Joseph Priestley is best remembered for his contribution to the chemistry of gases. His lasting reputation in science is founded upon his discovery of oxygen which he made in August 1774. But, during his lifetime, Priestley's considerable scientific reputation rested on his invention of soda water, his writings on electricity, and his discovery of several "airs" (gases), the most famous being what he, Priestley, dubbed "dephlogisticated air" (oxygen).

Priestley died in 1804. At the time, he had been made a member of every major scientific society in the Western world. Some of his colleagues because of his known accomplishments believed that he deserved to called "the father of modern chemistry".

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