This Day in Science History - February 6 - Joseph Priestley

February 6^th marks the passing of Joseph Priestley. Priestley was an English theologian and natural philosopher who is best known with this experimental works with gases or "airs". He was the first to identify several gases including the element oxygen. This discovery helped answer the old question: Why do things burn? The prevailing theory of the time held there was a substance present in all things called phlogiston. Things would burn until they become saturated with phlogiston and any fire would go out. Priestley's found his new air greatly increased the process of burning and called it "dephlogisticated air" since it appeared to contain no phlogiston. Even though his discovery seemed to support the phlogiston theory, it was one of the key elements to launch Lavoisier's chemical reaction theories that started the Chemical revolution of the 19^th Century.

Priestley began his work with gases with a ready supply of phlogistated air, or carbon dioxide. He obtained near limitless supplies from a brewery near his ministry. One of the most notable achievements from this was a process to easily create carbonated water.