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inclined plane

(Encyclopedia)CE5 Inclined plane inclined plane, simple machine, consisting of a sloping surface, whose purpose is to reduce the force that must be applied to raise a load. To raise a body vertically a force mu...

hardening

(Encyclopedia)hardening, in metallurgy, treatment of metals to increase their resistance to penetration. A metal is harder when it has small grains, which result when the metal is cooled rapidly. Sometimes small ar...

Gunpowder Plot

(Encyclopedia)Gunpowder Plot, conspiracy to blow up the English Parliament and King James I on Nov. 5, 1605, the day set for the king to open Parliament. It was intended to be the beginning of a great uprising of E...

grafting

(Encyclopedia)CE5 Two methods of grafting grafting, horticultural practice of uniting parts of two plants so that they grow as one. The scion, or cion, the part grafted onto the stock or rooted part, may be a s...

meteor shower

(Encyclopedia)meteor shower, increase in the number of meteors observed in a particular part of the sky. The trails of the meteors of a meteor shower all appear to be traceable back to a single point in the sky, kn...

Northumberland, John Dudley, duke of

(Encyclopedia)Northumberland, John Dudley, duke of, 1502?–1553, English statesman. The son of Edmund Dudley, minister of Henry VII, John was restored to his inheritance in 1512 after his father's attainder and ex...

locust, in zoology

(Encyclopedia)locust, in zoology, name for certain migratory members of the short-horned grasshopper family (Acrididae). Like other members of this family, locusts have antennae shorter than their bodies, song-prod...

Louis VII, king of France

(Encyclopedia)Louis VII (Louis the Young), c.1120–1180, king of France (1137–80), son and successor of King Louis VI. Before his accession he married Eleanor of Aquitaine. A controversy with Pope Innocent II ov...

xenon

(Encyclopedia)xenon zēˈnŏn [key] [Gr.,=strange], gaseous chemical element; symbol Xe; at. no. 54; at. wt. 131.293; m.p. −111.9℃; b.p. −107.1℃; density 5.86 grams per liter at STP; valence usually 0. Xeno...

Work Projects Administration

(Encyclopedia)Work Projects Administration (WPA), former U.S. government agency, established in 1935 by executive order of President Franklin Delano Roosevelt as the Works Progress Administration; it was renamed th...