1659-1708

English mathematician and astronomer who was one of the first to lecture publicly on Newtonian science. Gregory defended Isaac Newton's views in his Elements of Astronomy (1702); however, he disagreed with Newton's position on chromatic aberration, suggesting it might be eliminated by combing two lenses such that one reversed the effects of the other. This was accomplished by Chester Moor Hall (1733), who failed to publicize his work, and then again by John Dollond (1758).