Gilbert, William

Gilbert, William (1544-1603), English physicist and doctor, known primarily for his original experiments into the nature of electricity and magnetism. He was born in Colchester, Essex, and educated at St John's College, University of Cambridge. He began to practise medicine in London in 1573, and in 1601 was appointed physician to Elizabeth I.

Gilbert found that many substances had the power to attract light objects when rubbed, and he applied the term electric to the force these substances exert after being rubbed. He was the first to use the terms electric force, electric attraction, and magnetic pole. Perhaps Gilbert's most important contribution was the experimental demonstration of the magnetic nature of the Earth. The unit of magnetomotive force in the cgs system, the gilbert, was named after him. He was also the first exponent in England of the Copernican system of celestial mechanics, and he conjectured that fixed stars were not all at the same distance from the Earth. His most important work was De Magnete (1600; Of Magnets, Magnetic Bodies, and the Great Magnet of the Earth, 1890), probably the first great scientific work written in England.