Wheatstone , Sir Charles

(1802–1875) British physicist

After a private education in his native city of Gloucester, Wheatstone began business in London as a musical-instrument maker (1823). His early scientific researches were in acoustics and optics and his contributions were numerous. Thus he devised a ‘kaleidophone’ to illustrate harmonic motions of different periods; he suggested a stereoscope (1838) that, using two pictures in dissimilar perspective, could give the appearance of solidity; he showed that every Chladni figure was the resultant of two or more sets of isochronous parallel vibrations; and he demonstrated how minute quantities of metals could be detected from the spectral lines produced by electric sparks.

Perhaps his most important work, however, was to produce, with William Cooke, the first practical electric telegraph system. In 1837, in conjunction with the new London and Birmingham Railway Company, Cooke and Wheatstone installed a demonstration line about one mile long. Improvements rapidly followed and, with the needs of the railroads providing the impetus and finance, by 1852 more than 4000 miles of telegraph lines were in operation throughout Britain. Wheatstone constructed the first printing telegraph (1841) and a single-needle telegraph (1845). He made contributions to the development of submarine telegraphy and to dynamos. The Wheatstone bridge, a device for comparing electrical resistances, was not invented by Wheatstone but brought to notice by him.

Wheatstone was appointed professor of experimental philosophy at King's College, London, in 1834 and was knighted in 1868. At his death he held about 40 awards and distinctions. He was prolific in his inventions and had an extraordinary ability to turn his theoretical knowledge to practical account.