SILLIMAN
1758
SIMCGB
While this is issuing from the orifice in the lower lip, the head of the worm is continually worked back and forth in such a manner that the thread is wound in spirals around the entire length of its body. There is formed in this manner one continuous thread of surprising length — being nearly four fifths of a mile long. The thread is matted together by a gummy substance. It is loosened in hot water, and the thread, united with those from four or five other cocoons, is unreeled. The process may occupy four days. There are several kinds of silk-producing larvas, but all others are inferior to the mulberry silkworm. The Ailantus silkworm and the Polyphemus moth, with the larvae of imported mulberry moths, are reared in America. The former feeds on oaks; the latter, the American silkworm, on the leaves of many different kinds of trees. There are various native silkworms. Many portions of the land would seem to be well adapted to silk-culture. China, Japan, Italy, France and India are the principal silk-producing countries. In the manufacture of silk the United States has made great strides in recent years. In 1905 there were 624 silk-mills, their capital $109,000,000. The gross value of products was $133,288,072. Pennsylvania and New Jersey are the principal silk-manufacturing states, Paterson, N. J.f sometimes being called the Lyons of America.
Silliman (stl'It-man), Benjamin, an American scientist, was born at Trumbull, Conn., Aug. 8, 1779. He studied at Yale College, and, after his appointment there as professor of chemistry, attended chemical lectures for three years at Philadelphia and for one year at Edinburgh and at London. He filled the chair of chemistry at Yale for about 50 years. He did much to make the study of chemistry and geology popular by public lectures through the country in 1808. He was the first president of the American Association of Geologists and Naturalists, and founded the American Journal of Science, known as Silliman's Journal, which he edited for 28 years. His textbook on chemistry was published in 1830. He died at New Haven, Conn., Nov. 24, 1864. See Life by^ Fisher.
Silo'am, a pool cut in the rocks southeast of Jerusalem and connected with it by an aqueduct.
Sil'vas or Sel'vas are the plains which center about the middle of the Amazon. They take their name from the thick jungle or forest with which they are clad. Their area is not far short of 1,000,000 square miles, one sixth of which is subject to periodical floods. No jungle is so thick as that of the selvas, where the sun hardly penetrates and mankind is represented only by a few Indians. Animal life, including jaguars, mon~ keys, birds, snakes and insects, is abundant $nd of great interest tp the naturalist,.
Sil'ver, one of the metals, ranking among the commoner metals next to gold in value. It is known by its white color, its luster and the ease with which it is worked. It is harder than gold and takes a fine polish. It is never found pure, being always mixed with a little copper or gold or some other metal, but in what is called its native state it is widely distributed. It is almost always found associated with gold, and all gold when mined contains more or less silver. The combinations of silver with other substances, as sulphur, oxygen and chlorine and especially in the ores of lead, form the largest part of the silver-ores found. In Europe the largest silver-mines are in Germany. Those of Norway have been worked since 1623, and in 1909 produced nearly $110,800. One piece of silver in Copenhagen Museum weighs 560 pounds, and another piece was dug out in Norway weighing over 1,500 pounds. Silver is also found in Spain, Italy, France and Turkey. The mines of silver in the United States are found mostly in Nevada, Arizona, California, Idaho, Utah, Colorado, New Mexico and Montana. Comstock Lode, a silver-mine in Nevada, probably is the most productive one ever worked. The silver-region of the western United States was discovered only in 1859, but now produces about one-ninth of the silver of the world, being $28,455,200 in 1909. The rich silver-mines of Mexico and Peru, worked by the Indians, were developed by the Spaniards after the conquests in the i6th century. Humboldt reports about 3,000 different mines in operation in Mexico, and in 1909 the production was valued at $38,450,100. Australasia is now added to the silver-producing countries, the yearly product of the silver-districts being $16,241,300.
Silver is one of the most useful of the metals, being used in coinage, plate and jewelry, and its compounds in photography, glass-staining etc. It is too soft to be used alone, and is generally mixed or alloyed with copper. Silver-coins in the United States contain one tenth of copper and nine tenths of silver. See METALLURGY. Consult Phillips's Gold and Silver.
Sim'coe, John Graves, was born in Northamptonshire, England, in 1752 and died in 1806. He was educated at Eton and at Mer-ton College, Oxford, and when 19 entered the army. His regiment took part at Bunker Hill in 1775. He was appointed lieutenant-governor of Upper Canada in 1792, and took up his residence at Newark near the mouth of the Niagara River. The whole population of the province then did not exceed 20,000. There were a few settlers at Kingston, York, Newark and at the front in the Bay of Quint6 district; and some roving bands of Indians. About two months after his arrival the first provincial parliament of Upper Canada met. It consisted of i§
