Priestley, Joseph (1733-1804). was born at Fieldhead, Yorkshire. He was Nonconformist minister at Needham JIarket, Nantwich, Leeds, and Birmingham, and was also for some time classical tutor at Warrington Nonconformist Academy. While here he was created LL.D. of Edinburgh, and in 17GG, in consequence of his electrical researches, was elected to the Royal Society of London. Next year he published his History of Electricity. He attracted the attention of Lord Shelburne, but, after the appearance of his Disquisitions on Matter, he lost the position of librarian and literary companion. In 1791 he was obliged to leave Birmingham after his chapel had been destroyed by a mob who disapproved of his sympathies with the French Revolution; and, after living three years at Hackney, he became an American citizen. Priestley's chief claim to remembrance is his discovery of oxygen, which he called "dephlogisticated air."