Dr Priestley (1733-1804) was a nonconformist minister and scientist, who took up the study of chemistry. He was a pioneer in the chemistry of gases, and one of the discoverers of oxygen. He published a history of electricity, and was elected a Fellow of the Royal Society in 1766. Priestley aroused controversy with his various publications on religious matters, and was condemned as an atheist. As a consequence of his support for the French Revolution, his house in Birmingham was burned down by a mob in July 1791, destroying his library, papers and scientific apparatus. Not long afterwards he emigrated to America.The partnership of Josiah Wedgwood I (1730-95) and Thomas Bentley (1730-80) manufactured a series of large-scale portrait plaques of eminent men. They included renowned scientists, doctors and statesmen of the time. The series were produced in pairs, and Priestley's pair was the great mathematician Sir Isaac Newton (1642-1727). Wedgwood and Priestley probably first met in the 1760s through Wedgwood's partner Thomas Bentley. Wedgwood contributed towards Priestley's experimental work and in the 1780s supplied him with laboratory equipment in his new composition.