, painted late in life by
Rembrandt Peale, after he had left off wearing his wig American-style (c. 1800)|alt=Half-length portrait of elderly man with wispy brown hair. He is wearing a black jacket and a white shirt.
Emigration to Northumberland The last three years the Priestleys spent in Britain were a time of political upheaval. During the
Birmingham Riots of 1791, which began on the second anniversary of the
storming of the Bastille in the wake of the conservative British reaction against the
French Revolution, the Priestleys' home, Joseph's church, and the homes of many other
religious Dissenters were burned. The Priestleys fled
Birmingham and attempted to live in
London, but could not escape the political turmoil. In 1794, they joined the tide of 10,000 emigrants who moved to America during the largest emigration from Europe to America until the end of the
Napoleonic Wars. The Priestleys left Britain at the beginning of April on the
Samson, and arrived in
New York City on June 4, 1794. Two of their three sons, Joseph, Jr. (eldest) and Harry (youngest), had already emigrated to the United States in August 1793, along with Joseph Priestley's friend, the radical activist
Thomas Cooper. Their middle son,
William, had moved to America from France, probably early in 1793, following the
September massacres of the previous year. Although Europeans knew Priestley best as a scientist (he had published his paper on the discovery
oxygen gas in 1774), Americans knew him best as a defender of religious freedom and as an advocate for
American independence. Immediately upon his arrival, he was
fêted by various political factions vying to gain his support. Priestley declined their entreaties, however, hoping to avoid the political discord that had embroiled him in Britain. He wrote to
John Adams that he "made it a rule to take no part whatever in the politics of a country in which I am a stranger, and in which I only wish to live undisturbed". (Priestley never became a citizen of the United States.) He also turned down an opportunity to teach chemistry at the
University of Pennsylvania at this time. On their way to Northumberland, the Priestleys stopped in
Philadelphia, where Joseph delivered a series of sermons that helped promote the spread of
Unitarianism. According to J. D. Bowers, who studied Priestley's influence on Unitarianism in America, "[f]or a decade Priestley served as the inspiration and leading force in the spread of Unitarianism in America and the formation of numerous societies that followed his teachings on congregational formation, the education of youth, lay preaching, and espousing one's faith in the presence of opposition from (and to) both the Protestant majority and a competing liberal faction." Through Priestley's influence, at least twelve congregations were founded in Maine, Massachusetts, New York, Vermont, Pennsylvania, Virginia, and Kentucky, including the
First Unitarian Church of Philadelphia and Northumberland's Unitarian Universalist Congregation of the Susquehanna Valley. When he preached, Unitarians and non-Unitarians flocked to hear him and his sermons were published throughout the country. (1793)|alt=Quarter-length portrait, showing a woman in a brown and gray lace bonnet with a bow and leaning on her right hand. While Priestley enjoyed preaching in Philadelphia, he could not afford the expense of living there; he also disliked the city's
Quakers, who he believed were too opulent, and feared the
yellow fever epidemic that had recently decimated the city. He considered settling in
Germantown, which had better access to transportation and communication than Northumberland, but his wife preferred the country and wanted to be near her sons. Priestly then debated about splitting his time between Northumberland and Philadelphia, but soon realized this plan was impractical. Determined to ensure the future economic stability of his family, he bought land and settled in Northumberland by July 1794, which was "five days of rough travel" north of Philadelphia. They both hoped that, in time, their new community would grow.
Settling in Priestley yearned for a more cosmopolitan community than Northumberland provided, writing to his sister that it was "seemingly almost out of the world" and complaining that he had to wait a week for news. He wrote to his friend
John Vaughan: "We know but little more than we did when we left you of European affairs." During the winter of 1794–1795, Priestley wrote to friends that his situation was very "distant from my original views" and "my time here is far from passing so agreeably as it did in England", yet he was "very thankful for such an asylum" and he attempted "to make the best of my situation". In his letters to friends back in Britain, Priestley consistently referred to himself as an exile and to England as his real home. His wife was happier with the couple's situation and wrote to William Vaughan: "I am happy and thankful to meet with so sweet a situation and so peaceful a retreat as the place I now write from. Dr. Priestley also likes it and of his own choice intends to settle here, which is more than I hoped for at the time we came up...This country is very delightful, the prospects of wood and water more beautiful than I have ever seen before and the people plain and decent in their manners." Priestley's son, Joseph Priestley Jr., was a leading member of a consortium that purchased of land along
Loyalsock Creek (between the North and
West Branches of the Susquehanna River). Shortly thereafter,
Thomas Cooper, a friend of Joseph Priestley's, published a pamphlet in Britain titled
Some Information Respecting America, meant to encourage others to settle in Pennsylvania and offering instructions on how to do so. It detailed a clear plan for establishing and financing a settlement. The French translation, ''Renseignemens sur l'Amérique'', was, according to one scholar, "carefully phrased in legal terminology" and "lucidly outline[d] an ambitious financial venture". However, it is unclear whether Cooper's scheme was related to the lands that the younger Priestleys had purchased. Apparently technically unrelated to either of these schemes, but influenced by Cooper's, poets
Samuel Taylor Coleridge and
William Wordsworth, full of idealism and angered at Priestley's treatment in
Birmingham, intended to emigrate to America and establish a
utopian community which they called "Pantisocracy" (derived from the Greek for "equal rule of all"). They assembled twelve couples who were interested not only in demanding physical labor but also in a life of the mind, but none of them had enough money to embark on the project, which required much capital. Therefore, the poets undertook a lecture tour of England to raise funds; however, they never generated enough money and never emigrated. The utopia was not built and few immigrants arrived in Northumberland as a result of Cooper's schemes. After the failure of Cooper's endeavor, Priestley attempted to convince other friends to move to Northumberland, particularly those he had made in America, but to no avail. Priestley wrote in his
Memoirs that "the settlement was given up, but being here, and my wife and myself liking the place, I have determined to take up my residence here, though subject to many disadvantages. Philadelphia was excessively expensive, and this a comparatively cheap place; and my sons, settling in the neighborhood, will be less exposed to temptation, and more likely to form habits of sobriety and industry." Priestley was eventually forced to defend himself in print. Family matters also made Priestley's time in America difficult. His youngest son Harry died on December 11, 1795, probably of
malaria. Mary Priestley died on September 17, 1796; she was already ill and never fully recovered after the shock of her son's death. On September 19 of that year Joseph wrote: "This day I bury my wife....she had taken much thought in planning the new house and now that it is far advanced and promises to be everything she wished, she is removed to another." After dinner on Monday 14 April 1800, various members of Priestley's household fell ill, with symptoms of food poisoning, which prompted the
Reading Advertiser to falsely accuse Priestley's son
William, of trying to poison them with arsenic. Priestley continued the educational projects that had been important to him throughout his life, helping to establish a "Northumberland Academy" and donating his library to the fledgling institution. He exchanged letters regarding the proper structure of a university with
Thomas Jefferson, who used the advice when founding the
University of Virginia. Jefferson and Priestley became close and when he had completed his
General History of the Christian Church, he dedicated it to President Jefferson, writing that "it is now only that I can say I see nothing to fear from the hand of power, the government under which I live being for the first time truly favourable to me." Of all of the religious works Priestley published in the United States, and there were many, it was his four-volume
General History that was the most important. Stretching from 475
CE to Priestley's present, he tracked and explained what he saw as the history of Christianity and its "corruptions", referencing his own
An History of the Corruptions of Christianity (1772–74). However, he ended it by praising American religious toleration. Priestley attempted to continue his scientific investigations in America with the support of the American Philosophical Association. However, he was hampered by lack of news from Europe; unaware of the latest scientific developments, Priestley was no longer on the forefront of discovery. Although the majority of his publications focused on defending the outmoded
phlogiston theory against the "
new chemistry", he also did some original work on
spontaneous generation and dreams. As Robert Schofield, Priestley's major modern biographer, explains: Priestley published more scientific items during his decade in the United States than during all his years in England: some 45 papers, not counting reprintings, and four pamphlets, not counting subsequent editions, but in general his science was now anticlimactic. Few of his papers contributed anything significantly new to the field of chemistry; most were committed to combatting the new chemistry. Despite Priestley's reduced scientific importance, he stimulated an interest in chemistry in America. By 1801, Priestley had become so ill that he could no longer write or experiment effectively. On February 3, 1804, Joseph started a last experiment in his lab but was too weak to continue it. He went to a bed in his library, where he died three days later. Priestley's epitaph reads: ==Architecture and landscaping==