other properties that differ from those of nonelectrolytes. Solutions are involved in most chemical reactions, refining and purification, industrial processing, and biological processes.
Solutrean \s9-1ii-tre-9n\ industry Short-lived stone-tool industry that flourished 17,000-21,000 years ago in southwestern France (e.g., at La Solutre and Laugerie-Haute) and in nearby areas. The industry is of spe¬ cial interest because of its particularly fine workmanship. In addition to burins (chisel-like tools), scrapers, and borers, the Solutrean industry exhibits blades formed in the shape of laurel or willow leaves and vari¬ ous shouldered points. Some implements are so fine as to be useless as tools and may instead have been luxury items.
Solvay process \'sal-,va\ or ammonia-soda process Modem method of manufacturing sodium carbonate (soda ash), devised and com¬ mercialized in Belgium by Ernest Solvay (1838-1922). Common salt (sodium chloride) is treated with ammonia and then carbon dioxide, under carefully controlled conditions, to form sodium bicarbonate and ammo¬ nium chloride. When heated, the bicarbonate yields sodium carbonate, the desired product; the ammonium chloride is treated with lime to produce ammonia (for reuse) and calcium chloride. The process proved of great commercial value, since large quantities of soda ash are used in making glass, detergents, and cleansers. See also caustic soda.
solvent Substance, ordinarily a liquid, in which other materials dissolve to form a solution. Polar solvents (e.g., water) favour formation of ions; nonpolar ones (e.g., hydrocarbons) do not. Solvents may be predominantly acidic, predominantly basic, amphoteric (both), or aprotic (neither). Organic compounds used as solvents include aromatic compounds and other hydrocarbons, alcohols, esters, ethers, ketones, amines, and nitrated and halogenated hydrocarbons. Their chief uses are as media for chemi¬ cal syntheses, as industrial cleaners, in extractive processes, in pharma¬ ceuticals, in inks, and in paints, varnishes, and lacquers.
Solway Firth Inlet of the Irish Sea. On the border between northwest¬ ern England and southwestern Scotland, it extends inland for 38 mi (61 km). It is a traditional boundary between the two countries. Hadrian's Wall terminates on its southern shore.
Solzhenitsyn V.sol-zhs-'net-sinV Aleksandr (Isayevich) (b. Dec. 11, 1918, Kislovodsk, Russia) Russian novelist and historian. He fought in World War II but was arrested in 1945 for criticizing Joseph Stalin. He spent eight years in prisons and labour camps and three more in enforced exile. With One Day in the Life of Ivan Denisovich (1962), based on his labour-camp experiences, he emerged as an eloquent opponent of gov¬ ernment repression. He was forced to publish later works abroad, includ¬ ing The First Circle (1968), Cancer Ward (1968), and August 1914 (1971). Publication of the first volume of The Gulag Archipelago (1973), one of the greatest works in Russian prose, resulted in his being charged with treason. Expelled from the Soviet Union in 1974, he lived in the U.S., enjoying worldwide fame, until 1994, when he returned home. In the late 1980s glasnost brought renewed access to his work in Russia but also a loss of interest in it and in the prophetic role he claimed for himself in Russian history. He was awarded the Nobel Prize for Literature in 1970.
soma In ancient Indian religion, an unidentified plant, the juice of which was an offering of the Vedic sacrifices. Its stalks were pressed, and its juice, filtered through wool, was mixed with water and milk. After being offered as a libation to the gods, the remainder of the soma was consumed by the priests and the sacrificer. It was highly valued for its exhilarating, probably hallucinogenic, effect. The plant was believed to have been delivered to the earth from heaven by an eagle. The personified deity Soma was the master of plants, healer of disease, and bestower of riches. See also Vedic religion.
Somali \s9-'ma-lez\ Any member of a large group of people occupying all of Somalia and parts of Djibouti, Ethiopia, and Kenya. Their language is of the Cushitic branch of the Afroasiatic family. Numbering more than seven million, the Somalis are divided into northern, central, and south¬ ern groups. All have been Muslim since at least the 14th century. They are primarily nomadic herdsmen who, because of intense competition for scarce resources, have been extremely individualistic and frequently involved in blood feuds or wars with neighbouring clans or peoples. A second category of Somalis are the townspeople and agriculturalists of the urban centres, especially along the coast of the Horn of Africa, many of whom act as commercial middlemen between the Arab world and the nomads of the interior.
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Somalia ► sonar I 1783
Somalia Country, eastern Africa. Located in the Horn of Africa, it stretches from the Equator to the Red Sea. Area: 246,000 sq mi (637,000 sq km). Population (2005 est.): 8,228,000 (excluding an estimated 400,000
cial; predominantly Sunni). Currency:
Somali shilling. Much of Somalia is semidesert. The central and southern regions are flat, while the northern region rises to form rugged mountain ranges. Only a tiny proportion of its land is arable, though more than half is grazeable. Somalia has a developing mixed economy based largely on livestock and agriculture. It is one of the poorest countries in the world. Muslim Arabs and Persians first established trading posts along the coasts in the 7th-10th centuries. By the 10th century Somali nomads occupied the area inland from the Gulf of Aden, and the south and west were inhabited by various groups of pastoral Oromo peoples. Intensive European explo¬ ration began after the British occupation of Aden in 1839, and in the late 19th century Britain and Italy set up protectorates in the region. During World War II the Italians invaded British Somaliland (1940); a year later British troops retook the area. Britain administered the region until 1950, when Italian Somaliland became a UN trust territory. In 1960 it was united with the former British Somaliland, and the two became the independent Republic of Somalia. Since then it has suffered political and civil strife, including military dictatorship, civil wars, drought, and famine. No effec¬ tive central government has existed since the early 1990s. In 1991 a Repub¬ lic of Somaliland was proclaimed by a breakaway group on territory corresponding to the former British Somaliland. It did not receive interna¬ tional recognition, but it operated more smoothly than the area of tradi¬ tional Somalia. A UN peacekeeping force intervened in 1992 to secure food supplies; fighting continued, and the peacekeeping force left in 1995. The country subsequently remained in turmoil.
Somaliland Vso-'ma-le-.landX Historical name for the region of eastern Africa between the Equator and the Gulf of Aden that includes Somalia, Djibouti, and southeastern Ethiopia. It has an area of about 300,000 sq mi (777,000 sq km). The region probably formed part of the “Land of Punt” known to the ancient Egyptians. Between the 7th and 12th centu¬ ries, Muslim traders from Arabia and Iran settled on the coast and formed sultanates. The nomadic Somali, who occupied the northern part of the country between the 10th and 15th centuries, adopted Islam and served in their armies. Gradually the sultanates themselves came under Somali control. In the late 19th century, France, Italy, and Britain partitioned the region among themselves. In 1960 British Somaliland and Italian Somali¬ land were united to form the Republic of Somalia. French Somaliland
became independent as the Republic of Djibouti in 1977. In 1991 British Somaliland announced that it was becoming an independent state, the Republic of Somaliland; it was not internationally recognized.
somatotropin See growth hormone
Somerset Administrative (pop., 2001: 498,093), geographic, and his¬ toric county, southwestern England. Its county seat is Taunton. The remains of prehistoric villages have been found in the region. The Romans mined lead and built villas there; from the 7th century ad, Somerset formed the westernmost part of the kingdom of Wessex. A large part of western Somerset is made up of Exmoor National Park, and long stretches of coastline are protected. It is mainly an agricultural county and is known for its cider. Tourism draws visitors to its Bristol Channel resorts and his¬ toric mansions.