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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 aftronomy that were then known.

The firft aftronomer of note, who appeared in the Alexandrian fchool after thefe now mentioned, was Ariftarchus of Samos, contemporary of Cleanthes, a ftoic, who fucceeded Zeno, about the 129th Olympiad, or two hundred and fixtyfour years before Chrift. This philofopher applied himself to the most important branches of aftronomy, and made a judicious choice among the ancient fyftems; but by adopting the hypothefis of the earth's motion, he ran counter to an opinion that had been rendered facred by the lapfe 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 lefs 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, whofe work belongs rather to the vifionary sphere of divination and aftrology, than to the class of aftronomical productions.

Our Author does juftice in this hiftory to the celebrated librarian of Alexandria, Eratosthenes, who was called the furveyor of the univerfe, the cofmographer, and the fecond 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 ftadia, is exactly conformable to the diftance affigned by Meffrs. de Caffini and the Abbé de la Caille. The works that remain of this excellent poet, grammarian, mathematician, and aftronomer, were printed in an octavo volume, at Oxford, in the year 1672, and at Amfterdam in 1703. Archimedes, the contemporary of Eratolthenes, and the Newton of the Grecian fchool, deferved a place among the most celebrated aftronomers by his curious obfervation of the fun's diameter, and those which he made on the folftices; and Apollonius Pergaus, about the fame time, acquired a high degree of fame, by his being the firft who attempted to explain the ftations and retrogradations of

The aftrolabe, which was anciently used for an affemblage of the various circles of the fphere, feems to have been pretty much of the fame nature with our armillary sphere.


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


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

Aftronomical obfervations were made with increafing degrees. of accuracy, until the time of Hipparchus, whom our Author calls the patriarch of aftronomy, and whom Pliny denominated the confident of nature. This great man, whofe hiftory, genius, and improvements of the fcience now under confideration, form the subject of the third book, flourished under Ptolomy Philometor a hundred and thirty years before Chrift, and treated aftronomy with a philofophical fpirit unknown before his time. He confidered that fublime fcience under a general point of view, examined the received opinions, paffed in review the truths that had been discovered, and pointed out the method of reducing them fo far into a fyftem, as to connect them with each other. The Chaldean doctrine, which was an unphilofophical medley, made up of the refult of obfervation and the fuggeftions of credulity and fuperftition, was established in the Alexandrian fchool before he arofe: but he treated the determinations of the Chaldeans as Defcartes did the fyftems of the fcholaftics. -Our Author enters into a long, circumftantial, and interefting detail of the labours and difcoveries of this celebrated aftronomer, 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 true defcription of the heavens, and laid the folid foundations of geographical and trigonometrical fcience. We cannot follow our learned Author in his ample account of these discoveries: the only thing that we can prefent to our Readers on this and all the other articles, is fuch a flight sketch of his narration as may indicate the entertainment and inftruction which they may expect in perufing this excellent hiftory.

Three hundred years paffed between Hipparchus and Ptolomy, who flourished at Alexandria, in the fecond century, under the empire of Adrian and Marcus Antoninus. This great man was the laft ornament of the Alexandrian school. He collected all the obfervations that had been made before his time, more efpecially thofe of Hipparchus and Poffidonius (the only fuccellor of Hipparchus who had any confiderable reputation), and was for a courfe of ages at the very fummit of aftronomical fame, till Copernicus removed him on a fudden from thence,

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and took his place, which he is likely to keep as long as fun and moon fhall endure. Ptolomy collected the refult of his labours and aftronomical obfervations in an immortal work, intitled the Almagest, which was to furnish aftronomers of future times with the means of furpaing their ancient guides. This work forms the communication between ancient and modern aftronomy, and contains methods, or the germs of methods (to ufe our Author's expreffion), which are till 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 pashion for conqueft, and the devaftations that accompanied it, in the most ftriking manner: he reprefents thefe booted difciples of Mahomet, ruthing into Egypt, making themselves matters of Alexandria, deffroying that famous library, which was (if we may ufe 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 defcribes them heating their ftoves with the precious treafures contained in that immente collection; he reprefents fciences and letters as perifhing in the ruins of that library, and the Alexandrian fchool (which had been founded 280 years before the Christian æra) expiring in the middle of the seventh century. M. Bailly, indeed, turns the medal, and prefents the Arabians in an ape that, at leaf, makes me amends for their depredations: he tells us wittily, that barbarians are like children, who deftroy 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, as he, the Arabians, after having burned the library, and dipered the philofophers of the Alexandrian fchool, looked ezreely for the light, which they themselves had extinguished, 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 science that had escaped the fimes. Bet though he allows them the honour of fome knowledge and fome discoveries, fuch as that of the motion of the fun's apogee, the knowledge of the pendulum, and fome other useful obarvations; yet 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 ex ingat, and represents them as more formed for judiciary artising sun for itronomical iclence.

In the gemia book M. BAILLY follows afronomy into Eu

Aler Marring contemplated it in its imagined grandeur margued by the chimerical hypothetis of the Atlantis) in


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 confiders 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 ftill doing for this purpose. Italy and Germany began the work: England and France have accelerated its conftruction; at this very moment all-nations feem to join hands to raise the building, and it is difficult to fay (we use our Author's words) where the fummit of its majestic grandeur will ftop. In this book M. BAILLY fhews the obligations which aftronomical science has, in this part of the globe, to the talents, genius, refearches and penetration of Purbach, Regiomontanus, and Waltherus. The firft of thefe three famous aftronomers compofed a theory of the planets, in which he en❤ deavours to correct the fyftem 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 difciple of Purbach, and furpaffed his mafter. He is confidered 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 defign, and made him Archbishop of Ratifbon. 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 aftronomy, 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 affifted him by his liberal contributions to the expence that he was at in the construction of aftronomical inftruments, and obtained much inftruction from his converfation while he lived, and from his papers after his death. He was fufpected of having publifhed fome of Muller's productions as his own; it cannot, however, be denied, that he was a man of fagacity and genius, of which his ufe of clocks, for the measure of time in aftronomical obfervations, is an evident proof.

The grand revolution that happened in the history of aftronomy from the rife of Copernicus, towards the conclufion 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 fublime 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 leaft perception or feeling; who represents the fun and the ftars as motionless, and our heavy



globe whirling itfelf with rapidity about the great source of light, who could have imagined, that he had hit upon the truth, and found out the real fyftem of the univerfe? His discovery became a fundamental truth in aftronomy, and he treated that fcience with the creating fpirit of a philofopher and a legislator. He did not, however, bring the art of obferving to perfection,—an art which requires rather patience and fagacity than invention and genius.

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The science of aftronomy, notwithstanding this noble difcovery, flood in need of facts and obfervations; and these were furnished in a rich abundance by that fpirit of affiduity, curiofity, and detail, that diftinguifhed Ticho-Brahe, whom the impulfion of genius and nature rendered an aftronomer; while an eclipfe 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 juftice to this great man by acknowledging, that his fyftem is not incompatible with mathematical principles, and even that it corrects with dexterity the abfurdities that the hypothefis of Ptolomy had introduced into the wife arrangements of the univerfe. But he attacks the system of the Danish aftronomer upon the principles of natural philofophy, and that victoriously:-he blames him for not having adopted the fyftem of Copernicus, and for running the risk (by fubftituting another in its place) of plunging the truth anew in the very abyfs from which it fo lately emerged.

It is a mortifying inftance of the infirmity of human nature, even in its best appearances, that the greatest part of the eminent aftronomers already mentioned, were tainted with the superstitious nonfenfe of judicial aftrology. It was not only the Arabians who gave into this folly, it was not only an Abu-elMaafar, who believed, amidst the nobleft efforts of learning and genius, that the Jewish, Egyptian, Turkish, and Christian reLigions were derived, refpectively, from the conjunction of certain planets: but Hipparchus, Ptolomy, Purbach, Muller, Ticho-Brahe, and many others laboured under a fimilar folly; and this gives our Author occafion to fay feveral good things on this difeafe of the human imagination, in an excellent differtation on aftrology,

This volume is terminated by feveral instructive illustrations relative to aftronomical science, a curious lift of the oriental aftronomical manufcripts, that are to be found in fome of the principal libraries of Europe, and an indication of the works of the principal aftronomers: the whole accompanied with thirteen plates accurately engraven.

Kepler feems to be the aftronomical 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 aftro


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