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nor arguments sufficient to prove that the soul or animated molecule can have no feeling or perception without the affistance of the body. When therefore he maintains this, his third proposition against the Platonists (who considered the animal body as the prison of the soul, which restrains its operations, retards its flight to perfection, and renders dim and dubious its view of truth, and who regarded the separation as the moment that opened light and truth upon it in their purity), he has no means of defence but the fact above mentioned, and conjectures.

His conjectures are, indeed, ingenious, and if they do not administer either evidence, or a luminous probability with respect to what he designs to prove, yet they unfold by the way interesting views of the operations of nature, and the supreme wisdom by which they are directed. They are drawn from analogy, but are of too fubtile and intricate a nature not to lose what perspicuity they have in an abridgment;-we therefore refer the metaphysical reader to the memoir itself.

If the fupposition of the animated molecule's lofing all its consciousness and fenfibility by its feparation from the animal body appears uncomfortable, our Academician revives our hopes of a new life, in his fourth propofition, which is, that the animated molecule, when separated from the animal body, is not confounded and mingled with the general mass of matter, but follows the particular laws prescribed to the species to which it belongs. In the illustration of this proposition, our Author observes, among other things, that in the destruction of bodies produced by natural causes, the decomposition is effected in such a manner, that the elementary parts of the diffolved body are separated from each other, and return each to the general mass of the substances of its kind, in order to be employed anew in a manner conformable to their destination. This fact we daily observe in the decomposition of bodies compounded of air, water, and earth. When they are dissolved, either by fire or putrefaction, the particles of air, water, and earth, are reunited to their respective elements; and by this admirable operation of nature there are always materials for new productions.Now if such (savs our Author) is the course and procedure of nature in the destruction of animal bodies, we may conclude by induction and analogy, that animated molecules are subjected tó a similar law, and that after the destruction of the bodies to which they were united, they repair to the general assemblage of their species, and remain there until the time comes which is fixed for their vivifying new bodies. - It was thus, probably, continues our Academician, that they found their way to ail union with the animal bodies, now living; it is this hypothesis alone (says he) that can explain the union between foul and body:

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for we must either admit continual miracles, or suppose, that fouls unite themselves to animal bodies by natural means, by laws which result from the specific qualities of the animal body and those of the animated molecule.-This is an ingenious dress given to the great stoical revolution that renews nature at certain fixed periods. Be that as it may-the Author proves by the existence of monsters, which arise from accidental causes, modifying the formation of natural productions, that the formation of animal bodies is produced by natural means

under the empire of providence, and not by the immediate operations of the deity, which would have prevented the influence of these causes. But the influence of these accidental causes is much less frequent in the Animal than in the Mineral and Vegetable kingdoms; and this furnishes our Author with ä farther argument in favour of the preservation of the animated molecule.

From these general considerations, in favour of his fourth proposition, M. SULZER thinks it necessary to proceed to others more particular and more analogous to his subject.He is persuaded that the primitive organized germs, froń whence animals are produced, exist since the commencement of the world, are diffused throughout the globe, are preserved amidst the revolutions to which all things here below are exposed, and are developed, every one in its feason, according to regular and permanent laws.

As this fact is analogous to what our Academician has maintained concerning animated molecules, he proposes in a following memoir to exhibit the reasons which have induced him to adopt the hypothesis of pre-existent germs, on which modern philosophers differ so much, To treat this important subject with the attention it requires and deferves--he proposes,

First, To prove that the formation of organized bodies, such as plants and animals, could not be effected by laws merely mechanical or physical, and that therefore the hypothesis of the epigenesis is without any foundation : from whence it will appear, that the primitive germs of plants and animals preexist in nature, as the elementary substances, above mentioned, exist previously to the formation of bodies in general.

Secondly, To Thew that the hypothesis of some modern philosophers, who suppose these germs inclosed one within the other, is destitute of all probability, and contrary to palpable facts : from whence he concludes that these germs are dispersed and distributed throughout all nature, in the same manner as other elementary subitances.

Thirdly, To prove that there are laws prescribed to the germs of organized bodies, by which the germ of each plant

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and animat actually existing must bave been conveyed to the place where it has been developed.

From all which it will appear, that there is continually carried on in nature a process, fimilar and analagous to that which he supposes with respect to the animated molecule, before its union with the animal body, and after its separation from it by death,

We fear that this separation has hindered our learned Academician from executing this plan: if not, we shall give an account of it when it appears.

Philosophical Reflexions concerning Certainty. By M. DE BEAUSOBRE. There are several sensible things in this piece. It is upon the whole judicious and solid, and does honour to its author ; but there is nothing in it that requires particular notice.

Concerning the Influence of Natural Causes on the Mind of Man. By Dom. PERNETY.-An account of this ingenious memoir, as also of those that belong to the class of the Belles Lettres, will be given in our next Appendix.

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VI. Histoire de l'Astronomie Moderne depuis la Fondation de l'Ecole d'Alex.

andrie jusqu'à l'Epoque de 1730.-A History of Modern Afronomy, from the Foundation of the Alexandrian School, to the Epocha of 1730. By M. BAILLY, of the Academy of Sciences at Paris. 2 Vols. 4to. With Cuts. 1779. T is always with pleasure that we review the productions

of this agreeable, acute, and truly learned Philosopher, who is inftructive and interesting even when he roams through the fields of fancy; who dreams like a man of genius; but who is peculiarly worthy of all our attention, when he walks in the real paths of historical fact and philosophic science. In this respectable point of view does he appear in the incomparable work before us, where we find the same vaft erudition, the fame charms of eloquence, the same elegance and brilliancy of style, that have so much distinguished his former productions.

The parts of this work, which are purely astronomical, and those discussions which are not immediately relative to the history and progress of that noble science, the reader muft peruse in the work itself; wherein he will find profound researches and calculations, which would lose their perspicuity, and perhaps their precision, in an abridgment. We therefore confine ourselves to the historical, which is the principal and the essential part of this work, and which will certainly be moft inftructive and entertaining to the generality of our Readers.

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Nor has M. BAILLY loft fight of the less learned class of readers in the composition of this hiftory; he has admitted into it no more of the mathematical part of astronomy than was necessary to shew the means by which discoveries were made in that science.

Our Author is less bewildered in following the historical thread of this science, in modern tiines, where the path is beaten, where the facts are ascertained, and the dates are incontestible, than he was, when he wandered in the devious wilds of ancient philosophical history, in order to view the genuine aspects of astronomical science, in the early ages. And though we admired the ingenious conjectures, by which he directed his course, for want of surer guides, and the almost magic power, with which he has thrown fathes of light upon the moft dubious objects, yet these flashes gave but a momentary evidence: we were ftill falling back into doubts and difficulties; and we are now very glad to follow him through a tract of time, where the road is as plain and luminous as the objects it represents are interesting and sublime.

The first volume of this excellent work is divided into ten books. The first five exhibit to us, fucceffively, all that is known of the school of Alexandria and of the astronomers who preceded Hipparchus. This school, which was founded by Ptolemy Philadelphus, 'subasted near ten centuries. Though it was erected in Egypt, and that at a time when the sciences, encouraged by the munificence of that prince, and promoted by other concurring circumstances, flourished anew, yet it derived its principal lustre from the Greeks, who seemed destined by nature to bring to perfection what others had invented, and who removed from astronomical science the veil with which it had been covered by the Egyptian priests. It is certain (we follow the relation of M. BAILLY) that aftronomy appeared under a new aspect at this period. Observations of the heavenly bodies were made with instruments, susceptible of a certain degree of precision; hypotheses were formed to explain the motions of the planets; the progressive motions of the stars were observed ; their places were determined ; and all these improvements were inserted by Hipparchus in a catalogue, that they might furnish points of comparison to future ages.

Timocharis and Aristillus are the first astronomical observers we meet with in the school of Alexandria under Ptolemy Soter, about three hundred years before Christ. Others there may have been that Hipparchus may have omitted. His work, entitled Almagest, or the Great Work, which contains all the attempts and improvements in astronomical science that had been made in the school of Alexandria, was in such high esteem, that the sources from which he had taken his informa

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tion were almost entirely neglected.- About the same time Aratus, the poet, was born at Solis, a town in Cilicia, and was employed by Antigonus, 'king of Macedon, to embellish with the charms of poetry all the branches of astronomy that were then known.

The first astronomer of note, who appeared in the Alexandrian school after these now mentioned, was Aristarchus of Samos, contemporary of Cleanthes, a stoic, who succeeded Zeno, about the 129th Olympiad, or two hundred and fixtyfour years before Christ. This philosopher applied himself to the most important branches of astronomy, and made a judicious choice among the ancient systems; but by adopting the hypothesis of the earth’s motion, he ran counter to an opinion that had been rendered sacred by the lapse of ages, and by the veneration of the multitude; and accordingly, like Galilei, he was accused of impiety, for having disturbed the repose of Vesta, or the earth, and of the houshold gods, who made a part of her retinue.-The phenomena of Euclid, which contributed much less to the lustre of his reputation than his elements of geometry, are not omitted by M. Bailly, nor even the jargon of the Egyptian conjurer Manethon, whole work belongs rather to the vifiomary sphere of divination and astrology, than to the class of astronomical productions.

Our Author does justice in this history to the celebrated librarian of Alexandria, Eratosthenes, who was called the furveyor of the universe, the cosmographer, and the second Plato. He was the first, in effect, who attempted to measure the ear:h; and the method he invented for this purpose has rendered his name immortal. He was the inventor of the astrolabe *, with which he undertook to measure the obliquity of the ecliptic; and it is fingularly remarkable, that the distance of the sun from the earth, which he estimated at 804,000,000 ftadia, is exactly conformable to the distance assigned by Messrs. de Caffini and the Abbé de la Caille. The works that remain of this excellent poet, grammarian, mathematician, and astronomer, were printed in an octavo volume, at Oxford, in the year 1572, and at Amsterdam in 1703. Archimedes, the contemporary of Eratolthenes, and the Newton of the Grecian school, delerved a place among the most celebrated astronomers by his curious observation of the sun's diameter, and these which he made on the solstices; and Apollonius Pergaus, about the same time, acquired a high degree of fame, by his being the first who attempted to explain the stations and retrogradations of

• The astrolabe, which was anciently used for an assemblage of the various circles of ihe sphere, seems to have been pretty much of the same nature with our armillary sphere.

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