ROEDERER, PIERRE LOUIS, COMTE French politician and economist, was born at Metz on Feb. 15, the son of a magistrate. He became councillor at the parle ment of Metz, and was commissioned in 1787 to draw up a list of remonstrances. His work advocating the suppression of internal customs houses (Suppression des douanes interieures, 1787) is a treatise on the laws of commerce and on the theory of customs imposts. In the Constituent assembly he was a member of the committee of taxes, prepared a new system of taxation, drew up a law on patents, occupied himself with the laws relating to stamps and assignats, and successfully opposed the introduction of an income tax. After the close of the Constituent assembly he was elected, on Nov. I1, 1791, procureur general syndic of the department of Paris. When he saw the perilous drift of things, he had tried to get into touch with the king; and it was on his advice that Louis, on the fatal loth, took refuge in the Assembly. Roederer was in hiding until after Robespierre's fall. Under the Empire, Roederer, whose public influence was considerable, was Joseph Bonaparte's minister of finance at Naples (1806), administrator of the grand duchy of Berg (i8I0), and imperial commissary in the south of France. During the Hundred Days he was created a peer of France. The Restoration government stripped him of his offices and dignities, but he recovered the title of peer of France in 1832. He died on Dec. 17, 1835.
His writings include: Louis XII. (1820) ; Francois I. (1825) ; Comedies historiques (1827-30) ; L'Esprit de la revolution de 1789 (1831) ; La Premiere et la deuxieme annee du consulat de Bonaparte (1802) ; Chronique des cinquante jours (1832) ; Memoire pour servir a l'histoire de la societe polie en France (1835).
See his Oeuvres, edited by his son (1853 seq.) ; Sainte-Beuve, Causeries du lundi, vol. viii.; M. Mignet, Notices historiques (1853). ROEMER, FRIEDRICH ADOLPH Ger man geologist, was born at Hildesheim, in Prussia, on April 14, 1809. In 1845 he became professor of mineralogy and geology at Clausthal, and in 1862 director of the School of Mines. He first described the Cretaceous and Jurassic strata of Germany in Die Versteinerungen des Norddeutschen Oolithen-gebirges (1836 39), Die Versteinerungen des Norddeutschen Kreidegebirges (1840-41) and Die V ersteinerungen des Harzgebirges (1843). He died at Clausthal on Nov. 25, 1869.
His brother, CARL FERDINAND VON ROEMER (1818-1891), edu cated for the legal profession at GOttingen, also became interested in geology, and abandoning law in 1840, studied science at the University of Berlin. Two years later he published his first work, Das Rheinische Vbergangsgebirge (1844), in which he dealt with the older rocks and fossils. In 1845 he visited America, the
results of his work being published in Texas and Die Kreidebildungen von Texas and ihre organischen Einschliisse (1852). From 1847 to 1855 Privatdozent at Bonn, he was then appointed professor of geology, palaeontology and mineralogy in the University of Breslau, a post which he held until his death on Dec. 14, 1891.
He prepared, with H. G. Bronn, the third edition of Lethaea geognostica, and later published one section, Lethaea palaeozoica, of an enlarged and revised edition. In 1862 he superintended the preparation of a geological map of upper Silesia, and the results of his researches were embodied in his Geologie von Oberschlesien. ROEMER, OLE (Latinized OLAus) (1644-1710), Danish astronomer, was born at Aarhuus, Jutland, on Sept. 25, 1644. He became in 1662 the pupil and amanuensis of Erasmus Bartholinus at Copenhagen. In 1671 he assisted J. Picard to determine the position of Tycho Brake's observatory (Uraniborg, on the island of Hveen). In 1672 he went to Paris with Picard, and spent nine years on observations at the new royal observatory and hydraulic works at Versailles and Marly. After a scientific mis sion to England (1679), on which he met Newton, Halley and Flamsteed, he returned to Copenhagen in 1681 as royal mathe matician and professor of astronomy in the university. He also held several public offices, including that of mayor (1705). He died at Copenhagen on Sept. 23, 1710.
Roemer is remembered as the discoverer of the finite velocity of light, which was suggested to him by his observations on the eclipses of Jupiter's moons. The first noteworthy transit instru ment was in 1690 erected at his house. He also set up at the university observatory an instrument with altitude and azimuth circles, and an equatorial telescope. He also built and equipped the "Tusculan" observatory at Vridlosemagle, near Copenhagen. His observations perished in the great fire of Oct. 21, 1728, except those discussed by J. G. Galle in 0. Roemeri triduum observa tionum astronomicarum a. 1706 institutarum (Berlin, 1845) See E. Philipsen, Nordisk Universities Tidskrift, v. 11 (1860) ; P. Horrebrow, Basis Astronomiae (Copenhagen, 1735) ; J. B. J. Delambre, Hist. de l'astr. moderne, ii. 632 ; J. F. Montucla, Hist. des mathemat iques, ii. 487, 579 ; R. Grant, Hist. of Phys. Astronomy, p. 461 ; R. Wolf, Gesch. der Astronomie, pp. ; J. F. Weidler, Historia Astronomiae, p. 538; W. Doberck, Nature, xvii. 105 ; C. Huygens, Oeuvres completes, t. viii. pp. 30-58 ; L. Ambronn, Handbuch der astr. Instrumentenkunde, ii. 552, 966 ; T. J. J. See, Pop. Astronomy, No. 105, May 1903.