Joseph Priestley, FRS (13 March 1733 (O.S.) – 6 February 1804) was an 18th-century English theologian, Dissenting clergyman, natural philosopher, chemist, educator, and political theorist who published over 150 works. In “Experiments and Observations on Different Kinds of Air,” he reviews experiments with gases. A common theme in this work is measuring the volumes of gases held in glass tubes, and their increase or decrease when exposed to other substances. He also tests the effects of gases on mice, plants and insects...