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machine gun

(Encyclopedia)machine gun: see small arms.

(Encyclopedia)transmission, in automobiles, system of parts connecting the engine to the wheels. Suitable torque, or turning force, is generated by the engine only within a narrow range of engine speeds, i.e., rate...

chemical warfare

(Encyclopedia)chemical warfare, employment in war of incendiaries, poison gases, and other chemical substances. Ancient armies attacking or defending fortified cities threw burning oil and fireballs. A primitive ty...

automation

(Encyclopedia)automation, automatic operation and control of machinery or processes by devices, such as robots that can make and execute decisions without human intervention. The principal feature of such devices i...

governor, device

(Encyclopedia)governor, automatic device used to regulate and control such variables as speed or pressure in the functioning of an engine or other machine. A governor may be an electric, hydraulic, or mechanical de...

semaphore

(Encyclopedia)CE5 Positions of a railroad semaphore: (A) clear, (B) caution, (C) stop semaphore sĕmˈəfôrˌ [key], device for the visible transmission of messages. The marine semaphore, used by day between s...

nuclear strategy

(Encyclopedia)nuclear strategy, a policy for the use of nuclear weapons. The first atomic bombs were used in the context of the Allies' World War II policy of strategic bombing. Early in the cold war, U.S. policy w...

casting

(Encyclopedia)casting or founding, shaping of metal by melting and pouring into a mold. Most castings, especially large ones, are made in sand molds. Sand, mixed with a binder to hold it together, is pressed around...