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Torvalds, Linus Benedict

(Encyclopedia)Torvalds, Linus Benedict, 1969–, Finnish-American computer software engineer. A member of Finland's Swedish-speaking minority, he attended the Univ. of Helsinki (M.S., 1996), where he also taught. I...

thermodynamics

(Encyclopedia)thermodynamics, branch of science concerned with the nature of heat and its conversion to mechanical, electric, and chemical energy. Historically, it grew out of efforts to construct more efficient he...

Herschel

(Encyclopedia)Herschel hûrˈshəl [key], family of distinguished English astronomers. Sir William Herschel,Sir William Herschel, 1738–1822, born Friedrich Wilhelm Herschel, was a great pioneer in astronomy. Bor...

gram

(Encyclopedia)gram, abbr. g, unit of mass equal to 0.001 kilogram, the basic unit of mass in the metric system. The gram is the unit of mass in the cgs system. It is approximately equal to 0.035 avoirdupois ounce, ...

Byrom, John

(Encyclopedia)Byrom, John bīˈrəm [key], 1692–1763, English shorthand expert and poet, educated at Trinity College, Cambridge. He devised an early shorthand system, which he taught in Manchester. Although he co...

Brahmagupta

(Encyclopedia)Brahmagupta bräˌməgo͝opˈtə [key], c.598–c.660, Indian mathematician and astronomer. He was among the first to meaningfully discuss the concepts of zero and of negative numbers. He wrote in ver...

watershed

(Encyclopedia)watershed, elevation or divide separating the catchment area, or drainage basin, of one river system or group of river systems from another system or group of systems. The term is also often used syno...

Beer, George Louis

(Encyclopedia)Beer, George Louis, 1872–1920, American historian, b. Staten Island, N.Y. He was a tobacco importer for 10 years but also lectured on European history at Columbia from 1893 to 1897. After 1903 he de...

X-ray astronomy

(Encyclopedia)X-ray astronomy, study of celestial objects by means of the X rays they emit, in the wavelength range from 0.01 to 10 nanometers. X-ray astronomy dates to 1949 with the discovery that the sun emits X ...

All-American Canal

(Encyclopedia)All-American Canal, 80 mi (129 km) long, SE Calif.; part of the federal irrigation system of the Hoover Dam. Built between 1934 and 1940 across the Colorado Desert, the canal is entirely within the Un...