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well

(Encyclopedia)well, aperture in the earth's surface through which substances in a natural underground reservoir, such as water, gas, oil, salt, and sulfur, can flow or be pumped to the surface. In the United States...

compressed air

(Encyclopedia)compressed air, air whose volume has been decreased by the application of pressure. Air is compressed by various devices, including the simple hand pump and the reciprocating, rotary, centrifugal, and...

eccentric

(Encyclopedia)eccentric, in mechanics, device for changing rotary to back-and-forth motion. A disk is mounted off center on a shaft. One flat, open, circular end of a rod fits around the edge of the disk; the other...

kiln

(Encyclopedia)kiln kĭl, kĭln [key], furnace for firing pottery and enamels, for making brick, charcoal, lime, and cement, for roasting ores, and for drying various substances (e.g., lumber, chemicals). Kilns may ...

vacuum

(Encyclopedia)vacuum, theoretically, space without matter in it. A perfect vacuum has never been obtained; the best human-generated vacuums contain less than 100,000 gas molecules per cc, compared to about 30 billi...

compressor

(Encyclopedia)compressor, machine that decreases the volume of air or other gas by the application of pressure. Compressor types range from the simple hand pump and the piston-equipped compressor used to inflate ti...

trunkfish

(Encyclopedia)trunkfish, any member of a family of fishes, Ostraciidae, also called boxfishes, that have short triangular bodies covered by firmly united hexagonal bony plates. Only the jaw, the bases of the fins, ...

hoe

(Encyclopedia)hoe, usually a flat blade, variously shaped, set in a long wooden handle and used primarily for weeding and for loosening the soil. It was the first distinctly agricultural implement. The earliest hoe...

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...

incinerator

(Encyclopedia)incinerator, furnace for burning refuse. The older and simpler kind of incinerator was a brick-lined cell with a metal grate over a lower ash pit, with one opening in the top or side for loading and a...