Abstract Through investigating the discovery process of carbon monoxide, it was clear that the discovery process was not only the discovery history of a chemical substance but also the history of rise and fall about phlogiston theory. British scientist Priestley who believed phlogiston theory first prepared and studied it in the laboratory and called it heavy inflammable air. British chemist William Cruickshank who believed oxidation theory proved that it was carbon monoxide by experiment. This made scientists mostly believed oxidation theory and leaded to the end of phlogiston theory. Through this history people realized that the innovative theoretical thinking had important implications for scientific research.
