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he suspended a pewter-plate with 16 eggs on the conductor of the electrical machine, and kept his apparatus during eight days, and as many nights, in a degree of electricity as near as possible to that which corresponds (if the expresion may be allowed) with 32 degrees of heat. The success of this experiment confirmed the conjectures of M. ACHARD. Opening one of these eggs at the end of the first 48 hours, he perceived a small beginning of the formation of the embryo, and he discerned plainly the progress of this formation by opening an egg every day; but an accident that disconcerted his apparatus prevented his continuing his electrical operations to the birth of the chicken. This successful beginning, however, will encourage new trials.
Memoir. Concerning the Mandragora, or Mandrake. By M. GLEDITSCH.-Philologifts, naturalists, commentators, and wags have contributed to the propagation of the filly or indecent fables to which this plant has given occasion, and which M. Gleditsch has exposed as they deserve, in this learned Diflertation.
Memoir. Concerning the Colours of Vegetables. First Part. By M. ACHARD. Philosophers and chemiils are not yet agreed about the true cause of the colours of vegetables; nor has this matter been treated hitherto with the attention it deserves. Hales has recourse to subtilized aerian principles, which seem too thin to be grasped ; Becher, Stahl, and Henckel to iron or copper; and Pott to the phlogiston, in order to account for the phenomenon in question. After these comes Count Mouroux *, who, by a great number of experiments, has undertaken to prove, that flowers contain a fixed colouring PRINCIPLE, which exists even in the ashes to which they are reduced, and communicates to the vitrifications in which these ashes are employed, the colour of the respective flower, and of all the other parts of the plant, But after him comes M. ACHARD, who repeated all his experiments with the most curious attention, and the results he ob. tained from them were quite contrary to those of Count Mou.
The detail of these experiments, as they were made by M. ACHARD, is exceedingly interesting. This ingenious Academician could never find the least resemblance or analogy be. tween the colour of the vegetable subitance before its incineration, and that of the glass into whose compofition its alhes entered as an ingredient. But if he pulls down an hypothefis built upon ill-conducted experiments, he means to eftablith ano. ther upon more solid foundations : in the second Part of this
His Memoir entitled- A Physico-chemical Examination of ihe Colours of Flowers, and of some o:her vigeialle Subsiances, is inderted in she 5th volume of the Misceilanea Taurinentia,
Memoir, as yet unpublished, he designs to Thew, that the colours of flowers and vegetables, in general, proceed only from the combination of their constituent parts, and from their degree of fermentation, which, according as it varies, produces, of neceffity, a difference in the arrangement of the parts of vegetables :-hence our Author will be led to explain the cause of the changes which the absence or presence of light produces in the colour of vegetables and of other natural bodies.
Memoir. Concerning the Measure of the Salubrity of the Air, containing also the Description of two new Eudiometers. By M. ACHARD. It appears from the accurate experiments and the important discoveries of Dr. Priestley, that the principal use of the air, in respiration, is its discharging the lungs of the phlogiston; so that when the air is saturated with phlogiston, and consequently cannot charge itself with a larger quantity, it becomes unfit for respiration. The less, therefore, that the air is charged with phlogiston, the fitter will it be for respiration; and proportionably more wholesome; and the eudiometers are defigned to ascertain the degree of falubrity that arises from the greater or lefser quantity of phlogiston, with which the air is charged. The eudiometers of Landriani and Magellan are ingeniously constructed; but the employment of them requires preparations which cannot be made every where; besides, a portable instrument of this kind, which, by an easy operation, can enable us to determine the degree of the phlogistication of the air in any place whatever, is an object of consequence. This circumstance gives a peculiar advantage to the invention of our Academician; for a particular descriptive account of whose eu. diometers, which would be scarcely intelligible without a fight of the plates, we must refer the curious to the Memoir itself, and the figures which accompany it.
Memoir. Concerning the Cause of the Asphyxia, and the properest Remedy for that Disorder. By M. ACHARD. As the re1piration of mephitic vapours is the circumftance that produces the asphyxia, an examination of the cause that renders these vapours noxious will naturally lead to the true source of this dif. order. The observations and experiments, made by this indefatigable Academician, on rabbits, finches, cats, and other animals, prove, ift,-That it is to the phlogiston with which mephitic vapours are charged that we must attribute their noxious qualities--2dly, That the phlogiston, which exhales from the lungs, and is obstructed in its passage, produces the asphyxia3dly, That the accumulation of phlogiston in the lungs is the cause of the numbness in the nerves, and of the suspension of respiration during the asphyxia - 4thly, That of all the remedies hitherto employed against this disorder, the immiffion of dephlo
gisticated air is that which promises the most success, because it attacks the evil in its principle and cause.- Our Author's apparatus for transmitting this air into the lungs is well contrived.
MATHEMATICS. Memoir. Concerning the Determination of the Orbits of Comets after three Observations. By M. DE LA GRANGE, Two Memoirs. This celebrated Academician analises the different methods, that have been hitherto proposed, of resolving the problem here mentioned. Sir Isaac Newton was the first who attempted it ; but the folutions which he left behind him were imperfect, and those who succeeded him in the fame undertak. ing did little more than diversify and reduce to a greater fimplicity the methods pointed out by him, without rendering them more exact or commodious for practice. Our Author exposes the defects of all these methods; Thews, that the problem can only be solved by approximation, and points out the manner of solving it in this way.
Memoir. Concerning the Theory of Telescopes. By the fame. The general canons to which Messrs. Cotes and Euler attempted to reduce the theory of telescopes, are here approximated and compared together, by M. LE GRANGE, and are improved by new and interesting researches, which tend to reduce this theory to a greater degree of fimplicity.
Historical and Astronomical Inquiries concerning the Polar Star, and the Constellations that are the nearest to the Poles. By M. JOHN BERNOUILLI. Three Memoirs.
Inquiries concerning the Method of finding directly the Equation of Time. By M. Schulze.
SPECULATIVE PHILOSOPHY. Inquiries concerning the Unities of Nature. By M. BeGUELIN. First Memoir. We have already seen where all the researches of this kind terminate, or rather we have feen that they do not terminate at all-for, instead of coming at the real elements of bodies, they only arrive at the atoms of Leucippus, which come fhort of the mark, or the ideal monades of Leibnitz, which go beyond it, and like the arrow in the Æneid, vanish into air. Presenting to us these old systems, with new names, and some new modifications, they make us think, that we are getting on towards the principles of things ; whereas we remain Itill pretty much in the same place. There is no guide whose penetration and metaphysical talents promise fairer to bring us some steps nearer to the fountain-head than those of M. BEGUELIN: and certainly there is an uncommon degree of acuteness in the Memoir now before us.
By the Unities of Nature, Mr. B. understands neither abstract unities, nor the physical, individual beings, which are the obe jects of our senses, but all those primitive beings, whose organiAPP. Rev. Vol. Ixiv.
zation is indestructible, though susceptible of different modifica. tions, by its own powers, and those of other organized beings. In a word, every unity of nature is a machine, immediately created by the Deity, according to our Academician; and thug we think that he has posted himielf between the Monadifts and the Atomists. How long he will maintain this post, we cannot tell ; ---We do not mean either to interrupt him in the poffeffion of it, or to share it with him. Bui there is something so mafterly and ingenious in his manner of fortifying and defending it, that what he has said may be read with profit, though we neither adopt nor reject his hypothesis. 'It is certain, that ihefe organized unities cannot be objects of observation. It cannot, however, be faid, on the other hand, that their existence is impoffible ; and this is the only conceflion which our Author requires at his setting out in this dark and intricate discussion. Indeed, analogy gives him a full right to this conceffion, at least; fince, as he observes, all individual beings are organized even in their smallest particles, as far as the eye, aided by microscopes, can carry its inspection. It is probable, says he, that this organization goes much farther than we can fee; and that, at length, the decomposition of secondary machines must be resolved into primitive ones, whose organization is the immediate work of the Creator, and which are, consequently, true elements, the real unities of nature; beyond which analysis cannot go.
This hypothefis furnishes Mr. B. with solutions of some of the most difficult questions that have hitherto divided the metaphysicians. Eleven of the feare amply discussed in this first Memoir. They are as follows: 1. Is matter infinitely divisible, and in reality infinitely divided ? ---2. Äre organical beings infinitely subdivisible and infinitely subdivided? The Reader may judge of Mr. B.'s manner of answering these questions by the following judicious observation : Infinity, whether of nuniber or space, is a conception merely geometrical; it is an imaginary notion ; and it we consider it otherwife than as the expreffion of a term or limit to which our narrow understanding cannot reach, it is a palpable contradiction, fince it fupposes and annihilates limits at the same time, This thews, that infinite has no fort of relation to created substances, which are effentially finite. An important truth !-3. Does not each unity of nature comprehend an infinity of different parts? No-for very fatisfactory rearons alleged in the answer to the preceding question-4 Is not each part of an organised primitive being, itself an organised being, till more simple, and so on, without end? No-for then the organised primitive being would be no longer primitive; or, in other words, it would not be what it is. This queftion can only be resolved by banithing from real and finite veings the here improper and contradictory idea of infinity.-5. Are not all the parts of primi,
tive unities composed originally of parts perfectly similar and homogeneous ? The discussion of this question (lays our Author) is of no moment; it is enough to know, that each part has its peculiar nature, its distinctive properties, its aptitude to the uses it is designed to serve.-6. Are the last or smallest parts conceivable of the primitive unity material or not? If (says Mr. B.) you understand by matter, a homogeneous mass, which is only extended and impenetrable, without any other property or quality whatever, then, neither the primitive unities, nor their parts, are material. These unities have, indeed, extension, because their parts are disa tinct; and impenetrability, because two or more of these parts cannot occupy the same place; but as they come from the hand of the Creator, organised, endowed with an active power, and possessed of all the qualities that are requisite to produce the fucceflive effects which result from their nature, the idea of mere matter, as above defined, is not applicable to them. The entire machine, conceived in the Divine Mind, must have received at once its existence by a single act, and thus its nature spurns analytical investigation. The primitive unity does not resemble Pygmalion's ftatue, whose compofition was effectuated by repeated strokes of the chissel on a rude and shapeless mass of marble; it rather resembles the form of Minerva, who issued forth, instantaneously, with all her armour, from the brain of . Jupiter. If this be true with respect to the primitive unities, it is equally applicable to all their parts. -7. Are the last or smalles parts of the unities of nature without size, extension, or figure? They are the elements of lize, extention, and figure; as, in arithmetic, unity is not number, but the element of all numbers whatever. See the Memoir.
See the Mernoir.-- 8. Might not the Deity have created the simple, elementary parts of the unities, and deduced from them these primitive unities by some general laws of nature? What the Deity could or could not do, our Author thinks it rath in us to determine; he, however, modestly puts a negative upon the question, and gives his reasons, for which we refer to the Memoir, as (contrary to what usually happens) we are fomewhat in haste.-9. To have recourse to the IMMEDIATE CREATION of the unities of nature, is not this cutting the knot, instead of loosing it? No--for in all investigations of a cosmological nature we must come, at last, to immediate creation.-10. Does not the analysis of compound beings lead us more naturally to the monades of Leibnitz, or the simple elements of Wolf, than to the primitive unities or automata of nature? No-and, hypothesis for hypothesis, we think that of our Academician preferable to those of the two great German birds of Minerva; fince on his hypothefis the corporeal universe has a true and real existence, conformable to the reports of our senses and feelings, and is noc a mere ideal phenomenon, as it must be in the systems of Leib