slag By-product formed in smelting, welding, and other metallurgical and combustion processes from impurities in the metals or ores being treated.
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slalom ► slave trade I 1765
Slag consists mostly of mixed oxides of elements such as silicon, sulfur, phosphorus, and aluminum; ash; and products formed in their reactions with furnace linings and fluxing substances such as limestone. During smelting or refining, slag floats on the surface of the molten metal, pro¬ tecting it from oxidation (see oxidation-reduction) by the atmosphere and keeping it clean. Slag cools into a coarse aggregate used in certain con¬ cretes; it is used as a road-building material, as ballast, and as a source of available phosphate fertilizer.
slalom \'sla-bm\ Alpine skiing event in which competitors race one at a time down a zigzag or wavy course past a series of flags or markers called gates. The course is carefully designed to test the skier’s skill, tim¬ ing, and judgment. A skier who misses a gate is disqualified unless he or she returns and passes through it from the proper side. Men’s events use 55-75 gates, women’s 45-65.
The giant slalom has characteristies of both slalom and downhill skiing; giant-slalom gates are wider and set farther apart, and the course is longer than in the slalom. The supergiant slalom (“super-G”) is closer to downhill; its course is steeper and straighter than that of the other slalom events and features longer, more sweeping turns taken at higher speed.
slander See defamation
slang Nonstandard vocabulary of extreme informality, usually not lim¬ ited to any region. It includes newly coined words, shortened forms, and standard words used playfully out of their usual context. Slang is drawn from the vocabularies of limited groups: cant, the words or expressions coined or adopted by an age, ethnic, occupational, or other group (e.g., college students, jazz musicians); jargon, the shoptalk or technical termi¬ nology specific to an occupation; and argot, the cant and jargon used as a secret language by thieves or other criminals. Occupying a middle ground between standard and informal words accepted by the general public and the special words or expressions of these subgroups, slang often serves as a testing ground for words in the latter category. Many prove either useful enough to become accepted as standard or informal words or too faddish for standard use. Blizzard and okay have become standard, while conbobberation (“disturbance”) and tomato (“girl”) have been discarded. Some words and expressions have a lasting place in slang; for instance, beat it (“go away”), first used in the 16th century, has nei¬ ther become standard English nor vanished.
slapstick Comedy characterized by broad humour, absurd situations, and vigorous, often violent action. It took its name from a paddlelike device, probably introduced by 16th-century commedia dell'arte troupes, that produced a resounding whack when one comic actor used it to strike another. Slapstick comedy became popular in 19th-century music halls and vaudeville theatres and was carried into the 20th century by silent- movie comedians such as Charlie Chaplin, Harold Lloyd, and Mack Sen- nett’s Keystone Kops and later by Laurel and Hardy, the Marx Brothers, and the Three Stooges.
slate Fine-grained, clayey metamorphic rock that splits readily into thin slabs that have great tensile strength and durability. Some other rocks that occur in thin beds are improperly called slate because they can be used for roofing and similar purposes. True slates generally split not along the bedding plane but along planes of cleavage that may intersect the bedding plane at high angles. Slates may be black, blue, purple, red, green, or gray. Slate may be marketed either as dimension slate, used mainly for elec¬ trical panels, laboratory tabletops, roofing, and flooring, or as crushed slate, used on composition roofing, in aggregates, and as a filler.
Slater, Samuel (b. June 9, 1768, Belper, Derbyshire, Eng.—d. April 21, 1835, Webster, Mass., U.S.) British-born U.S. industrialist. Initially apprenticed to a partner of Richard Arkwright, he immigrated to the U.S. in 1789, where he reproduced versions of Arkwright’s spinning and card¬ ing machines from memory and in 1793 established the first successful American cotton mill at Pawtucket, R.I., the first of several plants. He founded the town of Slatersville, R.I. He is regarded as the founder of the U.S. cotton textile industry.
Slav \'slav\ Any member of the most numerous ethnic and linguistic body of peoples in Europe. They live chiefly in eastern and southeastern Europe but also extend across northern Asia to the Pacific. Slavs are cus¬ tomarily subdivided into eastern Slavs (Russians, Ukrainians, and Belaru¬ sians), western Slavs (Poles, Czechs, Slovaks, and Wends, or Sorbs), and southern Slavs (Serbs, Croats, Bulgarians, Slovenes, and Macedonians). Historically, western Slavs were integrated into western Europe; their societies developed along the lines of other western European nations. Eastern and southern Slavs suffered Mongol and Turkish invasions and evolved more autocratic, state-centred forms of government. Religion (mainly Eastern Orthodoxy and Roman Catholicism) divides Slavs, as does the use of the Cyrillic and Latin alphabets. In the Middle Ages, Slavic polities that left a rich cultural heritage developed in Bohemia, Poland, Croatia, Bosnia, Serbia, and Bulgaria, but, by the end of the 18th century, all these states had been absorbed by powerful neighbours (the Ottoman Empire, Austria, Hungary, Prussia, Russia). Eastern Slavic history often was marked by unsuccessful attempts to repel Asian invaders. In the 16th century, Muscovy (later Russia) embarked on a course of expansion across northern and central Asia that eventually made it the most powerful Slavic state. Pan-Slavism in the 19th century had some influence on the forma¬ tion of the new Slavic states after World War I, though Czechoslovakia and Yugoslavia—the two attempts to integrate different Slavic peoples into single polities—had both disintegrated by the end of the 20th cen¬ tury, one peacefully and the other violently.
Slave Acts, Fugitive See Fugitive Slave Aas
slave code In U.S. history, law governing the status of slaves, enacted by those colonies or states that permitted slavery. Slaves were considered property rather than persons. They had few legal rights: in court, their testimony was inadmissible in cases involving whites; they could make no contract nor own any property; they could not strike a white person, even if attacked by one; they could not be away from their owner’s pre¬ mises without permission; they could not assemble unless a white person was present; they could not be taught to read or write; and they were not permitted to marry. Offenders were subject to severe punishment, includ¬ ing whipping, branding, imprisonment, and death. See also black code.