‘Revolution: how oxygen changed the world’ charts the discovery of oxygen. Antoine Lavoisier found that water and air were not actually elements, and in the process discovered oxygen, hydrogen, and nitrogen. Lavoisier's work ushered in an age of ‘pneumatick chemistry’ — the study of gases. This new science was still prejudiced by classical ideas. For instance, contemporary thinkers thought that a substance called phlogiston existed, and was the essence of flammability. Lavoisier determined that burning did not release phlogiston into the air, but actually removed oxygen. One could think that atmospheric oxygen exists to give us life, but it was in fact life that gave the world oxygen, through biological processes.