Joseph Priestley pioneered research into the nature and composition of gases involved in physiological processes, including air inspired and expired during the respiratory cycle, and was the first scientist to report the discovery of oxygen.

Born into a poor family in a village near Yorkshire, England, Priestley lost his mother at an early age and was sent to live with his aunt, a devout Protestant. He was educated at religious schools that endorsed nonconformist beliefs; he never forma lly studied science, but he did excel as a scholar of languages, logic, and philosophy. Priestley became a country preacher, but eventually turned to teaching. While employed at the Warrington Academy in the 1760s, he argued that school curriculums should reflect contemporary discoveries, rather than following outdated classical models. In 1762, Priestley married Mary Wilkinson, the sister of one of his schoolmates.

In 1766 Priestley visited London, England, and met Benjamin Franklin...