The Copernican system was first publicly defended in England, by Dr. Wilkins, in 1660; in France, by Gassendi, the son of a peasant in Provence, who published many valuable works on Philosophy. He was born in 1592, and died in 1655. He was violently opposed by Morin, a famous astrologer. Descartes, descended from a noble family, the son of a counsellor of Brittany, in France, born at Haye, in Tourraine, 31st of March, 1596, early distinguished himself by his knowledge in algebra and geometry. He attacked and overturned the philosophy of Aristotle, in his own country. He attempted to establish certain principles, which, though founded in theory, he took for granted, by which he accounted for all appearances. Like Mochus and Democritus, he imagined all space to be filled with corpuscules, or atoms, in continual agitation, and denied the possibility of a vacuum. He explained everything by supposing vortices, or motions round a centre, according to the opinions of Democritus, and thus discovered the centrifugal force in the circular motion of the planets. But the system of Descartes not being founded on facts or experiments, did not subsist long: although at first it had many followers. His astronomical opinions were much the same with those of Copernicus. Although the lively notions of Descartes led him into error, yet his exalted views greatly contributed to the improvement of science. Men were led to observation and experiments, in order to overturn his system, and astronomy was cultivated by persons of ability; viz., Bouillard, at Paris; Ward, at Oxford, 1653; and by Helvelius, at Dantzic, 1643, who constructed a fine observatory, and collected a great many facts by his long assiduous observation, for fifty years, during which he made many discoveries concerning the planets, fixed stars, and particularly comets. Colbert, in the name of Louis XIV., sent him a sum of money and a pension. Hevelius published a catalogue of fixed stars, entitled, “Firmamentum Sobieskianum,” dedicated to John Sobieski, King of Poland, at that time justly famous for having raised the siege of Vienna, when attacked by the Turks, 1683. In honour of whom Helvelius formed a new constellation between Antinonus and Serpenterius, called _Sobieski’s Shield_. But the most distinguished astronomer of that time was Christian Huygens, son to the secretary of the Prince of Orange, born at the Hague, 14th of April, 1629, and educated at Leyden, under Schooten, the commentator on Descartes,--famous for the application of pendulums to clocks and springs to watches, for the improvement of telescopes and microscopes, and for the great discoveries he made, in consequence of these improvements in astronomy. The establishment of academies, or societies, at this time, contributed greatly to the advancement of science.