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brake, in technology

(Encyclopedia)CE5 Shoe brake CE5 Disk brake brake, in technology, device to slow or stop the motion of a mechanism or vehicle. The vacuum brake system, or vacuum brake, depends upon the use of a vacuum to ...

viscosity

(Encyclopedia)viscosity, resistance of a fluid to flow. This resistance acts against the motion of any solid object through the fluid and also against motion of the fluid itself past stationary obstacles. Viscosity...

White, Elijah

(Encyclopedia)White, Elijah, 1806–79, American missionary in the Oregon country. A physician, he left Boston in 1836 to join the Methodist mission established by Jason Lee. After friction with his associates, he ...

meteor

(Encyclopedia)meteor, appearance of a small particle flying through space that interacts with the earth's upper atmosphere. While still outside the atmosphere, the particle is known as a meteoroid. Countless meteor...

detonator

(Encyclopedia)detonator dĕˈtənāˌtər [key], type of explosive that reacts with great rapidity and is used to set off other, more inert explosives. Fulminate of mercury mixed with potassium chlorate is a common...

Alexander II, king of Scotland

(Encyclopedia)Alexander II, 1198–1249, king of Scotland (1214–49), son and successor of William the Lion. He joined the English barons in their revolt against King John of England in 1215. Though he made his pe...

canker

(Encyclopedia)canker, small sore on the inside of the mouth. A canker appears as a shallow, whitish ulcer surrounded by a thin, red area. It is tender, sometimes painful, and may occur singly or as one of a group o...

atomic force microscope

(Encyclopedia)atomic force microscope (AFM), device that uses a spring-mounted probe to image individual atoms on the surface of a material, first developed by Gerd Binnig in 1986. Unlike the scanning tunneling mic...

meteorite

(Encyclopedia)meteorite, meteor that survives the intense heat of atmospheric friction and reaches the earth's surface. Because of the destructive effects of this friction, only the very largest meteors become mete...

Repplier, Agnes

(Encyclopedia)Repplier, Agnes rĕpˈlēr [key], 1858–1950, American essayist, b. Philadelphia. Her essays, esteemed for their scholarship and wit, are collected in several volumes, including Books and Men (1888),...