# James Gregory

**Name**: Gregory**Born**: 1638**Died**: 1675**Category**: Scientists and Inventors**Finest Moment**: Invention of the reflecting telescope, 1633

'Invented the means of looking deeper into space, and the mathematics to power it as well'

Born in November 1638, at Drumoak, Aberdeen, into the talented Gregory family, whose members included a host of doctors and physicians. The Gregory family, indeed, produced mathematicians or doctors for centuries, somewhat akin to Bach for musicians, and all descended from a Rev. John Gregory of Drumoak, the father of James.

James was educated at Marischal College, Aberdeen and Padua. He published the first proof of the fundamental theorem of calculus, while in 1663 he published Optica Promota (The Advance of Optics), in which he described the first practical reflecting telescope, now called the Gregorian Telescope. Additionally, as a throw-away idea, he introduced the estimation of stellar distances by photometric means.

At about 1665 he went to Padua to study mathematics, writing in 1667 Vera Circuli et Hyperbolae Quadratura (The True Squaring of the Circle and of the Hyperbola). In this work he showed the distinction between convergent and divergent series. He also wrote Geometriae Pars Universalis (The Universal Part of Geometry) in 1668, giving a series of rules for finding the areas of curves and the volumes of their solids of revolution.

James was Professor of Mathematics at St Andrews University (1669-74) and at Edinburgh University (1674-75). He is believed to have been a great influence on Isaac Newton, and was certainly the main link between Scotland and Newton's work, whose mathematics were thereby being taught in Scottish universities before it was in Oxford or Cambridge.

This advanced level of knowledge owes a debt, in no small part, to the unique atmosphere in Aberdeen, whose universities were more resistant to the theocratic pretensions of the Kirk than those further south, such as Glasgow, Edinburgh, & St Andrews. It was in those latter establishments that the Calvinists took hold.

James Gregory died tragically young, aged 37, and with less recognition than he deserved, in Edinburgh, in October 1675.