The New International Encyclopædia/Monge, Gaspard

MONGE, mō̇Nzh, Gaspard (1746-1818). A French mathematician, born at Beaune. He was educated at Beaune and at Lyons, and when only sixteen years old obtained a position to teach physics and mathematics at the latter place. From there he went, in 1765, to the school of engineering at Mézières as designer. He was soon made assistant, and in 1768 professor of mathematics in the military school itself. In 1780 he became a member of the Academy of Sciences at Paris, and in 1783 was appointed examiner of the naval pupils. From that time he lived in Paris. In 1792 he was appointed Minister of Marine, and the next year he took an active part in organizing the national defense. He was also active in the organization of public education, was one of the first professors in the Ecole Normale, and was one of the founders of the Ecole Polytechnique. He went with Bonaparte to Egypt in 1798, undertook the direction of the Egyptian Institute, and conducted the search for Egyptian antiquities. In 1805 he was appointed Senator, and in 1806 received the title of Comte de Péluse. After the Restoration he lost his offices, and at this time he fell into a state of melancholy from which he never recovered. He is famous chiefly as the founder of descriptive geometry (see Geometry), a science long kept as a Government secret. But he made important contributions to other branches of mathematics as well. The development of modern geometry dates from him; he introduced into analytic geometry of three dimensions a thorough treatment of linear equations, completed the study of surfaces of the second degree which had been begun by Euler, and established the principles of the integration of partial differential equations in connection with the theory of surfaces. Following are his principal publications: Traité élémentaire de statique (1788; 8th ed. 1846); Géométrie descriptive (1795; 7th ed. 1847; new German ed. 1900); Application de l'analyse à la géométrie des surfaces du premier et deuxième degré (1795; 5th ed. 1850). Consult: Dupin, Essai historique sur les travaux scientifiques de Monge (Paris, 1819); Brisson, Notice historique sur Monge (Paris, 1818); Obenrauch, Monge, der Begründer der darstellenden Geometrie als Wissenschaft (Berlin, 1893-94).