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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...

electrolyte

(Encyclopedia)electrolyte ĭlĕkˈtrəlītˌ [key], electrical conductor in which current is carried by ions rather than by free electrons (as in a metal). Electrolytes include water solutions of acids, bases, or s...

Crookes tube

(Encyclopedia)Crookes tube, device invented by Sir William Crookes (c.1875) consisting essentially of a sealed glass tube from which nearly all the air has been removed and through the walls of which are passed two...

Evans, Oliver

(Encyclopedia)Evans, Oliver, 1755–1819, American inventor, b. near Newport, Del. He joined his brothers in a flour-milling business in Wilmington, and after studying similar earlier devices, he developed, install...

hypertrophy

(Encyclopedia)hypertrophy hīpûrˈtrəfē [key], enlargement of a tissue or organ of the body resulting from an increase in the size of its cells. Such growth accompanies an increase in the functioning of the tiss...

Hasan

(Encyclopedia)Hasan häsänˈ [key], c.625–c.669; son of Ali and Fatima (daughter of Muhammad the Prophet). When Ali was killed in 661, Hasan became caliph, but he was not strong enough to withstand the threat of...

homogenization

(Encyclopedia)homogenization həmŏjˌənəzāˈshən [key], process in which a mixture is made uniform throughout. Generally this procedure involves reducing the size of the particles of one component of the mixtu...

harpoon

(Encyclopedia)harpoon härpo͞onˈ [key], weapon used for spearing whales and large fish. The early type was a flat triangular piece of metal with barbed edges and a socket for attaching a wooden handle, to the end...

amphictyony

(Encyclopedia)amphictyony ămfĭkˈtēōˌnē, –ŏˌnē, –ənēˌ [key], in ancient Greece, a league connected with maintaining a temple or shrine. There were a number of these, but by far the most important wa...

flint, mineral

(Encyclopedia)flint, variety of quartz that commonly occurs in rounded nodules and whose crystal structure is not visible to the naked eye. Flint is dark gray, smoky brown, or black in color; pale gray flint is cal...