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sawfly

(Encyclopedia)sawfly, common name for insects of several families of the order Hymenoptera, which also includes the ants, wasps, and bees. Sawflies are named for the two sawtoothed blades of the female's ovipositor...

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...

transit instrument

(Encyclopedia)transit instrument or transit, telescope devised to observe stars as they cross the meridian and used for determining time. Its viewing tube swings on a rigid horizontal axis restricting its movements...

Reno

(Encyclopedia)Reno rēˈnō [key], city (1990 pop. 133,850), seat of Washoe co., W Nev., on the Truckee River; inc. 1903. Tourism has been the major industry since gambling was legalized in Nevada in 1931. With its...

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...

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...

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...