Columbia Encyclopedia

Search results

500 results found

skywriting

(Encyclopedia)skywriting, advertising medium in which aircraft spell out trade names and sales slogans in the sky by means of the controlled emission of thick smoke. The technique was first developed (1922) by J. C...

Tannenberg

(Encyclopedia)Tannenberg täˈnənbĕrkˌ [key], Pol. Stębark, village, Warmińsko-Mazurskie prov., NE Poland, near Olsztyn. Formerly in East Prussia, it was transferred (1945) by the Potsdam Conference to Polish ...

spring, in mechanics

(Encyclopedia)spring, in mechanics, any of several elastic devices used variously to store and to furnish energy, to absorb shock, to sustain the pressure between contacting surfaces, and to resist tensional or com...

surface tension

(Encyclopedia)surface tension, tendency of liquids to reduce their exposed surface to the smallest possible area. A drop of water, for example, tends to assume the shape of a sphere. The phenomenon is attributed to...

weather

(Encyclopedia)weather, state of the atmosphere at a given time and place with regard to temperature, air pressure (see barometer), wind, humidity, cloudiness, and precipitation. The term weather is restricted to co...

steam engine

(Encyclopedia)CE5 Steam engine steam engine, machine for converting heat energy into mechanical energy using steam as a medium, or working fluid. When water is converted into steam it expands, its volume increa...

stimulant

(Encyclopedia)stimulant, any substance that causes an increase in activity in various parts of the nervous system or directly increases muscle activity. Cerebral, or psychic, stimulants act on the central nervous s...

poison

(Encyclopedia)poison, any agent that may produce chemically an injurious or deadly effect when introduced into the body in sufficient quantity. Some poisons can be deadly in minute quantities, others only if relati...

nail, in anatomy

(Encyclopedia)nail, in anatomy, the horny outgrowth shielding the tip of the finger and the toe in humans and most other primates. The nail consists of dead cells pushed outward by dividing cells in the root, a fol...

Gregory XII

(Encyclopedia)Gregory XII, c.1327–1417, pope (1406–15), a Venetian named Angelo Correr; successor of Innocent VII. As a condition of election, Gregory promised to do everything possible to end the Great Schism,...