SLEEPING SICKNESS. 239 SLIDE RULE. as many years, and it is fatal. The victim ap- pears at first languid, weak, pallid, and stupid. His eyelids become pufl'y : an eruption appears on his skin. He falls asleep Mhilc talking, eat- ing, or working. As the disease progresses he is fed with difficulty and becomes mucli emaciated. The failure of nutrition and the appearance of bedsores are followed by convulsions and death. Some patients become insane. Jlanson has sug- gested FHaria perstaiis as the cause of the dis- ease. (See FiLABiA.) In 1S9S Cagigal and Lepierre of Coimbra, Africa, isolated a bacillus Ahich they believed was the cause ; but this claim is yet to be substantiated. Inoculations into rabbits of a culture of this bacillus caused similar symptoms to those exhibited by a young negro atl'ected with sleeping sickness, from whose blood they removed this bacillus for cultivation. Some cases of the disease have developed in Con- go negroes seven years after they iiave left Africa for a permanent residence in Europe. A few cases of the disease have been found among negroes in our Southern States. Consult Man- son, Tropical Diseases (London, 1900). SLEEP OF PLANTS. A popular name for the phenomenon of leaf movement in certain plants, especially of the Oxalideae and Legumi- nosie, whose leaves have a nocturnal position distinct from the diurnal. Usually the petioles rise or fall and sometimes the leaf blades be- come folded. The phenomenon is due to the sensitiveness of certain parts to variations in the intensity of the light reaching them, and has no likeness whatever to the sleep of animals. See Motor 0Rf4Axs : Movement. SLEEPY HOLLOW. A picturesque valley near Tarrytown, X. Y.. traversed by a small stream called the Pocantico River, famous as the scene of Washington Irving's Legend of i^leepii Hollow. It contains an old Dutch church, dating from 1699 and built of bricks brought from Holland. SLEEVE DOG. A Japanese breed of tiny spaniels. See Spaniel. SLEIDAN, sli'dan, or SLEIDA'NUS, Jo- HAXx (c.loOG-56). An early German historian whose real name was Philippson. He was born at Schleiden, near Cologne, studied law at Liege. Paris, and Orleans, and, entering the service of Francis I. of France in 15.37. acted as interme- diary between him and the Schmalkaldic League. In 1544 he made his home at Strassburg and thenceforth was active as diplomat, pamphleteer, and apologist in the cause of the Reformation. In 1551 he represented the city of Strassburg at the Council of Trent. His chief work is De Statu ReUfiionis et Reijiuhlicw Carolo Qiiinto Ccesare Commenturii (Strassburg, 1555: edited by Am Ende, Frankfort. 1785-8G), the best contempo- rary account of the Reformation, for the history of which it is still a valuable source. He also wrote Huinma Doctrinee Platonis de Jtepiiblica et de Leciibus (1548). Consult Baumgarten, Veber Sleidans Leben iind Briefwechsel (Strass- burg. 1876). SLEM'MER, Adam ,T. (1828-68). An Ameri- can soldier, born in Montgomery County. Pa. He graduated at West Point in 1850. "served against the Seminole Indians in Florida, and then for several years was stationed in various garrisons on the Pacific Coast. From 1855 to 1859 he taught at West Point. In January, 1861, he was in command of a small body of regular troops in Fort Barrancas, Pensacola Har- bor, Fla. Un the 10th of the month, after the surrender of the Pensacola navy yard, he trans- ferred his force to the more secure position afforded by Fort Pickens in the same harbor. This fort he successfully held against Confed- erate attack until he was reenforced. Promoted to be major, he was attached to General Buell's command and took part in the Corinth campaign and the advance on Nashville, became brigadier- general of volunteers (Xovember 29, 1862), and participated in the battle of Stone River (Decem- ber 31, 1862), receiving a wound that incapaci- tated him for further active service during the war. In 1865 he was brevetted colonel and brigadier-general in the regular service for meri- torious conduct and was commissioned lieuten- ant-colonel of the Fourth Infantry. He died while in command of Fort Laramie. SLENDER. An awkward, foolish country- man in Shakespeare's ilerrij Wives of Windsor, cousin to Shallow and a suitor of Anne Page. SLES'WICK. See Schleswig. SLICK, Sam. The pseudonym of the British- American humorist Thomas Chandler Halibur- ton (q.v.). SLICKENSIDES. The name given to the polished surfaces found along the joints and fault planes of rocks. They are caused by the rub- bing together of the rocks during faulting or dif- ferential movement along the planes of fracture. SLIDE (from AS. sUdan. to slide; connected with Ir.. Gael, slaod, slide, Lith. slysti, to slide, Skt. srirf/i, to go astray). A piece of mechanism applied to instruments of the trumpet and trom- bone family, for lengthening and shortening the sounding tube. (See Tkombone.) The term slide signifies a diatonic series of two or more tones, either ascending or descending, one of which is to be accented and the others played as grace-notes. SLIDELL', John (1793-1871). An American politician, liorn in New York City. He gradu- ated at Columbia College in 1810. In 1819 he removed to New Orleans and from 1829 to 1833 was United States District Attorney for Louisi- ana. In December, 1853, he became United States Senator, but resigned upon the secession of Louisiana from the "Union. In September, 1861, he was appointed commissioner of the Con- federate States to France, and ran the blockade from Charleston, S. C. At Havana, with James M. Mason, commissioner to England, he embarked upon the British mail steamer Trent, which was overhauled on November 8th by Captain Charles Wilkes in the United States sloop San Jacinto, and the envoys and their secretaries were ar- rested and confined for a time in Fort Warren, Boston. Upon the demand of England the act of Captain Wilkes was disavowed and the com- missioners sailed for England January 1, 1862. (See Trent Affair.) Mr. Slidell ' failed in securing the assent of France to the convention giving to that nation control of Southern cotton if the blockade should be broken, but was per- mitted to begin negotiations for the £15,000.000 Confederate loan. At the close of the war Slidell settled in England. SLIDE RULE. An instrument composed of sliding scales, and used to perform certain arithmetical calculations. The annexed figure
