STURGEON. 643 STURM. but the average is much less. Its sides are red- dish, often with irregular blackish spots. Very- peculiar in its prolonged paddle-shaped snout is the 'shovelnose' or 'white' sturgeon («S'c(i;</ii- rhynclius plati/rhynchiis) . which is pale olive in color and about five feet long. It is a denizen of the Western and Southern States. Similar spe- cies occur in Asia. The largest of American sturgeons is that of the Pacific Coast (Acipenser t7-ansmontanus) called 'white" in comparison with the rare 'green' sturgeon (.lei/ioiicr incdi- roxtris). The former weighs 300 to 000 pounds, and is used as food, but the latter, which is near- ly as large, but olive green, is not eaten. A giant beside these is the great Russian 'bielaga' or 'huso' (Acipenser huso), which has been known to attain a length of '20 to 25 feet and a weight of 3000 pounds. It is this species, once extremely abundant in the Danube. Volga, and other large rivers emptying into the Black and Caspian seas, which has furnished mainly the salted roe called caviar (q.v.), though some comes from the diminutive sterlet [Acipenser ruthe- niis) of the same region. The air bladder is also utilized for making isinglass. Fossil stvirgeon remains indistinguishable from the corresponding portions of the skeletons of modern species have been found in rocks as old as the Eocene. Earlier less specialized ancestral forms are Chondro.steus of the .Jurassic and per- haps also the still older Paheoniscus of the Permian and Cheirolepis of the Upper Devonian. See C'HiEOLEPis : Chondrosteis ; P.^l.eoniscus. Consult authorities cited under FisH and Fisheries; and see Plate of Sturgeons. STURGEON, stur'jiin, William (17831850). An English electrician, born at Whittington, in Lancashire. As early as 1823 he constructed a soft-iron electro-magnet, and in 1830 described for the first time the process of amalgamating the zinc plate of a battery with mercury. In 1832 he constructed an electro-magnetic ro- tary engine, the first contrivance by means of which any considerable mechanical force was developed by the electric current ; and he shares the honor of this invention with Oersted. Five years afterwards he produced an electromagnetic coil for giving shocks. About the same time he ascertained by means of kites that in fair weather the atmosphere is positive with regard to the earth. Later he devised and constructed the commutator, now in universal use. Among his works are : Experimental Re- searches in Electro-Magnetism. Galranism, etc. (1830) ; Lectures on Electricity Delivered in the Royal Victoria Gallery, Manchester (1842); Ticelre Lectures on Galranism (1843) ; and Scl- ent i fie I'rscinches (1850). STURGEON BAY. The county-seat of Door County. Wis., 45 miles northeast of the city of Green Bay. on a canal coimecting CJreen Bay and Lake Michigan, and on the Ahnapee and Western Railroad (Jlap: Wisconsin. F 4). It has con- siderable industrial importance. There are can- ning estabHsbments, ship yards, and manufac- tories of lumber, beer, flour, foundry and ma- chine-shop products, etc. Population, in 1890, 2195: in 1900, 3372. STUR'GIS, Russell (1836—). An Ameri- can architect and author, born in Baltimore. Md. He studied architecture in New York and in Kurope, and practiced his profession from 1865 till 1880. In that time he designed Battell Chapel, Farnam Hall, Durfee Hall, and Lawrence Hall of Vale College; the Homa'opathic Medical College and Flower Hospital in New York, and many other buildings in various parts of the country. In 1878 he became profes.sor of archi- tecture and the arts of design in the College of the City of New York, but resigned in 1880 on account of ill health, and went abroad for five years. After 1885 he was editor of decorative art and mediaeval arch;eology of the Ccnturx/ Dictionary ; editor of fine arts of ^yehster's In- ternational Dictionary ; and editor of archseology and fine arts of Johnson's (now Appleton's) Universal Cyclopaedia (ed. of 1893-95). In January, 1898, he began editing the "Field of Art," a department in Scrihncr's Magazine. His published works include: Manual of the Jarves Collection of Early Italian Pictures (1868); European Architecture : An Historical Stud;/ (1895); Annotated Bihliograplty of Fine Art (1897) ; and How to Judge' Architecture (1903). He contributed articles on art subjects to the yew International Encyelopcedia, and he was the editor and chief author of the Dictionary of Architecture and Building (1901-02). STURGIS. S.MLTEL Davis (1822-89). An American soldier, born at Shippensburg, Pa. He graduated at West Point in 1846, served through the Mexican War, and was taken prisoner during the operations before Buena Vista. At the out- break of the Civil War he was obliged to abandon Fort Smith, Ark., of which he was commandant, but succeeded in saving his command. As major of the Fourth Cavalry he served in 1801 under (ieneral Lyon, and succeeded to his command at Wilson's Creek (q.v. ) . He was prominent at South Mountain, Antietam, Fredericksburg, and had command of the cavalry of the Department of the Ohio in 1863-64, in Januai-y of the latter year capturing tieneral Vance and his command and routing General Martin's Confederate cav- alry. Later he took an important part in an expedition against General Forrest. In 1S69 he was promoted to be colonel of the Seventh Cav- alry. From 1881 to 1885 he was governor of the Soldier's Home near Washington, and the next year he retired from active service. STURLUSON, Snorri. See Snorhi Sturlu- SON. STURM, sturm. .Jacques Charles Fran- <;ois (1803-55). A French mathematician, bom. at Geneva. He was educated at the Acad- emy of Geneva, and in 1827, with his friend Colladou, took the Grand prix de mathi- matiques for the best memoir on the compression of liquids. The famous theorem that bears his name was discovered in 1829. A statement of the results secured by this theorem requires the definition of Sturm's fimctions: If f (x) =: be freed from equal roots, and f {x) be divided by f'(x) (the derivative of fix)), and the last divisor by the last remainder, changing the sign of each remainder before di- viding by it. until a remainder independent of X is obtained, or else a remainder which cannot change its sign, then f[x), fix), and the suc- cessive remainders, constitute Sturm's functions. The theorem asserts that if. as x increases, Hx) passes through the value zero, Sturm's functions lose one change of sign : if any other of Sturm's functions vanishes, there is neither
