John Hadley (1731 – 5 November 1764) was an English chemist and physician. Born in London to Henry Hadley, he was educated at Queens' College, Cambridge, graduating B.A. in 1753. In 1756 he was appointed the fourth

Professor of Chemistry Chemistry is the scientific study of the properties and behavior of matter. It is a natural science that covers the elements that make up matter to the compounds made of atoms, molecules and ions: their composition, structure, properties, ...

at Cambridge University, the oldest continuously occupied chair of Chemistry in the UK. During his time there he co-operated in 1758 with

Benjamin Franklin Benjamin Franklin ( April 17, 1790) was an American polymath who was active as a writer, scientist, inventor, statesman, diplomat, printer, publisher, and political philosopher. Encyclopædia Britannica, Wood, 2021 Among the leading inte ...

on a series of experiments to investigate latent heat. They found that a mercury thermometer sprayed with ether which was then evaporated by blowing could fall to −7 degrees Celsius in a warm room. The Professorship was unpaid so Hadley studied medicine and obtained in 1758 a Physick Fellowship. He then moved to London in 1760 and got a post as Assistant Physician at St Thomas' Hospital. In 1763 he became full Physician to Charterhouse School and became a Fellow of the

Royal College of Physicians The Royal College of Physicians (RCP) is a British professional membership body dedicated to improving the practice of medicine, chiefly through the accreditation of physicians by examination. Founded by royal charter from King Henry VIII in 1 ...

. In 1758 he was elected as a

Fellow of the Royal Society Fellowship of the Royal Society (FRS, ForMemRS and HonFRS) is an award granted by the judges of the Royal Society of London to individuals who have made a "substantial contribution to the improvement of natural knowledge, including mathemat ...

. He died in 1764 of a fever at the age of 33.

References

* L.J.M.Coleby ''Annals of Science'', Vol VIII, pp 165–174 {{DEFAULTSORT:Hadley, John 1731 births 1764 deaths alumni of Queens' College, Cambridge Fellows of Queens' College, Cambridge Fellows of the Royal College of Physicians Fellows of the Royal Society Professors of chemistry (Cambridge, 1702) British chemists 18th-century English medical doctors