BAILLY, Jean Sylvain, a celebrated philosopher and astronomer, was born at Paris on the 15th of September 1736. He was .originally intended for the professicn of painting, which his family had pursued for several generations, and he even had made some progress in the art. But the bias of his mind leaned too much to literary pursuits, especially to poetry and works of imagination, to permit him to give that application which is necessary to secure success and eminence in any profession.

The friends of Bailly, who had witnessed the early dawn of his genius, saw that it was alike fitted to appear with advantage in the study of polite literature, or to shine in the walks of science; and they recommended the latter chiefly to his attention. His acquaintance with Lacaille, the celebrated geometer, commenced; and this at once decided the object of his studies, which were now almost entirely devoted to scientific investigations. The first of his labours was a calculation of the comet which appeared in the year 1759. In January 1763 he was admitted a member of the Academy of Sciences; and in the same year he published a reduction of the observations made by Lacaille in 1760 and 1761 on the zodiacal stars: an elaborate compilation, and of very extensive utility. His attention was afterwards directed to the consideration of the theory of Jupiter’s satellites. Lagrange, who now promised[7:4:290] to become the first mathematician in Europe, was the formidable rival of Bailly in the competition for this prize question in 1764. The results of his investigations were collected into a treatise, which also contained the history of that part of astronomy, and were published in 1766. In 1771 appeared his interesting and important memoir on the Light of the Satellites, which was marked with a degree of precision and accuracy till that time unknown in the observations of their eclipses.

The studies of Bailly were not entirely limited to the cultivation of abstract science, nor to profound physical speculations; his genius shone with equal lustre in those departments of literature which require a discrimination of character, and no common powers of eloquence, in order to attain excellence. His Eloges on Charles V., Corneille, Leibnitz, Molière, Cook, Lacaille, and Gresset, were universally admired as valuable specimens of fine writing, and they added much to his reputation. The distinguished place of secretary of the Academy of Sciences became vacant in 1771; and, supported by the patronage and influence of Buffon, he offered himself a candidate. But, in this instance, he was unsuccessful. Condorcet, then rising into reputation, and supported by the active influence of D’Alembert, was preferred to the office.

In the year 1775 he published at Paris the first volume of his great work, the History of Astronomy, containing the history of astronomy from its origin to the foundation of the Alexandrian School; and this was followed by three volumes on the history of modern astronomy, published between 1776 and 1783. This work, which is of inestimable value, is distinguished alike for animated description, luminous narration, and interesting detail. Besides, he published, in 1777, a work entitled Letters on the Origin of the Sciences, and of the People of Asia; and this was followed by another series of Letters on the Atlantis of Plato, and the Ancient History of Asia, as a continuation of the same work. These volumes were addressed to Voltaire, with whom he had commenced an ingenious correspondence and discussion on this curious subject. The coincidence of his opinions with those of Buffon in points respecting some of the favourite theories of the latter, brought on an intimate acquaintance and close friendship with that celebrated naturalist; which, however, declined and was entirely dissolved, in consequence of the opposition which Bailly made to the election of the Abbé Maury into the French Academy. Bailly had been chosen secretary of the academy in 1784; and in the following year he was admitted into the Academy of Inscriptions and Belles Lettres. This was the only instance, since the time of Fontenelle, of the same person being at once a member of all the three academies.

In the year 1784 he was nominated one of the commission to investigate the nature of the animal magnetism of Mesmer; and he drew up a very elegant report, which was presented to the academy of Sciences. This report, which was soon afterwards translated into English, not only marked the acuteness and discernment of the author, and contained the most satisfactory and decisive evidence with regard to its object, but it may be held up as an excellent model of imitation for those who are engaged in similar investigations. In developing the physical effects produced by moral causes, it is of the greatest value; and it is particularly interesting when we consider the political influence which causes of this nature have exerted on the general opinions of society, and even on the destiny of nations.

In 1787 he published, in one volume 4to, the History of Indian and Oriental Astronomy ļ a work of great erudition and ability, but in which he is thought to have made some erroneous calculations, and to have overrated the antiquity of the Indian observations.

Hitherto we have contemplated Bailly in the shades of retirement, and in the calm undisturbed retreats of philo- ' sophy, employing the energy of a vigorous and comprehensive mind in the profound researches of physical truth. We are now to follow him in his political career, and to behold him struggling with the adverse interests of factions, and contending with the unbridled fury of a lawless mob, in defence of the rights of a people whose minds were not prepared to understand, and whose habits were not yet formed to enjoy, the blessings of rational liberty. He was one of the first and most zealous promoters of the revolution in France; and in the part which he acted in this bloody struggle, he has had the good fortune to be well spoken of by opposite factions. He has never been charged with want of integrity or with selfish designs; but apparently actuated by a misguided zeal, and dazzled with the prospect of freedom which the warmth of his imagination held out, he rashly committed himself in a cause which, as he had espoused it with enthusiasm, so he supported it with his utmost exertions. But in that cause he fell a sacrifice to the unrelenting spirit of violence and faction which had been easily roused, but which it was found impossible either to subdue or to regulate. When the states-general of France were assembled in 1789, he was elected a deputy to the tiers-etat, of which he was afterwards chosen president; and when the national assembly had been constituted, he continued in the chair, and officiated as president at the time the king’s proclamation was issued ordering that body to disperse. During the struggle which took place between the national assembly and the court, Bailly was amongst the most forward in asserting those popular rights which were then new in France; and it was he who dictated the famous oath to the members of the tiers-état, by which they pledged themselves “to resist tyrants and tyranny, and never to separate till they had obtained a free constitution.” On the 14th of July following, the day on which the Bastille was stormed and taken by the people, he was appointed mayor of Paris with universal consent. In this high office he is allowed to have acted with great integrity, courage, and moderation, and to have discharged its arduous and sometimes perilous duties in a manner highly honourable to his character. While he held this conspicuous situation, he was instrumental in promoting the various measures by which the popular party at length prevailed over that of the court; for which, as well as for his conduct in other respects, he obtained a high degree of favour among the people. But the tide of public opinion now swelled beyond all bounds; and no restraint could oppose its violent course. The multitude, newly unshackled from the fetters of despotism, greedy of novelty fired with enthusiastic and unsettled notions of freedom, and daily panting for change, would brook no opposition. Bailly, who now perhaps saw when it was too late the general disposition of the people to anarchy, still wished the laws to be respected, and hoped by their vigorous execution to restore and maintain tranquillity. He ordered some deputies from the military insurgents of Nancy to be arrested, and firmly opposed the rash proceedings of Marat and Hebert; he became a member of a less promiscuous club than that of the Jacobins; and he exerted himself strongly to persuade the populace to permit the king and royal family to depart to St Cloud. By these measures, which were little relished by a fickle and infuriated people, he lost their confidence and favour. But what finally destroyed his popularity, was his conduct on the occasion of the tumultuous meeting of the populace on the 17th of July 1791, to demand the abolition of monarchy; for being called by the national assembly to disperse the mob, who had assaulted the soldiery, he ordered [7:4:291]the latter to fire, by which means forty persons were killed and above a hundred wounded. Having thus become obnoxious to the people, whom he had faithfully served, it was no longer desirable for him to hold his charge. He therefore resigned his office at the dissolution of the constituent assembly in the end of the year 1791; and having resumed his philosophical researches, lived for some time in retirement. But the times of bloody proscription approached; and he was doomed to fall a sacrifice to the ferocious vengeance of the plebeian tyrant who now bore unlimited sway. He was accordingly denounced as an enemy to the republic, arrested, and thrown into prison. Arraigned before a sanguinary tribunal, he was summarily condemned to death as a conspirator, and executed the day following, near the spot where he had given the order for the military to fire on the people. On the day of execution, his sufferings, which he bore with the utmost calmness and magnanimity, were studiously protracted. Instead of that sympathy and compassion which even the worst and the lowest criminal often experiences when he is about to expiate his offences with his life, he was treated by an incensed and fanatical populace with the most ignominious indignity and cruelty. He wore the red shirt, or badge of conspiracy, and was placed in a cart with his hands tied behind his back. During the whole time of his progress to the place of execution, the rain poured incessantly on his head. ’ The populace, as he passed, threw mud at him, and cruelly insulted him with every kind of opprobrious language. Arrived at the place of execution, it was found necessary to remove the guillotine from the spot where it had first been erected, to firmer ground. During this time he was forced to get out of the cart, and walk round the field, in order to gratify more fully the implacable and unrelenting malice of the populace. While he was ascending the platform, a spectator who happened to be near him, exclaimed, in a tone of insult, “Bailly, you tremble “Yes,” he instantly replied, “but it is from cold.”

Several works written by Bailly, and found in manuscript, have been published since his death; particularly an Essay on Fables and their History, and Memoirs of a Witness of the Revolution, which come down to October 1789.

In his person Bailly was tall, and of a sedate but striking countenance. He possessed great firmness and decision of character; but in him these qualities were far removed from sullenness or apathy. Few philosophers have been more distinguished in so many various departments of science and literature, or have acquired such deserved reputation. In his public stations, as well as in the retirement of domestic life, his integrity and disinterestedness remained pure and untainted. In the time of his magistracy he spent part of his fortune in relieving the wants of the poor. His wife, whom he married in 1787, survived him. She was the widow of Raymond Gaye, who had been his intimate friend for twenty-five years.