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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...

energy, sources of

(Encyclopedia)energy, sources of, origins of the power used for transportation, for heat and light in dwelling and working areas, and for the manufacture of goods of all kinds, among other applications. The develop...

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...

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...

Great Lakes, North America

(Encyclopedia)Great Lakes, group of five freshwater lakes, central North America, creating a natural border between the United States and Canada and forming the largest body of freshwater in the world, with a combi...

hydrotherapy

(Encyclopedia)hydrotherapy, use of water in the treatment of illness or injury. Although the medicinal and hygienic value of water was recognized by the early Greeks, hydrotherapy attained its widest use in the 18t...

mercury poisoning

(Encyclopedia)mercury poisoning, tissue damage resulting from exposure to more than trace amounts of the element mercury or its compounds. Elemental mercury (the silver liquid familiar from thermometers) is the mos...

Mexico, city, Mexico

(Encyclopedia)Mexico or Mexico City, Span. Ciudad de México (Méjico), city (1990 pop. 8,236,960; 1991 met. area est. 20,899,000), central Mexico, capital and largest city of Mexico. The city has been the met...