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pontoon

(Encyclopedia)pontoon, one of a number of floats used chiefly to support a bridge, to raise a sunken ship, or to float a hydroplane or a floating dock. Pontoons have been built of wood, of hides stretched over wick...

gas

(Encyclopedia)gas, in physics, one of the three commonly recognized states of matter, the other two being solid and liquid. A substance in the gaseous state has neither definite shape nor definite volume. Like liqu...

Apennines

(Encyclopedia)Apennines ăpˈənīnz [key], Ital. Appennino, mountain system, running the entire length of the Italian peninsula. It extends south c.840 mi (1,350 km) from the Cadibona Pass in Liguria, NW Italy, wh...

Dzungaria

(Encyclopedia)Dzungaria jo͝ongˈgärˈ [key], physical region (c.300,000 sq mi/777,000 sq km) of Xinjiang Uygur Autonomous Region, NW China. It is a largely steppe and semidesert basin surrounded by high mountains...

spark chamber

(Encyclopedia)spark chamber, in physics, device for recording the passage of elementary particles produced by reactions in a particle accelerator. Particles pass through a stack of metal plates or wire grids that a...

Wade, Abdoulaye

(Encyclopedia)Wade, Abdoulaye äbdo͞olīˈə wäd [key], 1926–, Senegalese political leader. He studied at several French universities, receiving (1970) a doctorate in law and economics from the Sorbonne, and wa...

boiler

(Encyclopedia)boiler, device for generating steam. It consists of two principal parts: the furnace, which provides heat, usually by burning a fuel, and the boiler proper, a device in which the heat changes water in...

osmosis

(Encyclopedia)osmosis ŏzmōˈsĭs [key], transfer of a liquid solvent through a semipermeable membrane that does not allow dissolved solids (solutes) to pass. Osmosis refers only to transfer of solvent; transfer o...

light

(Encyclopedia)light, visible electromagnetic radiation. Of the entire electromagnetic spectrum, the human eye is sensitive to only a tiny part, the part that is called light. The wavelengths of visible light range ...

Rocky Mountains

(Encyclopedia)Rocky Mountains, major mountain system of W North America and easternmost belt of the North American cordillera, extending more than 3,000 mi (4,800 km) from central N.Mex. to NW Alaska; Mt. Elbert (1...