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mining

(Encyclopedia)mining, extraction of solid mineral resources from the earth. These resources include ores, which contain commercially valuable amounts of metals, such as iron and aluminum; precious stones, such as d...

methyl

(Encyclopedia)methyl mĕthˈəl [key], CH3, organic free radical or alkyl group derived from methane by the removal of one hydrogen atom. ...

Kozlov, Frol Romanovich

(Encyclopedia)Kozlov, Frol Romanovich frōl rəmäˈnəvĭch kŏzlŏfˈ [key], 1908–65, Soviet Communist leader. Early in his career he joined the Communist party and rose in the party organization. Kozlov reache...

drainage, in mining

(Encyclopedia)drainage, in mining, removal of water seeping into shafts and other underground mine workings from the surrounding ground. Unless seeping water is removed continually, it may endanger haulage and mini...

cornstarch

(Encyclopedia)cornstarch, material made by pulverizing the ground, dried residue of corn grains after preparatory soaking and the removal of the embryo and the outer covering. It is used as laundry starch, in sizin...

Swithin, Saint

(Encyclopedia)Swithin or Swithun, Saint both: swĭᵺˈən [key], fl. 860, English bishop of Winchester. He was buried, according to his wishes, outside his church, but his relics were later removed to the new cath...

Dillon, John Forrest

(Encyclopedia)Dillon, John Forrest, 1831–1914, American jurist, b. Montgomery co., N.Y., M.D. State Univ. of Iowa, 1850. He abandoned medical practice early in his career and was admitted to the Iowa bar in 1852....

cyst

(Encyclopedia)cyst, abnormal sac in the body, filled with a fluid or semisolid and enclosed in a membrane. Cysts can be congenital but are usually acquired, the most common locations being the skin and the ovaries....

Troup, George Michael

(Encyclopedia)Troup, George Michael, 1780–1856, governor of Georgia (1823–27), b. McIntosh Bluff, on the Tombigbee River, Ala. (then a part of Georgia). As governor, he was an extreme supporter of states' right...

tartar, dental

(Encyclopedia)tartar, dental, precipitate of saliva that accumulates around teeth at the gum line. Composed primarily of calcium salts, tartar forms as a hard brownish substance that irritates gums and causes them ...