Used with
permission of Maiken Naylor, University at Buffalo, Buffalo, NY, USA,
http://ublib.buffalo.edu/libraries/units/sel/exhibits/stamps
Joseph Priestly (1733-1804) was a great experimental chemist, but in his own mind more importantly a minister, theologian, and educator. He was persecuted for his political and religious views to the point that he had to leave England and emigrate to the United States, where he spent the last ten years of his life. His important work with gases included the preparation of oxygen, the discovery of ammonia, sulfur dioxide, carbon monoxide, nitric oxide, and hydrogen sulfide.