Experiments and Observations on Different Kinds of Air

By the late eighteenth century, scientists had discovered certain types of gas, such as 'fixed air' (carbon dioxide), but their composition was little understood. Relatively few investigations into gases had taken place, and so the polymath Joseph Priestley (1733–1804) was able to make major breakthroughs in the field using a range of experimental techniques. While living near a brewery, he found that it was possible to outline the shape of the gas above fermenting beer with smoke, and that...