Robert Boyle, Irish physicist and chemist, c 1670s.
© Science Museum / Science & Society Picture Library
Engraving by Vertue after Kerseboom. Boyle (1627-1691) was the seventh son of the first Earl of Cork. He 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 in 1661 of 'The Sceptical Chymist', in which he criticised current theories of matter, in particular those relating to alchemy. In 1662 he formulated Boyle's Law, which states that the presure and volume of gas are inversely proportional. He was a founder member of the Royal Society, but refused to become their first president as he was unwilling to take the oath of allegiance to the monarchy.