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free silver

(Encyclopedia)free silver, in U.S. history, term designating the political movement for the unlimited coinage of silver. In 1896 free silver became the major issue of a presidential campaign when William Jennings...

genetic engineering

(Encyclopedia)CE5 Genetic engineering: Gene-splicing techniques genetic engineering, the use of various methods to manipulate the DNA (genetic material) of cells to change hereditary traits or produce biologica...

modem

(Encyclopedia)modem [modulator/demodulator], an external device or internal electronic circuitry used to transmit and receive digital data over a communications line normally used for analog signals. A modem attach...

Australian aborigines

(Encyclopedia)Australian aborigines, indigenous peoples of Australia. The first modern humans in Australia probably came from somewhere in Asia more than 40,000 years ago, most likely sometime between 55,000 and 10...

sunspots

(Encyclopedia)sunspots, dark, usually irregularly shaped spots on the sun's surface that are actually solar magnetic storms. The spots are darker because the temperature of the spots is lower than that of the surro...

United Mine Workers of America

(Encyclopedia)United Mine Workers of America (UMW), international labor union formed (1890) by the amalgamation of the National Progressive Union (organized 1888) and the mine locals under the Knights of Labor. It ...

Sharon, Ariel

(Encyclopedia)Sharon, Ariel ärˈēĕl shärōnˈ [key], 1928–2014, Israeli general and politician, b. Kfar Malal as Ariel Scheinerman. As a teenager he joined the Haganah, the underground Zionist military brigad...

poliomyelitis

(Encyclopedia)poliomyelitis pōˌlēōmīˌəlīˈtĭs [key], polio, or infantile paralysis, acute viral infection, mainly of children but also affecting older persons. Historically, there were three immunologic ty...

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...

pesticide

(Encyclopedia)pesticide, biological, physical, or chemical agent used to kill plants or animals that are harmful to people; in practice, the term pesticide is often applied only to chemical agents. Various pesticid...