BIOT, JEAN BAPTISTE, a distinguished French physicist and astronomer, was b. at Paris, 21st April, 1774. He at first entered the artillery, but forsook the service for science; and in 1800 became professor of physics in the college de France. He was made a member of the institute in 1803; and in 1804, it was solely through him that the institute voted against making Napoleon emperor. Along with Arago, he was made a member of the bureau of longitude, and (1806) sent to Spain to carry out the measuring of a degree of the meridian, preparatory to the introduction of the present French system of weights and measures. On his return, he devoted himSelf to physical researches and to lecturing. In 1815, the royal society of London elected him one of their 50 foreign members. In 1817, he visited England, and went as far n. as the Shetland islands, in order to make observations along the line of the English arc of meridian, which had been extended by col. Mudge. His most valuable contributions to science are on the polarization of light; and his researches connected with ancient astronomy are also very valuable. Of his numerous writings may be mentioned Irade Elementatre d' Astronomie
Physique, 3 vols. (Paris, 1805): 3d ed.. considerably augmented (1850), 6 vols., with vol. of plates—translated into English. Traitede.Physique, 4 vols. (1816); Precise de Physique, an abridgment of the former in 2 vols. (1817), often republished: Bernell d' Obserrations Giodisiques, etc. (1821). B. also contributed many excellent biographies of scientific men to the Biographie Universelle. Among the most important of his later works are Recherches stir l'aneienne Astronomie (Thinoise (1840); A !mare sur la Constitution de I' Atmosphere Terrestre, in the Connaissance des Temps (1841); and Etudes sur r Astronomie Indienne (1862). In 1849, B. was made a commander of the legion of honor, and he was also a member of most of the learned societies in Europe. IIe died Feb. 3, 1862.