Vase with relief decoration by Emile Galle, c. 1895; in the Victoria and Albert Museum, London
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730 i Gallipoli Campaign ► Galveston
west of Istanbul. First colonized by the Greeks, it was the site of an impor¬ tant Byzantine fortress. It became the first Ottoman conquest in Europe (c. 1356) and was used as a naval base because of its strategic importance for the defense of Constantinople (Istanbul). Much of the town was destroyed in World War I (1914-18) during the Dardanelles Campaign. Historic sites include a 14th-century Ottoman castle and the tombs of Thracian kings.
Gallipoli Campaign See Dardanelles Campaign
gallium Metallic chemical element, chemical symbol Ga, atomic num¬ ber 31. Silvery white and soft enough to be cut with a knife, gallium has an unusually low melting point (about 30 °C [86 °F]), which allows it to liquefy in the palm of the hand. The liquid metal clings to or wets glass and similar surfaces. Gallium expands on solidification and supercools readily, remaining liquid at temperatures as low as 0 °C (32 °F). In vari¬ ous combinations with aluminum, indium, phosphorus, arsenic, and antimony, it forms compounds (e.g., gallium arsenide and indium gallium arsenide phosphide) with valuable semiconductor and optoelectronic properties; some of these compounds form the basis for such electronic devices as light-emitting diodes and semiconductor lasers.
Galloway, Joseph (b. c. 1731, West River, Md.—d. Aug. 29, 1803, Watford, Hertfordshire, Eng.) American colonial lawyer and legislator. Entering law practice in Philadelphia in 1747, Galloway won a reputation by pleading cases before the Supreme Court of Pennsylvania before he was 20. He was elected to the colonial legislature in 1756 and served as speaker from 1766 to 1775. A loyalist, he opposed the independence of the colonies; his plan for a peaceful resolution of the conflict with Brit¬ ain was narrowly rejected by the Continental Congress. During the Ameri¬ can Revolution Galloway joined the British army under William Howe, becoming a civil administrator of Philadelphia during the British occu¬ pation of the city. When the Continental Army reentered Philadelphia in 1778, he fled to England.
gallstone Mass of crystallized substances that forms in the gallbladder. The most common type occurs when the liver secretes bile with too much cholesterol to stay in solution. Liver damage, chronic gallbladder disease, or biliary-tract cancer may predispose one to stone formation. In the gall¬ bladder, stones may cause inflammation or produce no symptoms. A stone obstructing the bile duct causes severe pain (biliary colic). Gallstones usually must be removed with the gallbladder or broken up with ultra¬ sound. In some cases a stone can be treated by giving the patient bile salts, which help redissolve cholesterol. If the gallbladder must be removed, laparoscopy is the method of choice.
Gallup, George (Horace) (b. Nov. 18, 1901, Jefferson, Iowa, U.S.—d. July 26, 1984, Tschingel, Switz.) U.S. public-opinion statisti¬ cian. He taught journalism at Drake University and Northwestern Uni¬ versity until 1932, when a New York advertising firm hired him to conduct public-opinion surveys for its clients. He became a pioneer in the scien¬ tific sampling of public opinion, and his Gallup Poll, as well as other public-opinion polls, gained credibility after correctly forecasting the 1936 presidential victory of Franklin D. Roosevelt. Gallup founded the American Institute of Public Opinion (1935), the British Institute of Pub¬ lic Opinion (1936), and the Audience Research Institute (1939).
Galsworthy Vgolz-.wor-theV John (b. Aug. 14, 1867, Kingston Hill, Surrey, Eng.—d. Jan. 31, 1933, Grove Lodge, Hampstead) English nov¬ elist and playwright. Galsworthy gave up a law career to become a writer, and many of his works have legal themes. He published several works before The Man of Property (1906), the first novel of The Forsyte Saga (completed 1922). The family chronicle by which he is chiefly remem¬ bered, it consists of three novels linked by two interludes. He continued the story of the Forsytes in three further novels collected in A Modern Comedy (1929). His plays, written in a naturalistic style, usually exam¬ ine a controversial ethical or social problem; they include The Silver Box (1906), Strife (1909), Justice (1910), and Loyalties (1922). He won the Nobel Prize for Literature in 1932.
Galt, Sir Alexander Tilloch (b. Sept. 6, 1817, London, Eng.—d. Sept. 19, 1893, Montreal, Que., Can.) British-Canadian statesman. He immigrated to Lower Canada (later Quebec) in 1835 and worked for the British-American Land Co., serving as high commissioner from 1844 to 1855. He entered politics in 1849 as an independent member for Sher¬ brooke county in the legislature of the united province of Canada. He resigned from the legislature in 1850 but was reelected for Sherbrooke
town in 1853. He maintained that seat and remained leader of the English- speaking minority until 1872. As finance minister (1858-62, 1864-67), he advocated federation; following the creation of the Dominion of Canada, he became the first finance minister of the Dominion government (1867-68). After retiring from Parliament in 1872, he advocated Cana¬ dian independence. From 1880 to 1883 he served as the first Canadian high commissioner in London.
Gallon, Sir Francis (b. Feb. 16, 1822, near Sparkbrook, Birmingham,
Warwickshire, Eng.—d. Jan. 17, 1911, Grayshott House, Haslemere, Surrey) British explorer, anthropolo¬ gist, and eugenicist. Galton, a cousin of Charles Darwin, studied medicine at Cambridge University but never took a degree. As a young man he traveled widely in Europe and Africa, making useful contributions in zoology and geography. He was among the first to recognize the implications of Darwin’s theory of evolution, eventually coining the word eugenics to denote the science of planned human betterment through selective mating. His aim was the creation not of an aristocratic elite but of a population consisting entirely of superior men and women. He also wrote important works on human intelligence, fingerprinting, applied statistics, twins, blood trans¬ fusions, criminality, meteorology, and measurement.
Sir Francis Galton, detail of an oil painting by G. Graef, 1882; in the National Portrait Gallery, London.
COURTESY OF THE NATIONAL PORTRAIT GALLERY, LONDON
Galut See Diaspora
Galvani \gal-'va-ne\, Luigi (b. Sept. 9, 1737, Bologna, Papal States—d. Dec. 4, 1798, Bologna, Cisalpine Republic) Italian physician and physicist. His early research focused on comparative anatomy, includ¬ ing the structure of kidney tubules and the middle ear. His developing interest in electricity was inspired by the fact that dead frogs underwent convulsions when attached to an iron fence to dry. He experimented with muscular stimulation by electrical means, using an electrostatic machine and a Leyden jar, and from the early 1780s animal electricity remained his major field of investigation. His discoveries led to the invention of the voltaic pile, a kind of battery that makes possible a constant source of current electricity.
galvanizing Protection of iron or steel against exposure to the atmo¬ sphere and consequent rusting by application of a zinc coating. Properly applied, galvanizing may protect from atmospheric corrosion for 15-30 years or more. If the coating is damaged, the iron or steel continues to be protected by sacrificial corrosion, a phenomenon in which atmospheric oxidation spares the iron and affects the zinc (as long as it lasts). See also TERNEPLATE.
galvanometer V.gal-vo-'na-mo-toA Instrument for measuring small electric currents by deflection of a moving coil. A common galvanometer consists of a light coil of wire suspended from a metallic ribbon between the poles of a permanent magnet. As current passes through the coil, the magnetic field it produces reacts with the magnetic field of the permanent magnet, producing a torque. The torque causes the coil to rotate, moving an attached needle or mirror. The angle of rotation, which provides a measure of the current flowing in the coil, is measured by the movement of the needle or by the deflection of a beam of light reflected from the mirror.