tion were almost entirely neglected. - About the fame 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 Chrift. 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 facred 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 luftre of his reputation than his elements of geometry, are not omitted by M. Bailly, nor even the jargon of the Egyptian conjurer Manethon, whose work belongs rather to the vifionary sphere of divination and astrology, than to the class of astronomical productions.

Our Author does justice in this hiftory 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 earth; 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 fun from the earth, which he estimated at 804,000,000 stadia, is exactly conformable to the distance affigned by Meffrs. 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 1672, and at Amsterdam in 1703. Archimedes, the contemporary of Eratolthenes, and the Newton of the Grecian school, deserved a place among the most celebrated astronomers by his curious observation of the sun's diameter, and those 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 affemblage of the various circles of the sphere, seems to have been pretty much of the fame nature with our armillary sphere.

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the the planets. M. BAILLY mentions his invention of the Epicycles, not only with indulgence, but even with commendation, fince at that early period it accounted for all the phenomena, and must be allowed to be ingenious, notwithstanding the contemptuous manner in which it has been rejected in modern

times.

In the second book our Author treats of the instruments invented by the first Alexandrian school, for the improvement of astronomical science.

Astronomical observations were made with increasing degrees of accuracy, until the time of Hipparchus, whom our Author calls the patriarch of astronomy, and whom Pliny denominated the confident of nature. This great man, whose history, genius, and improvements of the science now under confideration, form the subject of the third book, flourished under Ptolomy Philometor a hundred and thirty years before Christ, and treated astronomy with a philosophical spirit unknown before his time. He considered that sublime science under a general point of view, examined the received opinions, passed in review the truths that had been discovered, and pointed out the method of reducing them so far into a system, as to connect them with each other. The Chaldean doctrine, which was an unphilosophical medley, made up of the result of observation and the suggestions of credulity and superftition, was established in the Alexandrian school before he arose: but he treated the determinations of the Chaldeans as Descartes did the systems of the scholastics.-Our Author enters into a long, circumstantial, and interesting detail of the labours and discoveries of this celebrated astronomer, who perceived the inequality of the fun, expressed it in tables, invented the equation of time, the parallax, and the measure of distances; who undertook and executed a true description of the heavens, and laid the folid foundations of geographical and trigonometrical science. We cannot follow our learned Author in his ample account of these discoveries: the only thing that we can present to our Readers on this and all the other articles, is such a flight sketch of his narration as may indicate the entertainment and instruction which they may expect in perusing this excellent history.

Three hundred years passed between Hipparchus and Ptolomy, who flourished at Alexandria, in the second century, under the empire of Adrian and Marcus Antoninus. This great man was the last ornament of the Alexandrian school. He collected all the obfervations that had been made before his time, more especially those of Hipparchus and Poffidonius (the only fucceflor of Hipparchus who had any confiderable reputation), and was for a course of ages at the very fummit of aftronomical fame, till Copernicus removed him on a sudden from thence,

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and took his place, which he is likely to keep as long as fun and moon thall endure. Ptolomy collected the refult of his labours and aftronomical observations in an immortal work, intitled the Almagest, which was to furnish astronomers of future times with the means of furpaffing their ancient guides. This work forms the communication between ancient and modern aftronomy, and contains methods, or the germs of methods (to use our Author's expreffion), which are still employed in our times. The account of this great aftronomer is the fubject of the fourth and fifth books of this hiftory.

In the fixth and feventh, M. BAILLY treats of the aftronomical knowledge of the Arabians, the modern Tartars, the Chinese, and even of fome of the American tribes or nations. As to the Arabians, he paints their fanatical pafion for conquest, and the devaftations that accompanied it, in the most striking manner: he represents these booted disciples of Mahomet, ruthing into Egypt, making themselves matters of Alexandria, dettroying that famous library, which was (if we may use that expreffion) the focus, where all the rays of icence and learning, that proceeded from all parts of the globe, were united and collected:-he describes them heating their floves with the precious treafures contained in that immenie collection; he reprefents fciences and letters as perishing in the ruins of that library, and the Alexandrian fchool (which had been founded 280 years before the Chriftian æra) expiring in the middle of the seventh century. M. Bailly, indeed, turns the medal, and presents the Arabians in an afpect that, at leaff, makes fone amends for their depredations: he tells us wittily, that barbarians are like children, who destroy whatever comes into their hands, and foon after regret what they have deftroyed, cry for it, and would be glad to have it back again. Thus, ays be, the Arabians, after having burned the library, and dripered the philofophers of the Alexandrian school, looked earreilly for the light, which they them elves had extinguithed, and from the athes, which their odious barbarity had accumulated, and were pleking out eagerly, before the century ended, the precious remains of erudition and cience that had escaped the fames. But though he allows them the honour of fome knowledge and fome difcoveries, fuch as that of the motion of the fun's apogee, the knowledge of the pendaum, and come other uferal chervations; wet upon the whole he confiders them, as only commendable for having preferved the remains of the facred fire, which they had, at first, attempted to extinguits and reprefonts them as more formed for judiciary anthogy base for Altronomical fcience.

21 are fight Suok M. BAILLY follows astronomy into Euame. A er saving contemplated it in its imagined grandeur magined by this chimerical hypothetis of the Atlantis) in

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the early ages, and amidst the changes and shocks it received, from the revolutions and convulfions of nations, as well as in the improvements and advantages it acquired from the protection of learned princes and the labours of men of genius, he considers the noble edifice as indebted for the completion of its grandeur to Europe. Its grandeur, indeed, is not yet completed; but great things have been done, and are still doing for this purpose. Italy and Germany began the work: England and France have accelerated its construction; at this very moment all nations seem to join hands to raise the building, and it is difficult to say (we use our Author's words) where the summit of its majestic grandeur will stop. In this book M. BAILLY shews the obligations which astronomical science has, in this part of the globe, to the talents, genius, researches and penetration of Purbach, Regiomontanus, and Waltherus. The first of these three famous astronomers composed a theory of the planets, in which he endeavours to correct the system of Ptolomy. John Muller (generally known under the name of Regiomontanus, which is the Latin word for Koningsberg, the place of his nativity) was the disciple of Purbach, and furpassed his master. He is considered as the inventor of the Ephemerides, and in the year 1474, Pope Sixtus IV, having conceived a design of reforming the calendar, fent for him, as the propereft person to execute that design, and made him Archbishop of Ratisbon. Two years before this, in 1472, he observed a comet, which was the first that was noticed in Europe. He was intimately perfuaded of the motion of the earth, and would perhaps have anticipated Copernicus in the reformation of astronomy, and the re-invention of the true system of the world, had he not been carried off by the plague, at the age of forty. Waltherus was the friend of Muller, who had assisted him by his liberal contributions to the expence that he was at in the construction of astronomical instruments, and obtained much instruction from his conversation while he lived, and from his papers after his death. He was suspected of having published some of Muller's productions as his own; it cannot, however, be denied, that he was a man of sagacity and genius, of which his use of clocks, for the measure of time in astronomical observations, is an evident proof.

The grand revolution that happened in the history of astronomy from the rife of Copernicus, towards the conclusion of the fifteenth century, to the time of Ticho-Brahe, who was born in the midst of the fixteenth, employs our Author in the ninth and tenth books of this hiftory, which conclude the first volume. In such a sublime flight as that of Copernicus, who forbids us to believe the motion that we fee, and engages us to confider as certain, that of which we have not the least perception or feeling; who represents the fun and the stars as motionless, and our heavy globe

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globe whirling itself with rapidity about the great source of light, who could have imagined, that he had hit upon the truth, and found out the real system of the universe? His discovery became a fundamental truth in aftronomy, and he treated that science with the creating spirit of a philosopher and a legislator. He did not, however, bring the art of observing to perfection, an art which requires rather patience and sagacity than invention and genius.

The science of astronomy, notwithstanding this noble difcovery, ftood in need of facts and observations; and these were furnished in a rich abundance by that spirit of affiduity, curiosity, and detail, that diftinguished Ticho-Brahe, whom the impulfion of genius and nature rendered an astronomer; while an eclipse of the fun in 1560 gave the word. The labours of Ticho-Brahe are well known: our Author unfolds, in an ample narration, their nature and their merit: he does justice to this great man by acknowledging, that his system is not incompatible with mathematical principles, and even that it corrects with dexterity the absurdities that the hypothesis of Ptolomy had introduced into the wife arrangements of the universe. But he attacks the system of the Danish astronomer upon the principles of natural philofophy, and that victoriously:-he blames him for not having adopted the system of Copernicus, and for running the risk (by fubftituting another in its place) of plunging the truth anew in the very abyss from which it so lately emerged.

It is a mortifying instance of the infirmity of human nature, even in its best appearances, that the greatest part of the eminent astronomers already mentioned, were tainted with the superstitrous nonsense of judicial astrology. It was not only the Arabians who gave into this folly, it was not only an Abu-elMaafar, who believed, amidst the noblest efforts of learning and genius, that the Jewish, Egyptian, Turkish, and Chriftian reLigions were derived, respectively, from the conjunction of certain planets: but Hipparchus, Ptolomy, Purbach, Muller, Ticho-Brahe, and many others laboured under a similar folly; and this gives our Author occasion to say several good things on this disease of the human imagination, in an excellent differtation on aftrology,

This volume is terminated by several instructive illustrations relative to astronomical science, a curious lift of the oriental astronomical manuscripts, that are to be found in some of the principal libraries of Europe, and an indication of the works of the principal astronomers: the whole accompanied with thirteen plates accurately engraven.

Kepler feems to be the astronomical hero of our Author. He was a native of Wirtemberg, and was born in 1571. According to M. BAILLY, Kepler was the true founder of modern astronomy,