Phlogiston theory

Phlogiston theory is a 17th century hypothesis regarding combustion. The theory was invented by [J. J. Becher]? late in the 17th century and extended and popularized by [Georg Ernst Stahl]?, who declared the rusting of metal to be a combustion process. Phlogiston theory states that in all flammable materials contain phlogiston, a substance without color, odor, taste, or weight that is liberated in burning. "Phlogisticated" substances are those that contain phlogiston and are "dephlogisticated" when burned. The ash of the burned material is supposed to be the true material. The theory received strong and wide support throughout a large part of the 18th century until it was proved wrong by the work of Antoine Laurent Lavoisier, who revealed that combustion requires oxygen. [Joseph Priestley]?, however, defended phlogiston theory throughout his lifetime. [Henry Cavendish]? remained doubtful, but most other chemists of the period, including [C. L. Berthollet]?, rejected it.