SIDDONS. 139 SIDNEY. which made her irresistible. As a tragic actress she has probably never been equaled in Great Britain. Her picture as the "Tragic Muse" by Sir Joshua Reynolds is famous. Consult: ISoaden, Memoirs of Mrs. Siddons (London, 1S27; 2d ed. 1831) ; X'ampbell, Life of Mrs. tiiddons (ib., 1834) ; Fitzgerald, Tlic Kern- blcs (ib., 1871); Kcnnard, Mrs: tiiddons (ib., 1887) ; Baker, Our Old Actors (ib., 1881) ; Mat- thews and Hutton, Actors and Actresses of (Ireat Britain and the Vnit'ed .S7o?cs(New York, 1886) ; Doran, Annals of the Stage (ed. Lowe, London, 1888). SIDEREAL CLOCK (from Lat. sidcrcns. re- lating to a star, fnini sidus, constellation, star). A clock regulated to indicate sidereal time. (See Day.) The sidereal clock is a most important aid to the practical astronomer, and is one of the indispensable instruments of an observatory. See Clock. SIDERITE (Lat. sideritis, loadstone, from Gk. (TiS-qpiT-qs, sidcritcs, relating to iron, from fftSripos, sideros, iron). A mineral iron carbonate crystallized in the hexagonal system. It has a vitreous lustre, and is of a gray, brown to red, and sometimes green color. It occurs in gneiss, mica, and clay slates, and in other rock strata, and also frequently with metallic ores. It is found in Freiberg, Austria, in the Harz, and in Greenland : in the United States it occurs in various places in Vermont, Massachusetts, New York, and Ohio, and other localities where iron ores are common. Its iron is often partly re- placed by calcium, magnesium, and manganese. It also occurs in crystallized, coneretionar}', massive, and earthy forms. The name siderite is also applied to a trans- lucent blue variety of vitreous quartz, which is also more commonly called sapphirine. SID'EKOX'YLON ( Neo-Lat., from Gk. ffiSn- pos, sidfros, iron -f- ^liXov, xylon. wood). A genus of trees of the natural order Sapotaceie, with evergreen leaves and axillary clusters of flowers, natives of and widely distributed in warm climates. They are remarkable for the hardness of their wood, which is sometimes called ironwood. and ij, at least in some species, so heavy as to sink in water. A single species, Sideroxi/Ion Masticliodendron, occurs along the east coast of Florida, where it is known as mastic and wild olive. SIDEWALK, Traveling. See Traveling Sidewalk. SIDEWINDER. The local name in Arizona for the horned rattlesnake (Crotalns cerastes), which inhabits open plains, and when disturbed moves away sideways. Consult ]Ierriam. The Death Valley Expedition (Agricultural Depart- ment, Washington. 1803). See Rattle.s.vake and Plate of Rattle,snake.s. SIDGKWICK, Hexrt (1838-1901). An Eng- lish moralist and economist, born at Skipton. Yorkshire, in 1838. He w'as educated at Rugby and Trinity College, Cambridge, was fellow of Trinity College from 1859 to 1869. and lecturer from 1859 to 1875. when he was appointed pr.-e- lector of moral and political philosophy; and in 1883 he Avas appointed Knightbridge professor of moral philosophv. His principal woi-ks are: The Methods of Ethics (1874; 5th ed. 1893); The Principles of Political Economy (1883); Vol. XVIII.— 10. Outlines of the History of Ethics (1886; 4th ed. 1896) ; and The Elements, of PolMes (1891). He took a pruuiiuent part in the promotion of the higher education of women at Cambridge, and was one of the founders of Newnluim College. He was a public-spirited man, and was liberal with his money. He helped largely to support Mind, the English pliilosophical quarterly, of which he was co-editor. He resigned his chair, ]lay 1, 1900, on account of ill hcaltli. His Methods of Ethics is a very noteworthy work, in which lie criticises in a remarkably fair spirit the ethics of intni- tionism (q.v. ) and common sense, of egoistic hedonism (q.v.), and of utilitarianism (q.v.), finally giving hisadlierencetoa utilitarianism with an intuitive basis in the abstract moral principles of justice, prudence, and rational benevolence. He was a notable member of the Society for Psychical Research, in regard to the work of which lie maintained a cautious and conservative position. See Stephen, "Henry Sidgwick," in Mind (.January, 1901) ; .James Seth. "The Ethical System of Henry Sidgwick," in Mind (April, 1901) ; Sorley,"Henr.v Sidgwick." in International Journal of Ethics (January, 1901); Haywood, "The True Significance of Sidgwick's Ethics," ib. SIDI-BEL-ABBES, se'de bel ab'bas'. The capital of an arrondissement in the Department of Oran, Algeria, on the Mekerra, 48 miles by rail south of Oran (Map: Africa, D 1). It is comparatively a modern town and is surrounded by walls. It has a considerable agricultural trade in grain, alfalfa, and cattle. Population, in 1901 (of commune), 25,739. SIDI MOHAM'MED (1803-73). Emperor of Morocco from 1859 to 1873. He succeeded his father, Muley Abderrahman. He was soon in- volved in a war with Spain, caused by the ma- rauding expeditions of the Rifl pirates, was de- feated by the Spanish under Prim and O'Donnell (1860). and obliged to pay an indemnity of 200,000,000 piasters. His introduction of re- forms and the commercial concessions which he granted to foreigners caused^ several insurrec- tions, in quelling one of which he lost his life. See Morocco. SIDMOUTH, sid'muth. A watering place on the southern coast of Devonshire. England, at the mouth of the little river Sid. remarkable for its healthful climate and picturesque situation (Map: England, C 6). The esplanade, protected by a sea wall 1700 feet in length, forms an excel- lent promenade. The interesting parish cliurcli dates from 1259. Sidmouth was the residence of Queen Victoria when a child, and her father, the Duke of Kent, died here in 1820. Population, in 1991. 4200. SIDMOUTH, Henry Addington, first Vis- count (1757-1844). An English statesman. See Addington, Henry. SID'NEY. The county seat of Shelby County, Ohio, 40 miles north of Dayton ; on the Miami River, and on the Cincinnati, Hamilton and Day- ton, and the Cleveland, Cincinnati, Chicago and Saint Louis railroads (Map: Ohio, P. 5). ffhe public library, jNIonumcntal Building, court- house, and Wagner's Park are noteworthy fea- tures. Sidney has considerable industrial impor- tance. The manufactures include road scrapers, whips, hollow ware, corn shellers, horse collars, fly nets, poles and shafts, churns, wheels, car-
