GALVANI 



2369 



GALVANOMETER 



biology and anthropology. He was educated 

 at Birmingham and Trinity College, Cam- 

 bridge. After spending about two years in the 

 Sudan, studying native types, he started on a 

 journey of exploration through Damaraland 

 and the Ovampo country in Southwest Africa. 

 His published account of his travels brought 

 him the gold medal of the Royal Geographical 

 Society. Becoming interested in meteorology, 

 Galton suggested many important theories and 

 published extensive weather charts and articles 

 on anti-cyclones. 



On the subject of heredity he held advanced 

 views and boldly advocated the checking of 

 the birth rate of the unfit by suitable selec- 

 tion of parents. He was the first to use the 

 term eugenics, which has since been universally 

 adopted. Galton was singularly versatile, 

 quick, yet thorough, and an enthusiastic worker. 

 His notable publications are Hereditary Genius 

 Its Laws and Consequences; Inquiries into 

 Human Faculty and its Development and 

 Natural Inheritance. Honorary degrees were 

 bestowed on him by Oxford and Cambridge 

 universities, and in 1909 he received knight- 

 hood. See ANTHROPOLOGY; HEREDITY; EU- 

 GENICS. 



GALVANI, gahlvah'ne, LUIGI (1737-1798), 

 an Italian physiologist and anatomist, the dis- 

 coverer of galvanism, so named in his honor. 

 He was born at Bologna, studied medicine 

 there, and in 1762 began to practice. In. 1765 

 he became lecturer on anatomy at the Univer- 

 sity of Bologna, which position he held until 

 the year before his death, when he was 

 deprived of his professorship because of his 

 refusal to take the oath of allegiance to the 

 Cisalpine Republic. Just before his death he 

 was reinstated. 



His celebrated discoveries relative to the 

 effect of electricity upon animal muscles began 

 with the observation of the accidental contact 

 of the dissected legs of a frog with a scalpel 

 which was itself in contact with an electric 

 machine. The results of his experiments were 

 published in 1791. See ELECTRIC BATTERY; 

 GALVANISM. 



GALVAN'IC BATTERY, the old name for 

 electric battery. It was formerly supposed that 

 the electric current produced by chemical action 

 was different from that produced by friction, 

 and the name galvanic was given to electric 

 batteries in honor of Luigi Galvani (which see), 

 the discoverer of the fact that an electric cur- 

 rent could be produced by chemical action. 

 When it was learned that the current generated 

 149 



by a battery was of the same nature as that 

 generated by friction, the term was discarded. 

 See ELECTRIC BATTERY; GALVANISM. 



GAL'VANISM, a term formerly applied to 

 an electric current and its effects when the cur- 

 rent is produced by an electric battery. Orig- 

 inally the term was used to distinguish elec- 

 tricity produced by an electric battery from 

 that produced by an electrical machine, but 

 after it was discovered that the electricity of 

 an electric battery and that of an electrical 

 machine are one and the same, galvanism fell 

 into disuse. The name is derived from that of 

 an Italian scientist, Luigi Galvani (which see). 

 See ELECTRICITY; ELECTRIC BATTERY. 



GAL'VANIZED IRON, a name commonly 

 applied to thin sheets of iron that have been 

 coated with zinc as a protection against rust. 

 The process is not in any way galvanic, but 

 consists of first cleaning the iron in a warm 

 solution of sulphuric or hydrochloric acid, and 

 then immersing it in a bath of molten zinc 

 and sal ammoniac. As the zinc cools it 

 deposits crystals on the surface of the iron, 

 giving it a mottled appearance. Galvanized 

 iron is extensively used in corrugated and plain 

 sheets for cisterns, roofs and many buildings. 

 In parts of South Africa it is in such general 

 use for dwellings that whole villages and towns 

 are composed of houses made of this material, 

 lined with match boarding. In Western Can- 

 ada it is used for roofing, but it is unsuitable 

 there for any other part of houses, as it affords 

 little protection against cold. Ship's bolts, 

 nails, screws, wire netting, fencing and tele- 

 graph wires are among the articles usually 

 galvanized. During the South African War 

 large cylinders of galvanized iron filled with 

 earth and stone 

 were extensively 

 used for block- 

 houses and minor 

 fortifications. 



GALVANOM ' - 

 ETER, a deli- 

 cately-adjusted 

 instrument used 

 to detect and 

 measure the 

 strength of an 

 electric current. 

 It consists of a 

 coil of insulated 

 wire surrounding 



GALVANOMETER 



a magnetic needle, hung so that it is made to 

 move by the slightest electric current sent 



