Page:The American Cyclopædia (1879) Volume III.djvu/574

 568 CALCASIEU CALCULATING MACHINES formations, which contain little or no limestone, this being in these instances supplied to the wa- ter from some distant formations through which it has flowed. Thus the carbonate of lime re- quired by shell fish and plants is distributed abundantly in places that would otherwise he destitute of it. Sir Charles Lyell states that in central France, a district where the pri- mary rocks are unusually destitute of lime- stone, springs copiously charged with carbon- ate of lime rise up through the granite and gneiss. Some of these are thermal, and proba- bly derive their origin from the deep source of volcanic heat once so active in that region. One of these springs near Clermont has formed by its incrustations an elevated mound of tra- vertine, or white concretionary limestone, 240 ft. in length, and at its termination 16 ft. high and 12 ft. wide. Another in the same region rises in a gneiss country at the foot of a vol- canic cono, at least 20 m. from any calcareous rock. The deposit of these springs is often a spongy, porous substance called calcareous tufa, or calc tuff. It takes the impression of the objects it encloses, as leaves, twigs, and branches of trees, and retains the forms, if not the material itself, in its solid substance. When freshly quarried, it is easily cut into any shape, and is therefore conveniently applied to build- ing purposes. The temples of Psestum are built of it, and the stone has in them assumed great strength and solidity. In the central parts of New York, especially in the vicinity of Seneca and Cayuga lakes, deposits of this nature are very frequent. They form beds of marl be- neath muck swamps, and in the bottoms of ponds and lakes. Wherever the calcareous water flows, the aquatic plant chara grows abundantly, so as sometimes to obstruct the watercourses, and render its removal necessary. As the plant grows, its stems become incrust- ed with carbonate of lime, and new green growth continues to shoot out beyond, which is soon to be filled in with the same stony in- crustation. The abundance of calcareous mat- ter is as favorable to the growth of fresh- water testacea as of the chara; and those which are found in the oldest of these forma- tions are still of the common living fresh-water species. CALCASIEU, a river of Louisiana, not navigable. It rises in Sabine parish, in the western part of the state, flows through Rapides and Calca- sieu parishes, and after a southerly course of about 200 m. enters the gulf of Mexico. An expansion of the river near its mouth, about 18 m. long and 5 m. wide, is called Calcasieu lake. CALCASIEU, a 8. W. parish of Louisiana, bor- dering on Texas and the gulf of Mexico, hav- ing the Sabine river on the W., and the Mermenteau and Bayou Nepique on the E. ; area about 5,000 sq. m. ; pop. in 1870, 6,733, of whom 1,457 were colored. It is intersected by Calcasieu river and watered by several of its branches. The soil in the vicinity of the streams is fertile, and the surface, which is level, is principally occupied by savannas, or grassy plains, affording pasturage to large num- bers of cattle. The chief productions in 1870 were 39,950 bushels of Indian corn, 15,512 of sweet potatoes, 28 hhds. of sugar, 1,120 gallons of molasses, and 605 bales of cotton. There were 886 horses, 1,347 milch cows, 3,666 other cat- tle, 1,900 sheep, and 4,227 swine. Capital, Lake Charles Court House. CALCHAS, a legendary Greek soothsayer, horn at Megara, induced by Agamemnon to accom- pany the expedition to Troy. He ordered the sacrifice of Iphigenia, foretold the length of the Trojan war, explained the cause of the pesti- lence that ravaged the Grecian army, and ad- vised the stratagem of the wooden horse. On his return to Greece he died, in accordance with the prediction of an oracle, on meeting Mopsns, whose power of divination exceeded his own. CALCIUM (Lat. calx, lime), the metallic basis of lime. It is one of the most abundant and important constituents of the crust of the globe, occurring as limestone, gypsum, fluor spar, and phosphates, and in the animal kingdom making up the solid part of the bone. The metal is not found in nature in its pure state, but always in combination. Sir Humphry Davy first prepared the metal in 1808, hut not in sufficient quantity to thoroughly investigate its properties. Several methods have been pro- posed for the isolation of calcium, among which the following are most worthy of men- tion. Matthiessen employed the electrolytic decomposition of a mixture consisting of two equivalents of chloride of calcium and one equivalent of chloride of strontium. Lies-Bodart obtained it still more easily by fusing iodide of calcium with an equivalent quantity of sodium; and Caron performed the reduction of the chloride by means of zinc. Calcium is a light, yellowish metal, of the color of gold alloyed with silver. In hardness it is intermediate be- tween lead and gold ; it is very malleable, and can readily he hammered into leaves thinner than writing paper. It decomposes water rapidly, with liberation of hydrogen, melts at red heat, and burns to lime with a brilliant light and yellow flame, and is a poor conductor of electricity. Calcium fused with a large ex- cess of zinc forms an alloy, CaZn, s, which crystallizes in quadratic octahedrons of sp. gr. 6-37, and is readily decomposed by water. The equivalent of calcium is 20, its symbol Ca. The calcium light, commonly called Dmmmond light, is produced by the action of the oxyhydro- gen flame on perfectly pure lime, made free from silica by precipitation and afterword calcined and pressed into moulds. The most important salts of calcium will be treated of under their familiar names. CALCULATING MACHINES. Pinto, in the 4th century B. 0., invented a sliding square to solve the problem of two mean proportionate, and Nicomedes, three centuries afterward, in- vented his celebrated conchoid curve for solv-