Jean Sylvain Bailly - Biography

Astronomer and politician, born in Paris, France. He studied Halley's comet and the satellites of Jupiter, later writing his great Histoire de l'astronomie (1775–87). As president of the National Assembly and Mayor of Paris (1789–91) during the Revolution in 1789, he conducted himself with great integrity, but lost his popularity by allowing the National Guard to fire on anti-royalist crowds. He withdrew from public affairs but was guillotined.

Jean-Sylvain Bailly (September 15, 1736–November 12, 1793) was a French astronomer and orator, one of the leaders of the early part of the French Revolution.

Biography

Born at Paris, he was originally intended for the profession of a painter, but preferred writing tragedies, until attracted to science by the influence of Nicolas de Lacaille. His Essai sur la theorie des satellites de Jupiter (Essay on the theory of the satellites of Jupiter, 1766), an expansion of a memoir presented to the Academy in 1763, showed much original power; and it was followed up in 1771 by a noteworthy dissertation Sur les inegalites de la lumiere des satellites de Jupiter (On the inequalities of light of the satellites of Jupiter). he was admitted to the Académie française on February 26, 1784, and to the Académie des Inscriptions in 1785, when Bernard le Bovier de Fontenelle's simultaneous membership of all three Academies was renewed in him. From then on, he devoted himself to the history of science, publishing successively: Histoire de l'astronomie ancienne (A history of ancient astronomy, 1775); Histoire de l'astronomie moderne (A history of modern astronomy, 3 vols., 1779-1782); and Traite de l'astronomie indienne et orientale (A treatise on Indian and Oriental astronomy, 1787). Elected deputy from Paris to the Estates-General, he was elected president of the Third Estate (May 5, 1789), led the famous proceedings in the Tennis Court(June 20), and - immediately after the storming of the Bastille - became the first mayor of Paris under the newly adopted system of the Commune (July 15, 1789 to November 16, 1791). The dispersal by the National Guard, under his orders, of the riotous assembly in the Champ de Mars (July 17, 1791) made him unpopular, and he retired to Nantes, where he composed his Mémoires d'un témoin (published in 3 vols. Late in 1793, Bailly quitted Nantes to join his friend Pierre Simon Laplace at Melun, but was there recognized, arrested and brought (November 10) before the Revolutionary Tribunal at Paris.