George Sinclair (mathematician)

George Sinclair (Sinclar) (d. 1696) was a Scottish mathematician, engineer and demonologist. The first Professor of Mathematics, Glasgow, he is known for Satan's Invisible Works Discovered, (c. 1685), a work on witchcraft. He wrote in all three areas of his interests, including an account of the “Glenluce Devil”, a poltergeist case from c. 1654, in a 1680 book mainly on hydrostatics and dealing also with coal.

Life

He was probably from the East Lothian area. He became a professor of the University of Glasgow, April 18, 1654, initially in a philosophy chair, then in a chair founded for mathematics. In 1655 he made descents in a diving bell off the Isle of Mull, to look at the wreck of a ship from the Spanish Armada there.^[1]

He was deprived of his university post in 1666, as a Presbyterian.^[2] He then worked as a mineral surveyor and engineer, and was employed in particular by Sir James Hope. He was brought in by the magistrates of Edinburgh, about 1670, to oversee piping of water from Comiston into the city.^[3]

On 3 March 1691, Glasgow appointed him again to the professorship of mathematics, which had been vacant.

Controversy

James Gregory, then a professor at the University of St Andrews, attacked Sinclair in a 1672 pamphlet The New and Great Art of Weighing Vanity, under the name of Patrick Mather or Mathers, archbeadle of the University of St Andrews. Gregory was both a Cartesian and an Episcopalian, and self-consciously invoked the Hobbes-Wallis controversy in aiming at the non-conformist Sinclair.^[2] An appendix to the work, Tentamina de motu penduli et projectorum,^[4] was a more important essay on dynamics, regarded by D. T. Whiteside as a probable source of Isaac Newton’s theory of resisted motion.^[5] Sinclair wrote an answer to Gregory,^[6] but it remained unpublished.

In 1684 he published as his own a work Truth's Victory over Error. It was in fact an English translation by Sinclair of the Latin inaugural dissertation given by David Dickson, who became Professor of Divinity, Glasgow in 1640, on the occasion in 1650 when he moved to Edinburgh. This was pointed out in short order.^[7]

Notes