Joseph Priestley

Joseph Priestley (1733-1804), a British chemist, isolated and described several gases, including oxygen, and is considered one of the founders of modern chemistry because of his contributions to experimentation.

Priestley was born on March 13, 1733, in Fieldhead, Yorkshire, the son of a Calvinist minister. He trained as a minister of the Dissenting church, which comprised various churches that had separated from the Church of England. He was educated at Daventry Academy, where he became interested in physical science. Later he became a tutor at Warrington Academy in Lancashire, where he was noted for his development of practical courses for students planning to enter industry and commerce.
Priestley was encouraged to conduct experiments in the new science of electricity by the American statesman and scientist Benjamin Franklin, whom he met in London in 1766. Priestley wrote The History of Electricity the following year. He also discovered that charcoal can conduct electricity. In 1767, Priestley became minister at Leeds, where he grew interested in research on gases. His innovative experimental work resulted in his election to the French Academy of Sciences in 1772, the same year in which he was employed by William Petty Fitzmaurice, 2nd Earl of Shelburne, as librarian and literary companion.
During Priestley's experiments in 1774, he discovered oxygen and described its role in combustion and in respiration. An advocate of the phlogiston theory, however, Priestley called the new gas dephlogisticated air and did not completely understand the future importance of his discovery.  Priestley also isolated and described the properties of several other gases, including ammonia, nitrous oxide, sulfur dioxide, and carbon monoxide. During his career, Priestley remained opposed to the revolutionary theories of the French chemist Antoine Lavoisier, who gave oxygen its name and correctly described its role in combustion.
In 1780, Priestley left his position with Petty because of religious differences. He became a minister in Birmingham. By this time he had turned to Unitarian thinking, and was considered a religious radical. His book, History of the Corruptions of Christianity (1782), was officially burned in 1785. Because of his open support of the French Revolution, a mob burned his house and effects in 1791. He went to live in London, and in 1794 he emigrated to the United States, where he pursued his writing for the remainder of his life. Priestley died in Northumberland, Pennsylvania, on February 6, 1804.

After his death, Dr. Thomas Cooper, a professor at Dickinson College, and friend of Priestly, purchased a collection of apparatuses from Priestly for the college.  Among the items purchased was the Burning Glass Priestley used to discover oxygen.  The College felt that such a purchase would add much to the its reputation.  Today, the Priestly collection is located in the Dickinson College Archives, Carlisle, Pennsylvania.

"Priestley, Joseph," Microsoft(R) Encarta(R) 97 Encyclopedia. (c) 1993-1996 Microsoft Corporation.