262 REGIS REGNAULT called him to Rome to reform the calendar, and not long before his death appointed him bishop of Ratisbon. According to some au- thorities, he was assassinated by the sons of George of Trebizond, in whose translations Regiomontanus had detected grave errors ; according to other accounts, he died of the plague. He was the first in Europe to publish an astronomical almanac, improved the knowl- edge of algebra, introduced decimal fractions, greatly promoted the science of trigonometry, and was the most eminent astronomer that Europe had produced. His works include Calendafium (in Latin and German, Nurem- berg, about 1473); Ephemerides from 1475 to 1506, continued by Bernhard Walther and published in 1544 by Schonerus; De Refor- matione Calendarii (Venice, 1489); De Come- tce Magnitudine, Longitudineque (Nuremberg, 1531); De Triangulis (1533) ; and Tabulae Di- rectionum Profectiortumque in Nativifatibut multum utiles (Veaice, 1585). See Regiomon- tanus als geistiger Vorldufer des Columbus, by Alex. Ziegler (Langensalza, 1874). REGIS, Jean Baptist* de, a French geographer, born at Istres in Provence about 1665, died in China about 1737. He was a Jesuit, and was sent to China as a missionary about 1700. His scientific attainments gained him a place at court and the favor of the emperor Hang-he, who in 1707 placed him at the head of a com- mission of Jesuits for making a survey and drawing up a map of the Chinese empire. Be- ginning with the great wall and the adjacent provinces, ho completed a 15 ft. map of them, which he presented to Hang-he in January, 1709. He then drew up maps of Mantchooria, Pecheli, and the region drained by the Black river (1710); in 1711-'13 he surveyed and mapped Shantung, Honan, Nanking, Chekiang, and Fokien. The health of his companions failing, he accomplished alone the survey of Yunnan, and, assisted by Father Fridelli, he finished the maps of Kweichow and How- kwang (nowjjlupeh and Hunan). While thus completing surveys of extraordinary magni- tude, he also wrote a full history of his labors, which is in part condensed in the preface to Du Halde's Description de la Chine (4 vols. fol., Paris, 1735). Of the copious memoirs which he composed on the topography of the various provinces, their resources, and the manners and customs of the inhabitants, only two frag- ments are published by Duhalde in vol. iv. of his Description, one relating to Corea and the Coreans, and the other on Thibet and the hi- erarchy of the lamas. His knowledge of Chi- nese enabled him to translate into Latin the Yih-king, with copious notes and dissertation* (edited by Julius Mohl, 2 vols., Stuttgart and Tubingen, 1834), the manuscript of which is in the national library of Paris. His labors were interrupted in 1724, when the emperor Yung-ching proscribed the Christian religion. REGXARD, Jean Francois, a French dramatist, born in Paris in February, 1655, died Sept. 4, 1709. He inherited great wealth arid led a roving life. In Bologna he fell in love with a lady whom he made the heroine of his novel, La Protencale. She and her husband, whom he designates as M. de Prade, left Genoa on the same boat with him in 1678, and they were all captured by Algerine pirates. He and the lady were ransomed, and together went to Paris in the belief that the husband was dead ; but on finding him alive after reaching that capital, Regnard in despair re- sumed his wandering life. After exploring Lapland, and travelling through Poland, Tur- key, Hungary, and other countries, he returned to France about 1683; and for most of the remainder of his life he was prominently connected with the ministry of finance, and his house in the rue Richelieu was a resort of wits. He was one of the best followers of Moliere, and excelled as a satirical poet. His Le joueur (1696) is one of the masterpieces of the French stage. The French academy in 1857 awarded a prize for the best eulogy of him. The best of the numerous editions of his works are by Crapelet (6 vols., Paris, 1822) and by Alfred Michiels, with an essay and bio- graphical notices (2 vols., 1854). REGYULT, Ellas Georges Sonlange OUya, a French historian, born in London, April 22, 1801, died in Paris, Jan. 4, 1868. The son of a French physician, he studied law in Paris, and became an advocate. In 1848 he was a prominent official in the ministry of the inte- rior, and subsequently in that of finance. He published histories of Ireland and England ; ffistoire de Napoleon (4 vols. 18mo, 1846-'7) ; ffistoire de huit ans (3 vols., 1851-'4), as a continuation of the ffistoire de dix ans by Louis Blanc, who however disputed its char- acter as such ; a history of the Danubian prin- cipalities, &c. He also translated works of Bentham and Wordsworth, and in conjunction with others Carlyle's " History of the French Revolution " (3 vols., 1866-7). REGMILT, Henri Victor, a French physicist, born in Aix-la-Chapelle, July 21, 1810. He studied at the polytechnic school of Paris from 1830 to 1832, and was professor at Lyons till 1840, when his Memoire sur faction du More sur fether chlorhydrique secured his admis- sion to the academy of sciences and his ap- pointment to the chair of physical sciences in the polytechnic school, and in 1841 in the college de France. He was chief engineer of mines from 1847 to 1854, when he became director of the porcelain works at Sevres. In 1848 he received the Rumford medal from the royal society of London for his " Experiments to determine the Laws and the Numerical Data which enter into the Calculation of Steam Engines," and subsequently became one of the 50 foreign members of that body, which pre- sented him with the Copley medal in Novem- ber, 1869. His attention has been devoted chiefly to heat, and he was the first to demon- strate that the latent heat of steam diminishes