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transmission

(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...

pottery

(Encyclopedia)pottery, the baked-clay wares of the entire ceramics field. For a description of the nature of the material, see clay. American art pottery flourished in the first half of the 20th cent., with wor...

lubrication

(Encyclopedia)lubrication, introduction of a substance between the contact surfaces of moving parts to reduce friction and to dissipate heat. A lubricant may be oil, grease, graphite, or any substance—gas, liquid...

hydraulic machine

(Encyclopedia)CE5 Hydraulic pressure: In any hydraulic device the pressure exerted by one piston is transmitted throughout the fluid. Since pressure equals force divided by area, a small force (F1) exerted on a ...

jet propulsion

(Encyclopedia)CE5 Types of jet engines: In the propeller-driven turbine a stream of high-velocity gases provides the power to drive the turbine and turn the propeller. In the jet-driven turbine the stream of gas...

horse racing

(Encyclopedia)horse racing, trials of speed involving two or more horses. It includes races among harnessed horses with one of two particular gaits, among saddled Thoroughbreds (or, less frequently, quarterhorses) ...

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...

locomotive

(Encyclopedia)locomotive, vehicle used to pull a train of unpowered railroad cars. Richard Trevithick, a British engineer and inventor, built and operated (1803–4) the first successful steam engine locomotive f...

glass

(Encyclopedia)glass, hard substance, usually brittle and transparent, composed chiefly of silicates and an alkali fused at high temperature. Glass has become invaluable in modern architecture, illumination, elect...

Adams, John, 2d President of the United States

(Encyclopedia)Adams, John, 1735–1826, 2d President of the United States (1797–1801), b. Quincy (then in Braintree), Mass., grad. Harvard, 1755. John Adams and his wife, Abigail Adams, founded one of the most di...