Columbia Encyclopedia

Search results

500 results found

forestry

(Encyclopedia)forestry, the management of forest lands for wood, water, wildlife, forage, and recreation. Because the major economic importance of the forest lies in wood and wood products, forestry has been chiefl...

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...

hydrate

(Encyclopedia)hydrate hīˈdrāt [key], chemical compound that contains water. A common hydrate is the familiar blue vitriol, a crystalline form of cupric sulfate. Chemically, it is cupric sulfate pentahydrate, CuS...

thirst

(Encyclopedia)thirst, sensation indicating the body's need for water. Dry or salty food and dry, dusty air may induce such a sensation by depleting moisture in the mucous membranes of the mouth and throat. Relief t...

lock, canal

(Encyclopedia)lock, canal, stretch of water enclosed by gates, one at each end, built into a canal or river for the purpose of raising or lowering a vessel from one water level to another. A lock may also be built ...

Parker Dam

(Encyclopedia)Parker Dam, at the Ariz.–Calif. line, on the Colorado River; completed 1938. It is 320 ft (98 m) high and 856 ft (261 m) long. The dam impounds water for Los Angeles and other coastal cities, has a ...

Maracaibo, Lake

(Encyclopedia)Maracaibo, Lake, largest lake of South America, c.5,100 sq mi (13,210 sq km), NW Venezuela, extending c.110 mi (180 km) inland. A strait, 34 mi (55 km) long, connects it with the Gulf of Venezuela. Di...

temperature inversion

(Encyclopedia)temperature inversion, condition in which the temperature of the atmosphere increases with altitude in contrast to the normal decrease with altitude. When temperature inversion occurs, cold air underl...

Sierra Club

(Encyclopedia)Sierra Club, national organization in the United States dedicated to the preservation and expansion of the world's parks, wildlife, and wilderness areas. Founded (1892) in California by a group led by...

game laws

(Encyclopedia)game laws, restrictions on the hunting or capture of wild game, whether bird, beast, or fish. After the Norman Conquest (1066), England enacted stringent game laws, known as the Forest Laws, which mad...