, 42.
Beudant, M., on the property of certain
salts to give their crystalline forms to
others, 27.
Bilberry, experiments on, 232.
Black-lead mine in Glen Strath-Farrar,
453.
Boiling point of fluids, on, 129.
Bombay, weather in, 209.
Bones, fossil, near Margate, 70.
Boracic acid found in tourmaline and
axinite, 314,
Borax, action of, on tartar, 113,
Boston, diary of the weather at, 436.
Braconnot, M., on extractive, 34—ana-
lysis of rice by, 38—on sorbic acid,
290.
Brass, analysis of, 19.
Breguet, M., metallic thermometer by,6.
Brewster, Dr., on the primitive form of
carbonate of lime, 69—on the laws of
polarisation and double refraction in
crystals, 45}—on the absorption of
polarised light by crystals, 452.
Brisbane, Sir T., on a method of deter-
mining the time with accuracy, from
aseries ofaltitudes of the sun taken on
the same side of the meridian, 384.
Brisson, M., biographical sketch of, 43.
Brugnatelli, M., on metallic alloys ob-
tained by galyanism, 228.
Bucholz, Prof., analysis of tungstate of
lime, by, 388.
Buckland, Prof,, on an insulated group
of slate and greenstone rocks in Cum-
berland and Westmoreland, 223.
Burney, W., Esq., on parheliaseen near
Gosport, 235, 368.
Capt. James, on the geography
of the north-eastern partof Asia, 446.
Cc.
Cadmium, properties of, 152.
Calculus, Lacroix’s differential and inte.
gral, formulas from, 204,
biographical
476 Index.
Caldas de Rainha, mineral spring of,
analysis of, 31.
Cambridgeshire, strata of, T0—geology
of, 133.
Camphor, effect of, on heated platinum
wire, 143.
Carbonate of lime, on the primitive
form of, 69.
Carbonates, composition of certain, 20.
Carrots yield manna, 39.
Cetine, 41.
Chamelion mineral, experiments on, 18,
Charcoal, metallic, of Dobereiner, ana-
lysis of, 13.
-Chaudet, M., analysis by, of tin, alloyed
with antimony and bismuth, 20.
Chemistry, improvements in, during
1817, 1.
Chenopodium olidun, analysis of, 231.
Chevalier, M., on the analysis of cheno-
podium olidum, 231.
Chevillot and Edwards, MM., on cha-
melion mineral, 18.
Chevreul, M., on chamelion mineral, 18
—on the acidity of peroxides of tung-
sten and uranium, 144—on fatty
bodies, 186, 257.
-Chloric acid, new mode of forming, 22.
’ Chlorides, combination of, with ammo-
nia, 26. ,
Chromate of iron in the Ferroe islands,
453.
Clarke, Dr., on the colouring consti-
tuent of roses, 126, 296—on the disco-
yery of pearl-sinter, 463.
Clay, plasticity of, ascribed to water,
A63.
Cotour of bodies, on the cause of, 146.
Comets, on the tails of, 227.
Copper, traces of, in plants, 39.
Cork, meteorological journal at, 123,
43},
Corn, analysis of, 37— oils contained in,
35
Cornwall, new literary institution in,
395—RoyalGeologicalSocietyof,465.
Corrosive sublimate, new mode of
detecting, 8.
Coulomb, M.C.A., biographical sketch
of, 81.
Cow-tree, milk of, 115.
Cumberland, G.,Esq., on encrinital and
pentacrinital bodies, near Bristol, 70
—on Bristol limestone beds, 70.
D.
Dalton, Mr. John, onthe combustion of
alcohol by alamp without flame, 245
—on the vis viva, 444.
Davy, Sir H., researches on flame by, 3
—obtains lithium, 16—on the fallacy
of the experiments in which water is
said to have been formed by the de-
composition of chlorine, 450.
Davy, Dr. J., on the situation of gems in
Ceylon, 143—geological description
of Adam’s Peak, by, 143. ‘
Delcros, barometrical measurement of
Jura, by, 355.
Dick, T. L., Esq., on the Fountainhall
chalybeate spring, 91.
Dinsdale, W. M., on the management of
dung-hilis, 464.
Dolomieu, M., biographical account of,
161.
Donovan, Mr., on the oxides of mercury,
67.
Durham, geology of, 220.
E.
Egerane, 311.
Elephant, gases in the intestines of, ana-
lyzed, 119,
Emetin, 36.
Ether, acid formed by the slow combus-
tion of, 22.
Eudiometer, Volta’s, improvement in,
by Gay-Lussac, 11—ditto, by Dr. Ure,
381.
Extractive, Braconnot on, 34.
Eye, newly discovered membrane in, 74.
lhe
Faraday, Mr., on the escape of com-
pressed gases, S—on sulphuret of
phosphorus, 12—on a supposed new
oxide of silver, 25—on the formation
of fulminating silver, 26—on the com-
bination of the chlorides with ammo-
nia, 26,
Fat, conversion of animal bodies into,
Al.
Fatty bodies, on, 186.
Finch, J., Esq., on some basalticcolumns
in Staffordshire, containing mesotype,
prehnite, and barytes, 167.
Fire-places to steam-boilers, on the
construction of, 51.
Flame, researches on, by Sir H. Davy, 3.
Flaugergues, M., on the tails of comets,
227.
Fountainhall chalybeate spring, on, 91.
Fleming, Rev. Dr., on the junction of
the fresh water of rivers with the salt
of the sea, 384,
G.
Garlic, 36.
Gases, time they take to escape through
small orifices, 8—specific gravity of,
9—in the intestines of an elephant
analyzed, 119.
Gautier, M., on the pellitory of Spain,
229.
Gay-Lussac, M., hydrogen gas lampby,
5—analysis by, of the metallic char-
coal of Dobereiner, 12—on alkaline
sulphurets, 24—en the property of
‘y
Index.
tartar to dissolve oxides, 28—oun the
boiling point of fluids, 129.
Gehlenite, 311.
Geological Society, meetings of, 69,
137—Royal, of Cornwall, 465.
Giesecke’s travels in Greenland, notice
of, 149,
Gilby, Dr., on the magnesian limestone
near Bristol, 224.
Gill, Thos., Esq., on softening steel,
58—on brass, 125—on improvements
in the manufacture of superfine cloth,
212—on improvements in printing,
300.
Gilpin, Rev. W., on fossil bones near
Margate, 70. 8
Girard, M., on the flow of liquids
through capillary tubes of. glass,
230.
Glasgow, on the annual fall of rain at,
SUL.
Glen Tilt, seological description of, 134.
Granite veins, on, 70.
Granville, Dr., on sulphuretted azote,
67. :
H.
Hailstone, Professor, on the geology of
Cambridgeshire, 133.
Halifax, diary of the weather at, 435.
Hansteen, Prof., on the magnetism of
the earth, 389.
Haiiy, M., on magnetism considered
as a method of detecting iron, 117.
Haiiyne, discovery of, in the island of
Tyree, 387.
Heat, experiments on, by Dulong and
Petit, 2.
Heat, animal, diminished when animals
breathe on their backs, 4,
Hlelvin, 3il.
Henderson, Mr., on Iceland, 301.
Herschell, T. F. W. Esq., oncirculating
functions, 450.
Heuland, H., Esq., on a mass of plati-
num in Madrid, 200—account of
some new minerals, 453.
Holt, T., Esq., meteorological journal
at Cork by, 123, 431—on the effect
of air in restorivg the colour of in-
digo, 123.
Home, Sir E., on the teeth of the del-
phinus gangeticus, 67—on the fossil
remains of an animal supposed to be
the ornithorhynchus paradoxus, 447
—on the chunges the blood undergoes
in the actof coagulation, 450—on the
formation of granulations, 451.
Horner, Leonard, Esq., on the geology
of the south-western parts of Somer-
setshire, 136.
Houton-Laballardiere, M., on the union
of hydriodic acid with phosphuretted
hydrogen, 22, 233.
A477
Howard, L., Esq. meteorological tables
by, 79, 157, 159, 239, 319, 399, 473.
Humboldt, M., on vegetable milk, 116.
Hydriodic acid, uniou of, with phes-
phuretted hydrogen, 22, 233.
Hydrocyanic acid, amost violent poison,
23.
Hydrogen gas, lamp, 5—how purified,
12.
Hydroguretted carbonic oxide, 104.
JT, and J.
Ibbetson, Mrs., on the injurious effects
of burying weeds, 87.
Iceland, journal of a residence in, 30].
Tilumination of streets, on, 145.
Tpecacuanha, 36.
Treland, geological relations of the easé
of, 137.
Iron, perquadrisulphate of, 461.
ore, hills of, in Brasil, 453.
—— chromate of, in Ferroe, 453.
rails, on the decay of, 455,
Jura, barometrical measurementof, 355.
K,
Kaleidoscope, history of, 59.
Kater, Capt. H., on the length of the
pendulum, 447—on the length of the
French metre, 448.
Knebelite, 391.
Knight, T. A., Esy., on the office of the
heart-wood of trees, 450.
Koelreuter, M., on the sand of the
Rhine, 390.
Kupfernickel, analysis of, 152.
L.
Lasseigne, M., on the analysis of the
chenopodium olidum, 231,
Laugier, M., on the juice of carrots, 39.
Lead, crystals of protoxide of, IT.
Legallois, M., experiments on animal
heat by, 3.
Leslie, John, Esq., on certain impres-
sions of cold transmitted from the
higher atmosphere, 383.
Light, violet rays of, said to induce
magnetism in needles, 1.
Lillington, A. S., Esq., on granite
veins and whin dykes, 70,
Lime, separation of, from magnesia, 8.
Linnzan Society, meetings of, 71.
Linzinite, 71.
Liquids, flow of, through capillary
tubes of glass, 230.
Lithina, account of its properties, 15.
Lithium, 16,
Loo-choo island, method of making salt
in, 145.
Lunn, F., Esq., on the strata of north
Cambridgeshire, 70.
Lyall, Dr., accountof the Natural His-
tery Society of Moscow, by,12i.
3
M.
M‘Culloch, Dr., geological description
of Glen Tilt by, 134.
Magendie, M., on hydrocyanic acid, as
a poison, 23.
Maguesia, separation of, from lime, 8,
393.
alba of the shops, 386.
Magnesian limestone near Bristol, on,
224.
Magnetism, on, as amethod of detecting
iron, 117.
Malic acid, experiments on, 153.
Malton New, register of the weather af,
A459.
Manna, experiments on, 153.
Meinecke, Prof. on the specific gravity
of gases, 9.
Mercury, oxides of, on, 67.
Metallic sulphurets, composition of, 16
—alloys obtained by means of gal-
vanism, on, 228.
Metals, relation between their oxida-
tion and specific gravity, 7—influence
of, on the production of potassium
with charcoal, 16,
Meteorological period of 18 years, on,
459.
Mica, two species of, 70.
Milk, vegetable, 35, 116.
Millington, Jobn, Esq., on street illu-
mination, 145.
Montreal, meteorological observations
made at, 432.
Morichini, M., on the magnetic effects
of light, I. :
Morphium aud meconicacid, 55.
Moscow, Natural History Secciety of,
account of, 121.
Munche, Prof,, on the fixedness of the
boiling point in thermometers, 131.
Murray, J. Esq., on native phosphate
of iron, 147.
N.
Napier, Macvey, Esq., on the scope
and influence of Lord Bacon's writ-
ings, 382.
Necker, M., on thediscovery of Haiiyne
in Tyree, 387.
Nice, on the climate of, 169—geology
of the environs of, 383.
Nitric acid, on the elements of, 350.
Northumberland, geology of, 221.
North-west expedition, 391—notice
of animals from, 468,
Nux vomica, new alkali in, 314.
oO.
Oar, spiral, on the, 75.
Qils contained in corn, 35.
Olivile, 38.
Opal, two mines of, in Mexico, 200.
QOxalic acid, union of, withalcohol, 23,
Index.
r.
Pargasile, 73.
Parhelia, seen near Gosport, 235, 368.
Paris, Dr., plate presented to, 74.
Pear] Sinter, on the discovery of, 463.
Pelium, 314.
Pelletier, M., on olivile, 33.
Pelletier and Magendie, MM., on eme-
tine, 37.
Pellitary of Spain, chemical remarks
on, 229,
Peschier, Dr., on the state of potash in
vegetables, and on the saccharine
matter of the potatoe, 336.
Philadelphia, Academy of Natural
Sciences in, 385.
Philips, Mr. R., onthe blue and green
carbonates of copper, 30-
— Mr. W., on oxide of uranium
found in Cornwall, 133.
Dr. Wilson, on stimulants and
sedatives, 372.
Phosphate of iron, native, found in the
Isle of Man, 147.
Photometer, Horner’s, 147.
Picrotoxin, 313,
Pike, eggs of, analysis of, 148.
Plants, on the geography of, 45.
Platinium, sulphuret of, 18—salts of, 28
—mass of native, 200,
Pond, Mr., on the parallax of the fixed
stars in right ascension, 67. ;
Porrett, Mr., on triple prussiate of pot-
ash, 214,
Potash, state in which it exists in vege-
tables, 336.
Potatoe, saccharine matter of, 337.
Potatoes, experiments on, 39.
Prehnite, found at Woodford, Glouces-
tershire, 395,
Prevost, M. Ben., on the cause of the
colours of bodies, 146,
Printing, improvements in, 300,
Proteus anguinus, on, 310.
Proust, M., analysis of barley by, 201.
Prout, Dr., on the composition of ant-
mal substances, 41—on purpuricacid,
68.
Purpuric acid, on, 68.
R.
Rennie, G. Jun., on the strength of ma-
terials, 448,
Rice, analysis of, 38, 151.
Ridolphi, M., on the magnetical effects
of light, 2.
Robiquet, M., on the formation of butter
of antimony, 21.
Roses, colouring constituent of, 126,296.
Royal Society, meetings of, 67, 451.
———— Transactions of, 445.
——- of Edinburgh, Transac-
tions of, 378,
Index.
Ss.
Salt, method of making, in the great
Loo-choo island, 145.
Saltness of the sea, 32.
Sand of the Rhine, nature of, 390.
Santi, Prof., the discoverer of pearl-
sinter, 443,
Sedatives, on, 372.
Selenium, properties of, 13.
Senebier, M., biographical account of,
241.
Seppings, Mr., on the use of diagonal
braces inship-building, 448,
Serpentine, on, 468.
Shropshire, on the valleys and water-
courses of, 69,
Silver, solution ef oxide of, in ammonia,
25—fulminating preparation of, 26—
from luna cornea, easy method of
obtaining, 143.
Sirium, 312.
Smithson, J., on the colourigg matters
of vegetables, 448. :
Soaps, op, 27.
Somersetshire, geology of the south-
western part of, 135,
Sorbic acid, on, 22, 290.
Spiders devour sulphate of zinc, 454,
Spiral oar, on, 246.
Spodumene of the Tyrol}, 392.
Steel, on softening, 58.
Stimulants, on, 372-
Storm in Sussex in }729, 49,
Stromeyer, M., analysis of kupfernickel
by, 152.
Sulphate of nickel, form of the crystals
of, 28.
454,
Sulphur, action of, on the muriates,
393.
Sulphuret of phosphorus, on, 12.
Sulphurous acid and sulphuretted hy-
drogen, compound of, 441,
Syme, J., Esq., on coal naphtha as a
solvent of caoutchouc, 112.
Syoovia of an elephant, analysis of,
120.
— zinc devoured by a spider,
ae
Tantalite found at Bodenmais, 393.
Tar, coal, substance from, dissolves
caoutchouc, 112.
Tartar, property of, to dissolve oxides, 8
—action of, on borax, 113.
Taylors, Messrs., on the construction of
fire-places to steam-boilers, 51.
Thermometer, metallic, 6.
Thomson, Dr. Thomas, histery of che-
mistry for 1817 by, 1l-—analysis of
brass by, 19—on triple prussiate of
potash, 102—biographical account of
Bergman by, 321—on the weight ofthe
atoms of bodies, 333, 436—on the rain
479
which falls in Glasgow annually, 376
—on the magnesia alba of the shops,
386—on the action of sulphurousacid
gas on sulphuretted hydrogen, 441—
on perquadrisulphate of iron, 461—
on serpentine, 463.
Tiarks, Dr., table for computing heights
by the barometer, 456.
Tin, peroxide of, 17—and antimony,
alloy of, analysis of, 20—and bis-
muth, alloy of, analysis of, 21—and
lead, alloy of, analysis of, 21.
Tortoises, respiration of, 42.
Tourmaline, existence of boracic acid
in, 314,
Trap, on a bed of, inacolliery near
Walsall, 134.
Triple prussiate of potash, on, 102, 214.
Tritton, Mr., on the distilling apparatus
of, 75, 234.
Tungstate of lime, analysis of, 388.
Tungstic acid, acidity of, shown, 144.
Tytler, Hon. A. F., biographical ace
count of, 401.
V and U.
Vauquelin, M., on the production of
potassium, 16—on sulphuret of plati-
num, 18—on the salts of platinum,
28—on spurred rye, 36—on potatoes,
59—analysis by, of the gases in the
intestines of an elephant, 119—analy-
sis by, of the synovia of an elephant,
120—analysis by, of the eggs of the
pike, 148—on sorbic acid, 295—on
the action of alcohol on oil of berga-
motte, 150—analysis of rice by, 151.
Viper, poison of, 42.
Vis viva, on, 444,
Vegel, M., analysis of different species
of corn by, 3%7—on the action of
borax on tartar, 112—on the bilberry
and the colour of wine, 23l—on the
action of sulphur op the muriates,
393.
Uranium, union of its peroxide with
carbonate of potash, 3l—oxide of,
found in Cornwall, 133—on the acid-
ity of peroxide of, 144.
Ure, Dr. Andrew, on the relations
between muriatic acid and chlorine,
378,
Urinary calculus of a horse, 43.
Ww.
Wallerite, 71.
Warburton, H., Esg., on chromate of
iron as a volcanic production, 139.
Weaver, Thomas, Esq., on the geologi-
cal relations of the east of Ireland,
137.
Weeds, injurious effects of burying, 87.
Wheeler, James Lowe, on the mode of
obtaining chloric acid, 22,
480
Whin dykes, on, 70.
Winch, N. J., Esq., 09 the geography of
plants, 45—on the geology of North-
umberland and Durham, 221.
Wine, how extraneous colouring matter
in, is detected, 231.
Wistar, Dr., biographical notice of,
228.
Wollaston, Dr., oD the property of
certain salts to give their crystalline
forms to others, 28.
Woodhouselee, Lord, biographical ac-
count of, 401.
Index.
Wronski’s mathematical works, on, 455.
Z.
Zaire, river, observations on, 53—on
the collection of plants formed near,
21T.
Zinc, sulphate of, devoured bya spider,
Ab4.
Zumic acid, the same with lactic acid,
391.
END OF VOL. xil.3
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