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Frasch process

(Encyclopedia)Frasch process fräsh [key] [for Herman Frasch, the German-American chemist who devised it], process for the extraction of sulfur from subsurface deposits. Three pipes, one inside another, are sunk to...

Siloam

(Encyclopedia)Siloam sīlōˈəm [key], pool, SW corner of Jerusalem in the Kidron valley, mentioned in the Bible. A nearby 1,700-foot-long (518 m) tunnel, dating from the time of Hezekiah, diverted water underneat...

calcium chloride

(Encyclopedia)calcium chloride, CaCl2, chemical compound that is crystalline, lumpy, or flaky, is usually white, and is very soluble in water. The anhydrous compound is hygroscopic; it rapidly absorbs water and is ...

detergent

(Encyclopedia)detergent dētûrˈjənt, dĭ– [key], substance that aids in the removal of dirt. Detergents act mainly on the oily films that trap dirt particles. The detergent molecules have a hydrocarbon portion...

grebe

(Encyclopedia)grebe grēb [key], common name for swimming birds found on or near quiet waters in most parts of the world. Grebes resemble the loon and the duck; they have short wings, vestigial tails, and long, ind...

kingfisher

(Encyclopedia)kingfisher, common name for members of the family Alcedinidae, essentially tropical and subtropical land birds, related to the bee-eaters, rollers, and todies. Kingfishers have chunky bodies, short ne...

pile

(Encyclopedia)pile, post of timber, steel, or concrete used to support a structure. Vertical piles, or bearing piles, the most common form, are generally needed for the foundations of bridges, docks, piers, and bui...

mucilage

(Encyclopedia)mucilage myo͞oˈsəlĭj [key], thick, glutinous substance, related to the natural gums, comprised usually of protein, polysaccharides, and uranides. It swells but does not dissolve in water. Mucilage...

cofferdam

(Encyclopedia)cofferdam, temporary barrier for excluding water from an area that is normally submerged. Made commonly of wood, steel, or concrete sheet piling (see pile), cofferdams are used in constructing the fou...

All-American Canal

(Encyclopedia)All-American Canal, 80 mi (129 km) long, SE Calif.; part of the federal irrigation system of the Hoover Dam. Built between 1934 and 1940 across the Colorado Desert, the canal is entirely within the Un...