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spring, in geology

(Encyclopedia)spring, in geology, natural flow of water from the ground or from rocks, representing an outlet for the water that has accumulated in permeable rock strata underground. Some of the water that falls as...

transpiration

(Encyclopedia)transpiration, in botany, the loss of water by evaporation in terrestrial plants. Some evaporation occurs directly through the exposed walls of surface cells, but the greatest amount takes place throu...

plumbing

(Encyclopedia)plumbing, piping systems inside buildings for water supply and sewage. The Romans had a highly developed plumbing system; water was brought to Rome by aqueducts and distributed to homes in lead pipesâ...

anhydride

(Encyclopedia)anhydride ănhīˈdrīd, –drĭd [key] [Gr.,=without water], chemical compound formed by removing water, H2O, from another compound; the anhydride can also react with water to form the original compo...

standpipe

(Encyclopedia)standpipe, tank or pipe for holding water in an elevated position to create pressure in a water supply system. For a tall building, where the pressure from the mains at street level is insufficient to...

irrigation

(Encyclopedia)irrigation, in agriculture, artificial watering of the land. Although used chiefly in regions with annual rainfall of less than 20 in. (51 cm), it is also used in wetter areas to grow certain crops, e...

Mead, George Herbert

(Encyclopedia)Mead, George Herbert mēd [key], 1863–1931, American philosopher and psychologist, b. South Hadley, Mass., grad. Oberlin, 1883, and Harvard, 1888, and studied in Leipzig and Berlin. He taught at the...

trench warfare

(Encyclopedia)trench warfare. Although trenches were used in ancient and medieval warfare, in the American Civil War, and in the Russo-Japanese War (1904–5), they did not become important until World War I. The i...

evaporimeter

(Encyclopedia)evaporimeter ĭvăpˌərĭmˈətər [key], instrument that measures the rate of evaporation of water into the atmosphere, sometimes called an atmometer. Evaporimeters are of two types, those that meas...

Pennsylvania

(Encyclopedia)CE5 Pennsylvania pĕnsəlv�ˈnyə [key], one of the Middle Atlantic states of the United States. It is bordered by New Jersey, across the Delaware River (E), Delaware (SE), Maryland (S), West Virg...