Sir William Crookes

Crookes, Sir William (1832–1919), British scientist and inventor. He is credited with the discovery of the element thallium and experimented with an electronic vacuum tube. The Crookes tube, developed in the 1870s, was the forerunner of the modern cathode ray picture tube used in television sets. He also founded and edited Chemical News (1859), a scientific journal.

See also: Thallium.