Crookes, Sir William, 1832-1919. Knight. Chemist.

William Crookes was born the son of Joseph Crookes, tailor, and Mary Scott in London, in 1832. His education was irregular but eventually he attended A W Hofmann's Royal College of Chemistry in London in 1848. In 1850 he became Hofmann's assistant until 1854. He attended lectures at the Royal Institution of Great Britain (RI) given by Michael Faraday (1791-1867). In 1854 he was Superintendent of the Meteorological Department of the Radcliffe Astronomical Observatory in Oxford. In 1854 he worked with John Spiller on the collodion process of photography and improved it. In 1855 he taught chemistry at the College of Science in Chester. In 1856, he researched into photography and compiled a Handbook to the Waxed-Paper Process in Photography (Chapman and Hall, 1857). He also undertook the editorship of the Liverpool Photographic Journal in 1856, and in 1857 he became Secretary of the London Photographic Society, a position he held until 1858. He was also the editor and proprietor of the weekly Chemical News journal from 1859. In 1856 he married Ellen Humphrey and they subsequently had ten children. Crookes researched into spectra and in 1861 he discovered a new element which he called thallium. In 1863 he was elected Fellow of the Royal Society (RS). In 1865 he discovered the process of extracting precious metals from ores, however it had already been discovered in America and Crookes had to negotiate half rights over patents for using sodium amalgam, only to be superseded by the discovery of potassium cyanide as the best solvent of gold. From 1867 he became interested in spiritualism, which affected his views on science. By 1870 he decided to investigate spiritualism as a scientist and prove the existence of psychic force, an investigation which caused him to lose some respect as a scientist. Despite this, he developed the technique of determining the atomic weight of thallium. In 1873 he wrote the paper `Attraction and Repulsion resulting from Radiation' published in Philosophical Transactions of the Royal Society; this resulted in his invention of the radiometer in 1875. In 1876 he researched into radiant matter and found that molecular pressure was the result of radiant matter being affected by magnets. In the 1880s he worked on incandescent lamps for electricity. He became Director of the Electric Light and Power Company in 1881 and patented his designs on incandescent lamps, however he sold these as newer and better designs developed. In c1891 he became Director and later Chairman of the Notting Hill Electric Light Company which prospered in its time. In 1890 he was elected President of the Institution of Electrical Engineers. In 1897 he was elected President of the Society for Psychical Research and in the same year he was knighted. He gave lectures on making diamonds at the RI in 1897 and became its Honorary Secretary in 1900 a position he held until 1912. In 1908 he was elected Foreign Secretary of the RS until 1913 when he was elected President of the RS, a position he held until 1915. He published papers in journals such as Philosophical Transactions of the Royal Society, as well as Proceedings of the Royal Society and in Chemical News. He died in 1919.