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W and Z particles

(Encyclopedia)W and Z particles, elementary particles that mediate, or carry, the fundamental force associated with weak interactions. The discovery of the W and Z particles at CERN near Geneva, Switzerland, in the...

spirit level

(Encyclopedia)spirit level, tool for determining whether a surface is horizontal. It consists essentially of a slightly bent transparent tube that is held in a frame. The tube contains some alcohol, ether, or simil...

loess

(Encyclopedia)loess lĕs, lōˈəs, Ger. lös [key], unstratified soil deposit of varying thickness, usually yellowish and composed of fine-grained angular mineral particles mixed with clay. It is found in many reg...

pinnacle

(Encyclopedia)pinnacle pĭnˈĭkəl [key], minor architectural motif of vertical tapering shape, usually crowning a pier, buttress, or gable. Although sometimes it appears in Renaissance design, as in the Certosa d...

tractor

(Encyclopedia)tractor, in agriculture, vehicle used to pull such equipment as plows, cultivators, and mowers; to power stationary devices such as saws and winches; and to push snowplows and earth-moving implements....

Malmstrom Air Force Base

(Encyclopedia)Malmstrom Air Force Base mälmˈstrəm, mălmˈ– [key], U.S. military installation, 3,573 acres (1,446 hectares), W central Mont., E of Great Falls; est. 1942. During World War II, it was the takeof...

crane, machine

(Encyclopedia)crane, hoisting machine for lifting heavy loads and transferring them from one place to another, ordinarily over distances of not more than 200 ft (60 m). Cranes have a long reach and can lift loads t...

McDonnell, James Smith

(Encyclopedia)McDonnell, James Smith, 1899–1980, American aviation pioneer, b. Denver, B.S. Princeton, 1921, M.S. Massachusetts Institute of Technology, 1925. He designed the Doodlebug (1929), a small monoplane, ...

altitude

(Encyclopedia)altitude, vertical distance of an object above some datum plane, such as mean sea level or a reference point on the earth's surface. It is usually measured by the reduction in atmospheric pressure wit...

Torrance

(Encyclopedia)Torrance, industrial and residential city (1990 pop. 133,107), Los Angeles co., SW Calif.; inc. 1921. It has large aircraft and electronics industries. Among its many manufactures are aircraft, electr...