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spectroscope

(Encyclopedia)spectroscope, optical instrument for producing spectral lines and measuring their wavelengths and intensities, used in spectral analysis (see spectrum). When a material is heated to incandescence it e...

electric shock

(Encyclopedia)electric shock, effect of the passage of a current of electricity through the body. Fatality may result from shocks of from 1 to 2 amperes and 500 to 1,000 volts. However, the effect of electric shock...

fertilization

(Encyclopedia)CE5 Fertilization of an egg cell fertilization, in biology, process in the reproduction of both plants and animals, involving the union of two unlike sex cells (gametes), the sperm and the ovum, f...

classical swine fever

(Encyclopedia)classical swine fever or hog cholera, acute, highly infectious viral disease of swine, historically perhaps the most serious disease of swine in North America. It is characterized by dullness and list...

rabies

(Encyclopedia)rabies hīˌdrəfōˈbēə [key], acute viral infection of the central nervous system in dogs, bats, foxes, raccoons, skunks, and other animals, and in humans. The virus is transmitted from an animal ...

photographic processing

(Encyclopedia)photographic processing, set of procedures by which the latent, or invisible, image produced when a photographic film is exposed to light is made into a permanent visible image. The negative may b...

searchlight

(Encyclopedia)searchlight, device, usually swiveled, using a lens and reflecting surface to direct a powerful beam of light of nearly parallel rays. In 1892 such apparatus was used along the English Channel in coas...

senility

(Encyclopedia)senility sənilˈətē [key], deterioration of body and mind associated with old age. Indications of old age vary in the time of their appearance. Stooped posture, wrinkled skin, decrease in muscle st...

Vertov, Dziga

(Encyclopedia)Vertov, Dziga, 1896–1954, Soviet filmmaker, pseudonym of Denis Kaufman. Vertov introduced the idea of “Kino-Pravda” (or cinéma vérité), which was extremely influential worldwide, affecting ci...

viscosity

(Encyclopedia)viscosity, resistance of a fluid to flow. This resistance acts against the motion of any solid object through the fluid and also against motion of the fluid itself past stationary obstacles. Viscosity...