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STEAM-SHOVEL AND DREDGE Deutschland is 570 tons. In the United States, steamship-building has until recent years been largely confined to vessels for inland waters. The river steamboats of the United States are fine examples of boat-building. They must ascend rivers against strong currents, and often need to travel in shallow waters and carry large amounts of freight or tow large fleets of barges. This has developed a large vessel of only a few feet draught and with very powerful engines. On the western rivers most of the boats have stern-wheels. The steamers on the Great Lakes rival ocean-steamers in speed, size and equipment. Most of them are engaged in the transportation of grain and of iron-ore. Since 1883 ocean-steamship building in the United States has developed largely, owing to the impetus given by the construction of the large government cruisers and warships of “the new navy.” The largest and finest commercial steamships built in the United States are the Minnesota and her sister-ship, built at New London, Conn., for the Pacific trade, the former being 630 feet long and having, when built, the greatest depth of any ship on the ocean. See, , and.  Steam-Shovel and Dredge, a machine, worked with crane and steam-power attached, mounted on wheels for running on rails, and used for excavating clay, sand, gravel or other soil in railroad or other cuttings; also used for river-dredging, the deepening of canals etc. by a suction-process. The steam-shovel in use for heavy work has a boom, usually made of strong steel-girders, with a powerful thrusting-engine for giving ample scooping-force to the shovel, the latter generally being provided with heavy, pointed teeth for excavating loose rock. The bottom of the shovel or bucket is hinged, so that, when filled and raised, its contents are released by pulling a latch-cord and dumping the load into cart, car or other vehicle for removal. The thrusting of the shovel, as well as the hoisting and dumping, is the work of the attached engine, working along the movable crane. With a 2½ or 3 cubic-yards' shovel about 2,400 cubic yards of sand and 600 of loose rock can be excavated in ten hours. For dredging river-bottoms and delivering the mud or other material on shore, machines with belt-conveyors are used, different in pattern and varying in capacity and rapidity in work. Some varieties deliver to the shore or to a scow alongside by gravity, by means of an extensible sheet-iron trough or sipper-shovel of large dimensions.  Steam-Turbine. See.  Steam-Whis′tle, a mechanism attached to the steam-boiler in a railway-locomotive, marine engine etc., through which the escaping steam, issuing from a narrow annular orifice in a hemispherical cup, strikes the thin edge of a bell on top and produces a loud, more or less prolonged whistle, which serves as signal or warning.  Sted′man, Edmund Clarence, an American poet was born at Hartford, Conn., Oct. 8, 1833. He studied at Yale, and began his literary career as a journalist, acting as correspondent for The New York World during the Civil War. He also contributed to magazines. His first volume of poetry, published in 1860, was rapidly succeeded by others. Victorian Poets, which has gone through several editions, appeared in 1875, and Poets of America in 1885. With Ellen M. Hutchinson he edited The Library of American Literature, and he also brought out a Household Edition of his poems. Other works edited by him include A Victorian Anthology, An American Anthology, Poe's Works, Landor's Poems and Aldrich's Poems. He died on Jan. 18, 1908.  Steel is iron carbonized. It is of several sorts, each possessing special properties and being made by a particular process; is extremely elastic; and has greater tensile strength than any other metal. No law of connection between its composition and its properties has been discovered, and carbon's form in steel remains undetermined. The term formerly designated a carbonized iron that would harden when heated to a certain, temperature and then suddenly cooled; but only carbonized iron produced by modern methods is now considered steel. Iron is used in the industrial arts as cast-iron, wrought iron and steel, and each has marked physical properties that fit each for special purposes.

Cast iron is produced by heating iron-ores to a high temperature in a blast-furnace in connection with various fluxes, particularly limestone. The molten metal contains considerable carbon dissolved and, usually, silicon, phosphorus and sulphur. The amount of carbon in cast iron varies from 1.5% to 4.5%. Cast iron can be melted and cast in molds. It is only slightly malleable, except when specially treated, is rigid and has great resistance to crushing, but is more or less brittle and not adapted to tensile strains. Wrought iron is nearly pure iron, and in modern metallurgical processes is usually obtained by removing the carbon and other impurities from cast iron. The common method of making wrought iron is that of puddling. This consists of melting cast iron in the chamber of a flame-furnace (see ) and in removing the carbon, phosphorus etc. by stirring the molten metal and, sometimes, by adding oxidizing materials. Wrought iron is very malleable, can be welded, has a high tensile strength and shows a fibrous rather than a crystalline structure at a break. Steel has been made since very early times by a