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SIEMENS, SIR WILLIAM [KARL WILHELM] (...
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See also:SIEMENS, See also:SIR See also: See also:Joule's experiments had placed the See also:doctrine of the conservation of See also:energy on a sure basis. While See also:Rankine, See also:Clausius and See also:Lord See also:Kelvin were developing the dynamical theory of heat as a See also:matter of See also:physical and engineering theory, Siemens, in the See also:light of the new ideas, made a bold See also:attempt to improve the efficiency of the steam See also:engine as a converter of heat into mechanical work. Taking up the regenerator —a See also:device invented by See also:Robert See also:Stirling twenty years before, the importance of which had meanwhile been ignored—he applied it to the steam engine in the See also:form of a regenerative See also:condenser with some success in 1847, and in 1855 engines constructed on Siemens's See also:plan were worked at the See also:Paris See also:exhibition. Later he also attempted to apply the regenerator to See also:internal See also:combustion or See also:gas engines. In 1856 he introduced the regenerative See also:furnace, the See also:idea of his brother See also:Friedrich (1826-1904), with whom he associated himself in directing its applications. In an See also:ordinary furnace a very large part of the heat of combustion is lost by being carried off in the hot gases which pass up the See also:chimney. In the regenerative furnace the hot gases pass through a regenerator, or chamber stacked with loose bricks, which absorb the heat. When the bricks are well heated the hot gases are diverted so to pass through another similar chamber, while the See also:air necessary for combustion, before it enters the furnace, is made to See also:traverse the heated chamber, taking up as it goes the heat which has been stored in the bricks. After a suitable See also:interval the air currents are again reversed. The process is repeated periodically, with the result that the products of combustion See also:escape only after being cooled, the heat which they take from the furnace being in great part carried back in the heated air. But another invention was required before the regenerative furnace could be thoroughly successful. This was the use of gaseous See also:fuel, produced by the crude See also:distillation and incomplete combustion of See also:coal in a distinct furnace or gas-producer. From this the gaseous fuel passes by a flue to the regenerative furnace, and it, as well as the entering air, is heated by the regenerative method, four See also:brick-stacked See also:chambers being used instead of two. The See also:complete invention was applied at See also:Chance's See also:glass-works in Birmingham in 1861, and furnished the subject of See also:Faraday's farewell lecture to the Royal Institution. It was soon applied to many See also:industrial processes, but it found its greatest development a few years later at the hands of Siemens himself in the manufacture of steel. To produce steel directly from the ore, or by melting together wrought-iron scrap with See also:cast-iron upon the open See also:hearth, had been in his mind from the first, but it was not till 1867, after two years of experiment in " See also:sample steel works " erected by himself for the purpose, that he achieved success. The product is a mild steel of exceptionally trustworthy quality, the use of which for See also:boiler-plates has done much to make possible the high steam-pressures that are now See also:common, and has consequently contributed, Indirectly, to that improvement in the thermodynamic efficiency of heat engines which Siemens had so much at See also:heart. Just before his See also:death he was again at work upon the same subject, his plan being to use gaseous fuel from a Siemens producer in See also:place of solid fuel beneath the boiler, and to apply the regenerative principle to boiler furnaces. His faith in gaseous fuel led him to anticipate that it would in time supersede solid coal for domestic and industrial purposes, cheap gas being supplied either from See also:special works or See also:direct from the See also:pit; and among his last inventions was a See also:house See also:grate to See also:burn gas along with See also:coke, which he regarded as a possible cure for See also:city See also:smoke.
In electricity Siemens's name is closely associated with the growth of See also:land and submarine telegraphs, the invention and development of the See also:dynamo, and the application of electricity to See also:lighting and to locomotion. In 186o, with his brother Werner, he invented the earliest form of what is now known as the Siemens See also:armature; and in 1867 he communicated a See also:paper to the Royal Society " On the See also:Con-version of Dynamical into See also:Electrical Force without the aid of Permanent See also:Magnetism," in which he announced the invention by Werner Siemens of the dynamo-electric See also:machine, an invention which was also reached independently and almost simultaneously by Sir See also: While engaged in constructing a trans-See also:Atlantic See also:cable for the Direct See also:United States Telegraph See also:Company, Siemens designed the very See also:original and successful See also:ship " Faraday," by which that and other cables were laid. One of the last of his works was the See also:Portrush and Bushmills electric tram-way, in the See also:north of See also:Ireland, opened in 1883, where the See also:water-powerof the See also:river See also:Bush drives a Siemens dynamo, from which the. electric energy is conducted to another dynamo serving as a motor on the See also:car. In the Siemens electric furnace the intensely hot See also:atmosphere of the electric arc between See also:carbon pointsiis`'efnployed to melt refractory metals. Another of the uses to whith-he turned electricity was to employ light from arc lamps as a substitute for sunlight in hastening the growth and fructification of See also:plants. Among his miscellaneous inventions were the differential governor already alluded to, and a highly scientific modification of it, described to the Royal Society in 1866; a water-See also:meter which acts on-the principle of counting the number of turns made by a small reaction See also:turbine through which the See also:supply of water flows; an electric thermometer and See also:pyrometer, in which temperature is determined by its effect on the electrical conductivity of metals; an attraction meter for determining very slight See also:variations in the intensity of a gravity; and the bathometer, by which he applied this idea to the problem of finding the See also:depth of the See also:sea without a See also:sounding See also:line. In a paper read before the Royal Society in 1882, " On the Conservation of See also:Solar Energy," he suggested a bold but unsatisfactory theory of the See also:sun's heat, in which he sought to trace on a See also:cosmic See also:scale an See also:action similar to that of the regenerative furnace. His fame, however, doesnot See also:rest on his contributions to pure See also:science, valuable as some of these were. His strength See also:lay in his grasp of scientific principles, in his skill to perceive where and how they could be applied to practical affairs, in his zealous and instant pursuit of thought with action, and in the indomitable persistence with which he clung to any basis of effort that seemed to him theoretically See also:sound. Siemens's writings consist for the most part of lectures and papers scattered through the scientific See also:journals and the publications of the Royal Society, the Institution of See also:Civil Engineers, the Institution of Mechanical Engineers, the Iron and Steel Institute, the British Association, &c. A See also:biography by Dr William See also:Pole was published in 1888. (J. A. Additional information and CommentsThere are no comments yet for this article.
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