BOSCOVICH, ROGER JOSEPH (I 71 one of the foremost Serbo-Croat scientific writers, and among the earliest of foreign savants to adopt Newton's gravitation theory, was born at Ragusa in Dalmatia on May 18, 17II, according to the usual account, but ten years earlier according to Lalande (Eloge, 1792). In his 15th year he entered the Society of Jesus. He studied mathematics and physics at the Collegium Romanum ; and in 1 740 was appointed professor of mathematics in the college. He published dissertations on the transit of Mercury, the Aurora Borealis, the figure of the earth, the observation of the fixed stars, the inequalities in terrestrial gravitation, the application of math ematics to the theory of the telescope, the limits of certainty in astronomical observations, the solid of greatest attraction, the cycloid, the logistic curve, the theory of comets, the tides, the law of continuity, the double refraction micrometer, various problems of spherical trigonometry, etc. In conjunction with Christopher Maire, an English Jesuit, he measured an arc of two degrees be tween Rome and Rimini, and in 1755 published De Litteraria ex peditione per pontificam ditionem ad dimetiendos duos meridian grades a PP. Maire et Boscovich. The value of this work was increased by a carefully prepared map of the States of the Church. A French translation appeared in 1770. In 1771 he published at Vienna his famous work, Theoria plzilosophiae naturalis redacta ad unicam legem virium in natura existentiurn, containing his atomic theory (see MOLECULE). During a visit to England on one of the numerous diplomatic missions with which he was entrusted, Bosco vich was elected a fellow of the Royal Society.
In 1764 Boscovich was called to the chair of mathematics at the University of Pavia, and this post he held, together with the direc torship of the observatory of Brera, for six years. On the sup pression of his order in Italy (1773) he accepted an invitation from the king of France to Paris, where he was naturalized and appointed director of optics for the marine, an office instituted for him, with a pension of 8,000 livres. He remained there ten years, but his position became irksome and at length intolerable. In 1783 he returned to Italy, and spent two years at Bassano, where his Opera pertinentia ad opticarn et astronomiam, etc., appeared in 1785 in five volumes quarto.