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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...

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...

ocean

(Encyclopedia)ocean, interconnected mass of saltwater covering 70.78% of the surface of the earth, often called the world ocean. It is subdivided into four (or five) major units that are separated from each other i...

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...

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...

heat exhaustion

(Encyclopedia)heat exhaustion, condition caused by overexposure to sunlight or another heat source and resulting in dehydration and salt depletion, also known as heat prostration. The symptoms are severe headaches,...

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...