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CHAPTER II.

PHYSICAL AND MATHEMATICAL.

Comprising the chief productions of France, Germany, Sweden.

N the department of medicine, M. E. Duvillard has furnished us with a very valuable and laborious work in his " Analyse et Tableaux de l'Influence, &c." "Analysis and Tables of the Influence of the Small Pox on Mortality at all ages; and of the Influence which such a preservative as Vaccination may have on Population and Longevity, 4to, Paris." The best inquiries which have hitherto been pushed into this subject, are those of Daniel Bernouilli, published in the volume of the French Academy of Sciences, for the year 1760; and that of D'Alembert, published in the same work in the year ensuing, with a view of controverting some of Bernouilli's results. The question is here examined upon other grounds than those of statistics, which, in point of fact, do not go to the root of the inquiry; mathematics, in the papers before us, add their aid to statistics, and the investigation is continued through the medium of the differential and integral calculus. The analysis and tables before us are conducted upon the same principles, and with a direct reference to the antecedent labours of these great calculators; and M. Duvillard has a very considerable advantage over his predecessors, by being able to draw a great body of facts from the effect of vaccination, as a supposedly perfect preservative, and to muster them as a datum of new power and influence. It is not sufficient," he

observes, " in order to ascertain the influence of the small-pox on the mortality of each age, to know the proportion of deaths produced by it, compared with deaths produced by other diseases; it is equally necessary that the following important questions should also be resolved: What are the laws of the mortality of a given country, and the number of persons living at different ages in the natural state? What the number of those who have never had the small-pox? Of these again, how many annually catch it, and under what ages? Of these moreover, how many die, and under what ages? Amongst those who have died of other diseases than the small-pox, how many have not received this complaint, together with their different ages? What is the law of the mortality of those who have had the smallpox, and of those who have never had it?" Among the more extraordinary results obtained by M. Duvillard, it appears that the mortality of catching the small-pox increases and decreases in a small degree only with the danger of dying when attacked by this disease; and that the disease is less dangerous after the age of twenty-nine, and in proportion to the patient's advance in years beyond this period. We are not quite satisfied, however, with the nature or extent of the tables upon which this last result is founded, yet we cannot avoid observing, that the vaccinists of our own country, in calculating

calculating the actual saving of life to the community, by the introduction of vaccination, admitting it to be a complete prophylactic, have reasoned very inconclusively while confining their observations to a mere comparison of the effects produced by vaccination and variolation. The aggregate of life and population, in a statistic view, can only fairly be contemplated in conjunction with a variety of other causes, or agents, which ought not to be separated from these. We shall conclude with observing, that one of the chief objects of the book before us is, to recommend vaccination from a mode of reasoning that has not hitherto been applied to it, and.which is, nevertheless, perhaps possessed of as much, or more validity, than any that has hitherto been brought forwards.

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"Recherches Physiologiques sur la Vie et la Mort, &c." "Physiological Inquiries concerning Life and Death, by M. X. Bichat, physician of the Hotel Dieu, professor of anatomy, physiology, &c." This is the work of a man of some judgment, but of more fancy; yet who has certainly studied his subject with minute attention, and whose theories are entitled to respect. It consists of two parts-Inquiries concerning Life-Inquiries concerning Death. Life," observes our author, "is the union of those functions which resist dissolution." This, however, is a vague and unsatisfactory definition; it gives us nothing tangible or substantive; a union of functions should imply a something that performs those functions, and upon which such an union operates. What is this something? We are completely out at sea, and without heini and compass. Living organised bodies, we are told, are surrounded by agents of destruction. Upon such living bodies, inorganic

bodies act incessantly, and a mutual conflict is the result. Life is alone preserved by a permanent principle of re-action, which is here supposed to be the principle of life, and which is only known by its phænomena. Life is divided into animal and organic; and each of these into two orders of functions: the existence of animal life is evidenced in man, and other animals; that of organic life in vegetables. The first order of animal functions is, that which communicates the impressions of the senses to the brain; the second, that which communicates the inpressions of the brain to the organs of loco-motion; the first comprises sensation, the second volition. The first order of the functions of organic life is denominated composition, resulting from digestion, circulation, respiration, and nutrition. This illustration is unquestionably gratuitous and fanciful; for the second quali y is often incapable of proof in the subjects of mere organic life, the third nearly as often incapable, and the first equally so in various instances. In tde author's inquiries concerning death, which constitute his second part, he observes, that in all sudden deaths, the organic survives the animal life a certain greater or less time, and that the contrary cannot happen, though the death of both may, in some cases, be nearly synchronous. This, however, is by no means correct; for, on various occasions, both kinds of death may be perfectly synchronous; and we now allude to death from electricity or lightning, and from a sudden and violent blow on the stomach. Of sudden death, indeed, produced by a violent blow on the stomach, so fully examined into by the late Mr. John Hunter, and accompanied with the very extraordinary phænomenon of a destruction of the coagulability of the

blood

country has of late years paid great attention to the subject of the present work; yet such is the intractable nature of the materials it comprises, and so destitute are they of those obvious characters which discriminate the animal and vegetable kingdoms, as to render it still capable of an improved arrangement. Hither to we have had minerals distributed under the one or the other of the three following systems: that of their external character--that of their interior structure-that of their elementary composition. The first forms the most obvious mode of discriminating them, and were it susceptible of sufficient accuracy, it ought immediately to supersede every other. In the hands of M. Werner, this method has certainly been advanced to a very considerable state of precision; and since the publication of his tract on the External Characters of Minerals, in 1774, a new school has been founded, whose influence is rapidly extending over Europe. Yet this system is loaded with that common fault of the German philosophers, a most wearisomie subdivision; its language is also, for the most part, harsh and unclassical; and it betrays, in a variety of instances, an undue inclination to bend the course of facts from a right line to the figure that will best support its principles. For the groundwork of the second system we are, in the first place, indebted to Linnéus ; the plan was improved by Bergman; still farther advanced by Romé Delisle, and brought to its present state of perfection by the very valuable labours, and indefatigable attention of Häuy. The third method would perhaps be the most satisfactory of the whole, if it had not a variety of pertinacious obstacles to its general adoption. It is, in the first place, extremely operose; it

involves, next, the destruction of a part or of the whole of the specimen to be analysed, and hence must be often accompanied with a very heavy expence; and lastly, we are not yet acquainted with a sufficient number of tests, or instruments of convenient use, to be able to resort to it as a ground-work of universal application. It is the peculiar advantage of the work before us, that it endeavours to extract from these three systems, their most prominent features, and such as are best calculated to amalgamate. It is, on this account, unquestionably superior, in every essential point, to any treatise upon mineralogy we have hitherto seen, and is enriched with a vast mass of knowledge disposed in a luminous order, and condensed into a convenient brevity. The author has not confined himself to a bare description of minerals, but has given a large portion of variety and interest to his work, by noticing their application to the arts, by sketching their natural history, or by indicat ing the geological theories which. have been proposed to explain their formation. The concise view of mining and metallurgy, subjoined to the treatise, as it includes the most recent improvements in those branches, is peculiarly valuable; and we cannot but applaud the judgment and impartiality which the author has every where displayed. The following is the classification under which the subject is treated: I. Combination of oxygen, with substances that are not metallic. II. Salts that have not a metallic base. III. Stones. IV. Combustibles. V. Metals. These five classes are subdivided into orders, genera, and species. Salts constitute two orders, those with an alkaline, and those with an earthy base. Stones give rise to three orders, hard, unctuous,

and

and argilloid. Metals are distinguished, as usual, into brittle and ductile. The numerous subdivisions are exhibited in a convenient synoptic table, prefixed to the body of the treatise.

“L'Art de la Teinture du Coton en Rouge, &c.""The Art of Dyeing Cotton Red, by M. J. A. Chaptal, Member and Treasurer of the Senate, &c. Svo. with four plates, Paris." There is no person to whom the perfection of modern manufactures is more indebted than to the indefatigable writer before us; who, with a singular and most fortunate union of talents for science and practical labour, has for many years devoted a large portion of his time to the improvement of almost every art that has any connection with chemistry. The general principles of dying were first developed by Bergman; the theory was considerably advanced by Berthollet, to whom the work before us is dedicated; and, if not brought to the highest state of perfection of which it is capable, is at least very considerably perfected by M. Chaptal. We may peruse this book, therefore, with a twofold advantage, since it not only presents us with the ideas of an enlightened philosopher, but contains the result of an extensive application of them to actual practice; for M. Chaptal informs us, that he has for some time conducted a large dying manufactory, in which every individual process recommended in this volume has been sanctioned by ample experience. The first two chapters are introductory, and describe the situation proper for a dyeing establish ment, the arrangements necessary for its various processes, and the instruments requisite to be employed. The third chapter considers the materials had recourse to in dyeing cotton by madder, viz. the madder

itself, oliveoil, soda, alum, and galls, Chapter four contains minute details respecting the various manipulations of different parts of the process: and chapter five gives an equally distinct account of the means by which the cotton is made to assume the dye. The operation is divided into four stages-the preparation of the cotton-the application of the mordants-the application of the madder-and the brightening of the colour. The mordants employed are alum and galls, and the colour is brought out by nitrat of tin.

In our survey of the higher branches of physical philosophy, we shall commence with noticing a Ger man work of some consequence, from the pen of M. Schroeter, entitled "Seleno-Topographische Frag menter and Beomachtunger, &c." "Seleno-Topographical Fragments and Observations, with a view to an exact Description of the Moon, the changes to which she is liable, and the nature of her atmosphere; to which are subjoined Maps and Drawings. Gottingen, 4to, with 32 engravings." M. Schroeter is by no means unknown to our own countrymen, nor is the fame he has acquired amongst us of a vulgar kind. He is a valuable Fellow of our Royal Society, and his paper on the planet Vesta, inserted of late in the Transactions of the Royal Society, cannot fail of being known to the scientific readers of this excellent journal. He has for many years, moreover, been particularly patrouised by his Britannic Majesty, by whom the most valuable of the astronomical instruments, lately at least, in the possession of the University at Gottingen, were presented gratuitously; and to whom, in proof of his grautude, M. Schroeter has dedicated the work before us. For the rest, together with much accuracy of re

mark,

country has of late years paid great
attention to the subject of the pre-
sent work; yet such is the intrac-
table nature of the materials it com-
prises, and so destitute are they of
those obvious characters which dis-
criminate the animal and vegetable
kingdoms, as to render it still capable
of an improved arrangement. Hither.
to we have had minerals distributed
under the one or the other of the
three following systems: that of their
external character-that of their in-
terior structure-that of their ele-
mentary composition. The first
forms the most obvious mode of dis-
criminating them, and were
and were it
susceptible of sufficient accuracy, it
ought immediately to supersede every
other. In the hands of M. Werner,
this method has certainly been ad-
vanced to a very considerable state of
precision; and since the publication
of his tract on the External Charac-
ters of Minerals, in 1774, a new
school has been founded, whose in-
fluence is rapidly extending over
Europe. Yet this system is loaded
with that common fault of the Ger-
man philosophers, a most wearisome
subdivision; its language is also, for
the most part, harsh and unclassical;
and it betrays, in a variety of in-
stances, an undue inclination to bend
the course of facts from a right line
to the figure that will best support
its principles. For the ground-
work of the second system we are,
in the first place, indebted to
Linnéus; the plan was improved
by Bergman; still farther advanced
by Romé Delisle, and brought to its
present state of perfection by the
very valuable labours, and indefati-
gable attention of Häuy. The third
method would perhaps be the most
satisfactory of the whole, if it had not
a variety of pertinacious obstacles to
its general adoption. It is, in the
first place, extremely operose; it

involves, next, the destruction of a
part or of the whole of the specimen
to be analysed, and hence must be
often accompanied with a very heavy
expence; and lastly, we are not yet
acquainted with a sufficient number
of tests, or instruments of convenient
use, to be able to resort to it as a
ground-work of universal applica-
tion. It is the peculiar advantage
of the work before us, that it endea-
vours to extract from these three
systems, their most prominent fea-
tures, and such as are best calculated
to amalgamate. It is, on this ac-
count, unquestionably superior, in
every essential point, to any treatise
upon mineralogy we have hitherto
seen, and is enriched with a vast
mass of knowledge disposed in a lu-
minous order, and condensed into a
convenient brevity. The author has
not confined himself to a bare de-
scription of minerals, but has given
a large portion of variety and in-
terest to his work, by noticing their
application to the arts, by sketching
their natural history, or by indicat
ing the geological theories which
have been proposed to explain their
formation. The concise view of
mining and metallurgy, subjoined to
the treatise, as it includes the most
recent improvements in those
branches, is peculiarly valuable;
and we cannot but applaud the
judgment and impartiality which the
author has every where displayed.
The following is the classification
under which the subject is treated:
I. Combination of oxygen, with sub-
stances that are not metallic. II.
Salts that have not a metallic base.
III. Stones. IV. Combustibles. V.
Metals. These five classes are sub-
divided into orders, genera, and
species. Salts constitute two orders,
those with an alkaline, and those
with an earthy base. Stones give
rise to three orders, hard, unctuous,

and

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