PRIESTLEY ( )

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1 Laval University From the SelectedWorks of Fathi Habashi May, 2018 PRIESTLEY ( ) Fathi Habashi Available at:

2 PRIESTLEY ( ) Joseph Priestley ( ) (Figure 1) was born near Leeds in England. As a young man he studied Latin, Greek, and Hebrew then in he studied divinity. He later spent his time in preaching and teaching. He was a Dissenter, i.e., a Protestant who did not adhere to the Church of England. He wrote The Rudiments of English Grammar in 1761 which brought him the degree of Doctor of Laws from the University of Edinburgh in Figure 1 - Joseph Priestley He met Benjamin Franklin who was visiting England and who encouraged him to write the History of Electricity. The 700-page book became a reference to researchers for over a century. He ascertained experimentally several facts which were disputed and led to his membership in the Royal Society in In 1767 Leeds ( ) Priestley moved to Leeds in 1767 to take charge of a chapel which was the most dissenting congregation in England. Beside his religious works he devoted time to chemical experiments and commenced his investigations on airs. He lived next door to a brewery. He noticed that the air that covered the fermentation vats could extinguish flames and kill mice. This caught his attention, because about 20 years earlier, the Scottish physician Joseph Black had shown that if chalk is heated became lighter and gave off a gas that could extinguish flames and kill mice. Priestley took the air over the fermentation vats and dissolved it into water to give a sour mixture. He then did the same thing with the air that he got from chalk, getting the same sour mixture. This was an evidence that the gas from the chalk was the same as the gas from the fermentation vat. That is how he invented soda water and wrote a pamphlet with Directions for Impregnating Water with Fixed Air (1772). Fixed Air was a term given by Black for the gas that came out of solid limestone on heating. Calne ( ) In 1773 Priestly accepted an appointment by Lord Shelburne 1 ( ) in Calne near Bristol to direct the education of his children, to become his librarian, and to act as his general assistant. He had much leisure for scientific research. It was there that he made his discovery of oxygen and established its properties. He obtained the air by focusing the sun s rays on a sample of calx of mercury. He showed it decomposed to give dephlogisticated air, as the terminology that was used at the time. He first tested it on mice, who surprised him by surviving quite a while entrapped with the air, and then on himself, writing that it was "five or six times better than common air for the purpose of respiration, inflammation. He wrote Experiments and Observations on Different Kinds of Air ( ) in six volumes. The gas produced had the power of supporting combustion better and animal life longer than the same volume of common air. In 1774 he went on a tour of Europe with Lord Shelburne and while in Paris he 1 Became Home Secretary in 1782 and Prime Minister during the final months of the American War of Independence. The outbreak of the American War of Independence took place in 1775.

3 visited Lavoisier and showed him the method of procuring oxygen. Few years later the relation with Lord Shelburne ruptured and Priestley moved to Birmingham. Birmingham ( ) In 1780 Priestley moved to Birmingham to accept a ministerial position to preach on Sundays only so that he can devote more time to his researches. At Birmingham three volumes of his previous experiments on air were printed and he also contributed various papers to the Transactions of the Royal Society. He attempted to refute Lavoisier s attack on the phlogiston theory. He entered upon a new field of chemistry. The first of his discoveries was nitrous gas which may be said to have led to the knowledge of the constitution of the atmosphere. Priestley first made known sulfurous acid, fluosilicic acid, and muriatic acid, and pointed out easy methods of procuring them. He described with exactness the properties of each. He likewise pointed out the existence of carburetted hydrogen gas, discovered protoxide of nitrogen, and found out that an acid is formed when the electric sparks were made to pass for some time through an air. Riots in Birmingham While in Birmingham he was drawn into conflict with the established clergy. Kings, senators, and nobles, are the servants of the public and when they abuse power, the people have the right of deposing and of punishing them. Dissenters such as Priestley who supported the French Revolution came under increasing suspicion since relations between Britain and France were tense. William Pitt's administration argued that they wanted to overthrow the government. On July 14, 1791 on the second anniversary of the storming of the Bastille while Priestley and his friends were celebrating there was a riot that lasted three days believed to be initiated by the conservative administration of Prime Minister William Pitt the Younger. The rioters' main targets were religious Dissenters, most notably the politically and theologically controversial Joseph Priestley. Priestley s house was burned, his library, manuscripts, and apparatus were destroyed (Figure 2). Figure 2 - A painting of Birmingham riots and destruction of Priestley s house July 14, 1791

4 The riots aftermath In France, a decree issued on August 26, 1792 by the National Assembly conferred French citizenship on Joseph Priestley and others who had served the cause of liberty by their writings. Priestley accepted French citizenship, considering it a great honour. The relations between England and France worsened and this was followed by the declaration of war on February Priestley then escaped to London stayed there for two years then sailed in April, 1794 to America. William Pitt's administration began arresting radicals resulting in the Treason Trials in December In 1795 the American Revolution took place. In 1798 Benjamin Thompson ( ), later known as Count Rumford, left America to Britain where he established chemical research. In America Priestley arrived in New York in June 1794 and proceeded to Philadelphia then to Northumberland where his sons had settled. The Americans knew him best as a defender of religious freedom and as an advocate for American independence. 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. President Jefferson and Priestley became close. Priestley stimulated an interest in chemistry in America. His laboratory was probably the first scientifically-equipped laboratory in the United States and his library, which contained about 1600 volume, was one of the largest in America at the time. Museum On July 31, 1874, American chemists met at the Priestley house to celebrate the centennial of chemistry and to mark the 100 th anniversary of Priestley's discovery of oxygen. The meeting is recognized as the first National Chemistry Congress, and this led to formation of the American Chemical Society two years later on April 6, George Gilbert Pond ( ), Chemistry Professor from what is now Pennsylvania State University raised sufficient funds to buy the house which was in private hands after the death of Priestley, and attempted to make it a museum. However, he died before he could complete the project. On January 12, 1965, the Priestley House was designated a National Historic Landmark and in October 1970 the museum was opened to the public (Figures 3-5). It has been a frequent place of celebration for the American Chemical Society. A number of items that belonged to the Priestley family during their live in Britain and America are on display including the balance scales and microscope, portraits, prints, maps, charts, and books. Figure 3 - Priestley house

5 Figure 4 - Priestley s house became a National Historic Chemical Landmark, 1994 Figure 5 - Inside Priestley s house Legacy In 1974 the Priestley Medal (Figure 6) was awarded by the American Chemical Society. In October 1976, the ACS celebrated its own centennial in Northumberland. On April 13, 1983, ACS President spoke at the house to celebrate Priestley's 250 th birthday and the United States Postal Service issued a commemorative stamp (Figure 7).

6 Figure 6 - Priestley medal Figure 7 - Priestley commemorative stamp in 1983 Souvenir plaques are mounted in Calne (Figure 8) and Birmingham (Figure 9). Statues of Priestley are found in Leeds (Figure 10), in Bristol (Figure 11), and in Birmingham (Figure 12). The places where Priestley worked in England are shown in the map (Figure 13). Figure 8 - Plaque in Calne commemorating the discovery of oxygen by Priestley Figure 9 - Plaque at Birmingham Civic Society Figure 10 - Priestley in Leeds Figure 11 - Priestley in Bristol Figure 12 - Priestley in Birmingham

7 Figure 13 - Map of England showing Leeds in the north and Birmingham in the middle. Calne is in the region Bristol - Bath - Stonehenge