Title page of 'The Sceptical Chymist' by Robert Boyle, c 1661.
© Science Museum / Science & Society Picture Library
Boyle (1627-1691), seventh son of the first Earl of Cork, and his asistant Robert Hooke worked on improvements to the air pump invented by Otto von Guericke. Boyle's many experiments on air, vacuum, combustion, and respiration resulted the publication of 'The Sceptical Chymist', (London, 1661), a masterpiece of scientific literature in which he criticised confused theories then current, in particular those relating to alchemy. He claimed that there were more than the four Aristotelian elements - earth, water, air and fire - and that matter is composed of atoms and clusters of atoms in motion. In 1662 he formulated Boyle's Law, which states that the presure and volume of gas are inversely proportional. Boyle was one of the first chemists to prepare phosphorus.