A eudiometer is a laboratory device that measures the change in volume of a gas mixture following a physical or chemical change.
Closed end of a eudiometer
Eudiometer after J.H. de Magellan, Teylers Museum
Joseph Priestley was an English chemist, natural philosopher, separatist theologian, grammarian, multi-subject educator, and liberal political theorist. He published over 150 works, and conducted experiments in several areas of science.
Portrait of Priestley, 1801
Priestley's birthplace (since demolished) in Fieldhead, Birstall, West Yorkshire – about six miles (10 km) southwest of Leeds
Mary Priestley, by Carl F. von Breda (1793); daughter of ironmaster Isaac Wilkinson, sister of industrialist John Wilkinson
A redacted version of A New Chart of History (1765); Priestley believed this chart would "impress" upon students "a just image of the rise, progress, extent, duration, and contemporary state of all the considerable empires that have ever existed in the world"