About Joseph Priestley

Image courtesy of the
Archives and Special Collections,
Dickinson College, Carlisle, PA.

Joseph Priestley is best remembered for his pioneering work in chemistry and in particular for the discovery of oxygen. But he was also a prolific theologian, an innovative educator, and a liberal political philosopher.

Northumberland, Pennsylvania, his American home from 1794 until his death in 1804, encompassed about 100 houses when Priestley, age 61, emigrated from England, seeking haven from political and religious persecution.

Priestley was born of a cloth dresser in Fieldhead, an English village near Leeds, on March 13, 1733. From an early age the studious young man had aspired to the ministry. In 1752, he entered Daventry Academy where he began the religious journey that led him eventually to Unitarianism, which he was to endow with formative ideas. Priestley was foremost a Christian minister, and over half his published writing is devoted to theological discourse.

In 1755, he began his ministry at a small church at Needham Market, and in 1761 began teaching at Warrington Academy, the leading institute for Dissenters and nonconformists to the Church of England. In 1762, he married Mary Wilkinson, his wife for 34 years.

Engraving depicting Priestley's pneumatic chemistry apparatus from his book Experiments and Observations on Different Kinds of Air

Priestley, little taught in science, began in his early thirties to teach himself. By 1767, he had found a way to produce carbonated water, published The History and Present State of Electricity, and was named a Fellow of the Royal Society. By 1772, Priestley published another significant and widely read work - The History and Present State of Discoveries Relating to Optics, Vision and Colours. In 1773, he became librarian to the Earl of Shelburne, and with the leisure this afforded he made his most notable contributions to science, isolating eight gases � oxygen in 1774 � and describing the basic process of photosynthesis.

Priestley's mind could never be confined. Discrimination against Dissenters drew his attention to politics and confirmed him as an exponent of liberty. His support for the American Revolution and for British reform and his continued criticism of the Anglican Church alienated many. Finally, his defense of the French Revolution, beginning in 1789, exposed him to the harsh retorts of the popular press. In 1791, Birmingham's anti-French rioters destroyed Priestley's house, laboratory and library. Escaping to London, he and his wife departed in 1794 for America, where they would be reunited with their three sons, who had emigrated in 1793. The Priestley's daughter, Sarah, who was married, remained in England. Priestley's destination was a proposed colony for English Dissenters to be settled near Northumberland. Though the colony did not become a reality, Priestley built a fine manor house in the village.

In his last 10 years, Priestley identified carbon monoxide as a distinct "air" and published more than 30 scientific papers. He also wrote more that a dozen religious works, including his six-volume History of the Christian Church. He conducted Sunday services in his home and gave impetus to the Unitarian Church in Philadelphia. Joseph Priestley died February 6, 1804, at his home. He is buried in Northumberland's Riverview cemetery along with other members of the family.

About Joseph Priestley

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