Joseph Priestley

Joseph Priestley FRS (/ˈpriːstli/; 24 March 1733 – 6 February 1804) was an English chemist, Unitarian, natural philosopher, separatist theologian, grammarian, multi-subject educator and classical liberal political theorist. He published over 150 works, and conducted experiments in several areas of science.

Priestley is credited with his independent discovery of oxygen by the thermal decomposition of mercuric oxide, having isolated it in 1774. During his lifetime, Priestley's considerable scientific reputation rested on his invention of carbonated water, his writings on electricity, and his discovery of several "airs" (gases), the most famous being what Priestley dubbed "dephlogisticated air" (oxygen). Priestley's determination to defend phlogiston theory and to reject what would become the chemical revolution eventually left him isolated within the scientific community.

Priestley's science was integral to his theology, and he consistently tried to fuse Enlightenment rationalism with Christian theism. In his metaphysical texts, Priestley attempted to combine theism, materialism, and determinism, a project that has been called "audacious and original". He believed that a proper understanding of the natural world would promote human progress and eventually bring about the Christian millennium. Priestley, who strongly believed in the free and open exchange of ideas, advocated toleration and equal rights for religious Dissenters, which also led him to help found Unitarianism in England.

A scholar and teacher throughout his life, Priestley made significant contributions to pedagogy, including the publication of a seminal work on English grammar and books on history; he prepared some of the most influential early timelines. The educational writings were among Priestley's most popular works. Arguably his metaphysical works, however, had the most lasting influence, as now considered primary sources for utilitarianism by philosophers such as Jeremy Bentham, John Stuart Mill, and Herbert Spencer. Priestley is especially famous for his Essay on the First Principles of Government (1768), an early work of modern liberal political theory.

Early life and education (1733–1755)

Joseph Priestley was born in Birstall near Batley in the West Riding of Yorkshire. He was part of an English Dissenting family that did not follow the Church of England. As a child, he was very smart and could remember lots of things. He learned many languages and subjects, including Greek, Latin, Hebrew, French, Italian, German, Aramaic, and Arabic.

Later, he went to a school called Daventry Academy in Northamptonshire, where he studied even more. There, he read important books that helped him think differently about religion and the world. He decided he wanted to spend his life learning and teaching others.

Needham Market and Nantwich (1755–1761)

In 1755, Joseph Priestley began working in a small town called Needham Market in Suffolk. He wanted a busy city life with lots of discussions, but the town was quiet and the people there liked things just the way they were. When they learned about his different ideas, fewer people came to his services, and he lost support from his aunt. He tried to start a school but local families were not interested.

Luckily, in 1758, Priestley moved to Nantwich, Cheshire, where he was much happier. The people there were more open to his ideas. He started a school where he taught science and bought instruments for his students. He even wrote his own book about English grammar, called The Rudiments of English Grammar, because he thought the books at the time were not very good. His school did well, and in 1761, he was offered a teaching job at Warrington Academy.

Warrington Academy (1761–1767)

In 1761, Joseph Priestley moved to Warrington to teach languages and rhetoric at a school for people who did not follow the Church of England. He enjoyed his time there and made many friends, including a doctor named John Aikin, his sister Anna Laetitia Aikin, and a famous potter named Josiah Wedgwood. In 1762, Priestley married Mary Wilkinson, and they had a daughter named Sarah in 1763.

Priestley loved teaching and writing about history. He believed learning history was very important for young people because it helped them understand how the world worked and how people had improved over time. He also invented carbonated water in 1767 by finding a way to add carbon dioxide gas to water.

Leeds (1767–1773)

Joseph Priestley moved to Leeds in 1767, where he became the minister of Mill Hill Chapel. During his time there, he had two sons, Joseph Junior and William. Priestley was an active writer and thinker, creating many works on religion and science. He believed in educating young people to strengthen his community and wrote about his ideas in a series of books called Institutes of Natural and Revealed Religion. These books shared his views on religion, which were different from many others at the time.

Priestley also studied science, especially electricity and chemistry. He wrote a book about electricity and discovered how to make carbonated water, which he thought might help prevent a sickness called scurvy. Though he did not become rich from this discovery, others did. Priestley’s work earned him recognition from the Royal Society, who gave him an award for his scientific contributions.

Calne (1773–1780)

In 1773, Joseph Priestley and his family moved to Calne in Wiltshire, England. There, Priestley worked as a librarian and tutor for Lord Shelburne, which gave him time to pursue his interests in science and philosophy. During this period, he became an adviser to Shelburne on political matters.

Priestley wrote many important philosophical books during his time in Calne. He believed in ideas like determinism and materialism, meaning he thought everything in the universe was made of matter and followed natural laws. He also wrote about his scientific experiments, especially his work on different kinds of air. His most famous discovery was oxygen, which he isolated in 1774 by heating mercuric oxide. Priestley called this new air "dephlogisticated air" and described its properties in detail in his book Experiments and Observations on Different Kinds of Air. His work helped advance the study of chemistry and our understanding of gases.

Birmingham (1780–1791)

In 1780, Joseph Priestley and his family moved to Birmingham, where they lived happily for ten years. In 1791, however, violent mobs attacked people who did not share the same religious beliefs as most of the town. This event became known as the Priestley Riots. Because of the violence, Priestley had to leave Birmingham and could not return to his home or laboratory.

During his time in Birmingham, Priestley became part of a group called the Lunar Society. This was a club of inventors, scientists, and thinkers who met to share ideas. Priestley made many friends there, including James Watt, the inventor of improvements to the steam engine. He also continued his experiments and wrote many important scientific papers. One of his most famous works was about a gas he discovered, which we now call oxygen. Priestley believed in an old scientific idea called the "phlogiston theory," even though another scientist named Antoine Lavoisier had new ideas that later became the foundation of modern chemistry. Priestley never accepted Lavoisier's theories, preferring to stick with what he believed was right based on his own experiments.

Hackney (1791–1794)

After the riots in Birmingham, Joseph Priestley and his wife moved to Lower Clapton, a district in Middlesex. There, he gave lectures on history and natural philosophy at the Dissenting academy, at the New College at Hackney. Friends helped them rebuild their lives by giving money, books, and lab equipment.

Priestley’s sermons during this time showed his belief that the end of the world was near. He saw the French Revolution as a sign of big changes to come. Life became harder for Priestley, as some people made mean drawings and letters about him. He considered moving to France but decided against it because of the growing tension between England and France. Eventually, Priestley and his wife left England and moved to America in 1794.

Pennsylvania (1794–1804)

See also: Joseph Priestley House

Joseph Priestley moved to America in 1794, arriving in New York City. He later settled in Northumberland County, Pennsylvania, where he helped start the First Unitarian Church of Philadelphia and turned down a teaching job at the University of Pennsylvania.

In America, Priestley stayed busy writing about politics and science. He defended his beliefs and exchanged ideas with important figures like Thomas Jefferson, who later used Priestley's advice when creating the University of Virginia. Though Priestley’s health declined, he kept encouraging interest in science in America until his death in 1804.

Degrees

Joseph Priestley was a learned man who earned the title LL.D. He studied at the University of Edinburgh and served as a preacher and librarian for the Earl of Shelburne from 1773 to 1780. He was a pastor for a Unitarian congregation in Birmingham from 1780 to 1791, and later worked at the Gravel Pit meeting house in Hackney, London, until 1794. He then lived in Northumberland, Pennsylvania, from 1794 until his passing in 1804.

Priestley made many important discoveries in science. In 1772, he discovered nitric oxide. In 1774, he discovered oxygen, hydrochloric acid, and ammonia. In 1775, he found sulphur dioxide and silicon tetrafluoride. He was a member of the Royal Society and the American Philosophical Society. He was born on 24 March 1733 in Fieldhead, near Leeds, Yorkshire, England, and died on 6 February 1804 in Northumberland, Pennsylvania.

Legacy

Joseph Priestley was highly respected during his lifetime and after. By the time he died in 1804, he was a member of major scientific societies around the world. Priestley published more than 150 works on many subjects, including science, politics, and religion. His ideas influenced many famous thinkers and helped shape modern chemistry.

Towns where Priestley lived honor him with statues and plaques. Schools and buildings are named after him, and awards are given in his name for scientific achievements. Priestley’s discovery of oxygen is celebrated as an important milestone in chemistry.

Archives

The papers of Joseph Priestley are kept at the Cadbury Research Library at the University of Birmingham. These papers help us learn more about his life and work.

Selected works

Main article: List of works by Joseph Priestley

Joseph Priestley wrote many important books on science, history, and religion. Some of his well-known works include The Rudiments of English Grammar from 1761, The History and Present State of Electricity from 1767, and Experiments and Observations on Different Kinds of Air from 1774–77, where he shared his discoveries about air and oxygen. His writings also covered topics like government, history, and religion, showing his wide range of interests and ideas.