Crookes, SIR WILLIAM, a great physicist and chemist, born in London in 1832, was a pupil and assistant of Hofmann at the Royal College of Chemistry, next superintended the meteorological department of the Radcliffe Observatory, and lectured on chemistry at the Science College,
Chester. In 1859 he founded the Chemical News, and in 1864 became also editor of the Quarterly Journal of Science. He was elected F.R.S. in 1863, vice-president of the Chemical Society in 1876, member of council of the Royal Society the year after, and in 1880 was awarded by the French Académie des Sciences an extraordinary prize of 3000 francs and a gold medal. He is an authority of the first rank on sanitary questions, especially the disposal of the sewage of towns, and his method of producing extreme vacua gave a great impulse to incandescent electric lighting. His original researches in chemistry and physics led to the discovery of the metal thallium in 1861, of the sodium amalgamation process for separating gold and silver from their ores in 1865, and of important discoveries in molecular physics and radiant matter, besides the invention of the Radiometer (q.v.). He is the author of Select Methods of Chemical Analysis (1871), and of works on beetroot sugar manufacture, dyeing, calico-printing, and sewage, and has translated books on chemistry and metallurgy. 'Crookes Tubes' are Vacuum Tubes (q.v.); and see RÖNTGEN, GAS. For Crookes's spiritualistic views, see SPIRITUALISM. Crookes was made a K.C.B. in 1897, and was President of the British Association in 1898.