SPRENGEL. 470 SPRING. 1803; 4th ed. 1846), Bandbuch der Pathologie (1705-97: 4th ed. 1815), Hisloria Rci Herburke (1807-08), Oeschichteder Botanik ( 1817-18), and jW»e EnUlcckungen im ganzen Umfange der Pflaiizenkuinlc (181U-22). SPRENGER, spi-eiiB'tT, ALOY.S (1813-03). A German-English Orientalist, born at Nassereit, Tyrol. He was educated at Innsbruck and at the Universit}' of Vienna. In 1836 he settled in London and became a naturalized British subject. In 1843 he proceeded to Calcutta under an ap- pointment to the medical service of the East In- dia Company. In 1844-48 lie was principal of the Jlohamniedan College at Delhi. In Decem- ber, 1847, he became an assistant resident at Lucknow. where he was employed for some time in cataloguing the manuscripts in the roval library of the King of Oudh. From 1851 to 1854 lie was oificial Persian translator at Calcutta, and principal of the ilohamnicdan College at Hoogli. During these years he traveled extensively through the Orient, gathering materials for his projected Life of Mohammed, the first portion of which was published at Allahabad in 1851. In 1857 he re- turned to Europe, and settled at Heidelberg. In 1858-81 he was professor of Oriental languages at the University of Bern. The remainder of liis life he spent in retirement at Heidelberg. His published works include: Technical Terms of the iSuffecs (1844); An Eiiglish-Uindustuni (Irnin- mnr (1845); Selections from Arabic Authors (1845); The History of Mahmiid Ghaznih (1847) ; The GuUstan of Saadi (1851), a trans- lation from the Persian; Lebcn vnd Lehre des Mohammed (3 vols., 1861-63); and Die alte Geogra ph ie A ra b tens (1875). SPRING (AS. spring, sprgng, OHG. spring, spni II ;i, Ger. Spring, spring, from AS. springan, sprincan, OHG. springan, Ger. springen, to spring, leap; probably connected with CJk. <r-ipx(<r8ai, spcrchesthai, Lith. spriigti, to spring away, es- cape). A subterranean stream which discharges at the earth's surface. Host springs are fed by meteoric waters in the form of rain and snow that percolate into the soil and accumulate at some depth in the strata. This accumulation is known as ground water, and its upper surface, which is called the water-level, coincides more iBBANGEMENT OP BTHATA 0AC8ISQ A BPBING. The water collects in the depression A. and percolating throug:h the porous stratum D, issues at B as a spring. C and E are impervious layers which prevent the escape of the water above or below D. or less closely with the surface of the ground, receding from it, however, under the hill crests and approaching it closely under the valleys. Yhen the side of a valley is steep or its floor is much deitressed the ground water may come to the surface and escape as a spring. Springs may also be formed by the percolating waters encountering an impervious layer of clay or cemented sand which retards their further de- scent, causing them to follow this dense stratum until they emerge on some hill slope. Springs of this character are more or less dependent on rainfall. All water in penetrating the soil and rocks, even if at no great depth, becomes more or less charged with dissolved mineral and or- ganic matter, as by reason of its carbonic acid it possesses marked solvent powers. Spring waters therefore commonly contain various solid substances in solution, such as the carlionate, sulphate, or muriate of lime, salts of soda, pot- ash, magnesia, and iron, or more rarely silica. When the quantity of dissolved solids is un- usually large the spring is termed a mineral spring, and is often utilized for medicinal pur- poses. See Mineral ^YATERS. Underground waters may collect above an im- pervious stratum which does not appear at the surface, and they escape by slow percolation through the overlying strata, forming a marsh or swale. To such marshy tracts occurring in the arid regions of California, Arizona, and Mexico, the name cienega has been given. Thermal springs, whose temperatures are nota- bly higher than that of ordinary springs, usually have a deep-seated origin. In regions where the rocks have been greatly disturbed and fractured the surface waters penetrate to great depths, and thus become warmed by the interior heat of the earth, or they may be heated from contact with uncooled masses of lava. It is also known that igneous rocks of all kinds give off a great quan- tity of vapor during the process of cooling, and some springs thus may be fed by waters whose source lies deep within the earth, and which for the first time appear at the surface. Ther- mal springs are mostly limited to mountainous regions; in the United States they occur in great numbers along the Appalachians and the Rocky ilountains. In company with geysers they are found in the Yellowstone Kational Park, Iceland, and New Zealand. Consult Schlichter, The Motion of Underground Water. Water Snp- ph) and Irrigation Papers, No. 67, United States Geological Survey (Washington, 1002). See Artesian Wells; Gey.sers; C4eology. SPRING. A term used in mechanics to desig- nate variously constructed devices of metal or other elastic material adapted to resist concus- sion, to supply motive power, or to register stress through their property of tending to re- turn to their original form. A spiral spring is one which is wound around a fixed point or cen- tre in constantly receding coils, like the main- spring of a watch or clock. Spiral springs are usually made of flat strips or ribbons of steel, but may be made of round or other shaped wire. A helical spring is one which is wound around a cylindrical arbor in advancing spirals like the thread of a screw. Helical springs are usually made from round bars or from square rods of steel, and are perhaps more extensively used than any other form. An elliptical or laminated spring is made of flat bars, plates, or 'leaves' of regularly varying lengtlis superposed one upon the other. For formulas for calculating the strength and energy of springs of various formiS and sizes, consult Kent, Mechanical Engineers' Pocket Book (New York, 1000). SPRING, Gardiner (1785-1873). An Ameri- can Presbyterian clergyman, son of Samuel Spring (q.v.). He was born at Newburyport, Mass., and was graduated at Yale College in
