Gregory , family , scientists x Gregorie , family Gregory , David , 1661-1708 , astronomer x Gregorie , David Gregory , James , 1638-1675 , mathematician x Gregorie , James Gregory , David , 1627-1720 , inventor Gregory , Charles , son of David Gregory (1627-1720)

Gregory , family , scientists x Gregorie , family Gregory , David , 1661-1708 , astronomer x Gregorie , David Gregory , James , 1638-1675 , mathematician x Gregorie , James Gregory , David , 1627-1720 , inventor Gregory , Charles , son of David Gregory (1627-1720)

David Gregory of Kinnairdie (1627-1720), inventor, apprenticed by his father to a mercantile house in Holland. Returned in 1655, and succeeded to the estate of Kinnairdie on the death of an older brother. Highly regarded in medicine, having a large gratuitous practice both among the poor, and people of standing. First man in Aberdeenshire to possess a barometer, and his weather forecasts exposed him to suspicions of witchcraft. Moved to Aberdeen and investigated artillery. With help of an Aberdeen watchmaker constructed an improved model of a cannon, forwarding it to his eldest son David , and to Newton, who held it was 'for the diabolical purpose of increasing carnage', and who urged him to break it up.

David Gregorie (1661-1708, FRS 1692), astronomer, son of David Gregory (1627-1720). Professor of Mathematics at Edinburgh University in 1683, first professor to lecture publicly on Newtonian philosophy, enthusiastic promoter of Newton's 'Principia'. In 1691 went to Oxford where introduced to Newton, who became an intimate friend and who with Flamsteed influenced his appointment as Savilian Professor of Astronomy in Oxford. His principal work 'Astronomiae Physicae et Geometricae Elementa' in 1702 was the first text book composed on gravitational principles and remodelling astronomy in conformity with physical theory. Approved by Newton, who had included in it his lunar theory, and for which he wrote a preface. Gregory was a skilful mathematician who left manuscript treatises on fluxions, trigonometry, mechanics and hydrostatics, and who was also known for his printing in 1703 of all the writings attributed, with any show of authority, to Euclid.

James Gregory (1638-1675, FRS 1668) mathematician and elder brother of David Gregory (1627-1708) His scientific talent was discovered and encouraged by his brother, and in 1673 at age 24 he published his 'Optica Promota' containing the first feasible description of a reflecting telescope, his invention of it dating from 1661, and inspiring Newton to make his own reflecting telescope. Studied mathematics in Padua 1664-1667, publishing 'Vera Circuli et Hyperbolae Quadratura' in 1667, showing how to find the areas of the circle, elipse, and hyoerbole by means of converging series, and applying the same new method to calculation of logarithms. Friendly debate with Newton 1672-1673 as to merits of their respective telescopes. From 1674 first exclusively mathematical professor at Edinburgh.

Charles Gregory was one of the 32 children of David Gregory (1627-1720) and brother of the second David Gregory (1661-1708).