[439] Pierre Simon Marquis de Laplace (1749-1827), a profound geometrician and a _protégé_ of d'Alembert, was Minister of the Interior for six weeks after the 18 Brumaire, entered the Senate in 1799, and became President of that body. He was a member of the French Academy, and was created a marquis and a peer by Louis XVIII. on becoming its President (1817).--T. [440] Joseph Louis Comte Lagrange (1736-1813), another famous mathematician. He was for twenty years President of the Berlin Academy (1766-1786). Napoleon made him a Grand Cross of the Legion of Honour, a count, and a senator. He and Laplace may be said to have completed Newton's work.--T. [441] Gaspard Monge, Comte de Péluse (1746-1818), a member of the Academy of Science, was for a month Minister of Marine under the Revolution (1792). During the wars of the Republic he devoted his knowledge to elaborating the national means of defense, was one of the founders of the Polytechnic School, accompanied Bonaparte to Egypt, and became President of the Cairo Institute. Napoleon gave him his title, created him a senator, and loaded him with honours, all of which he lost at the Restoration.--T. [442] Jean Antoine Chaptal, Comte de Chanteloup (1756-1832), a distinguished chemist and statesman. He was placed at the head of the gunpowder factory at Grenelle in 1793, and there displayed an incredible activity. In 1798 he became one of the original members of the Institute, Minister of the Interior in 1800, a senator in 1805, and a peer of France under the Restoration (1819).--T. [443] Claude Louis Comte Berthollet (1748-1822), another celebrated chemist, worked with Monge and Chaptal in the fabrication of gunpowder and the multiplication of the means of defense during the Republican wars. He also accompanied Bonaparte to Egypt, where he made many important researches. The Emperor made him a senator in 1805, and he received his peerage under the Restoration.--T. [444] Constantine I. Emperor of the West (274-337), known as Constantine the Great, was converted, by a sign of the Cross in the sky, in the year 312.--T. [445] Ps. XXIII. 7, 9.--T. BOOK II[446]