Robert Hoore, an English mathematician, born at Freshwater, Isle of Wight, July 18, 1635, died at Gresham college, London, March 3, 1703. His father, a clergyman, destined him for the church; but his health being too feeble for study, he devoted his leisure to invention. In 1655 he was appointed assistant in chemistry to Dr. Thomas Willis at Oxford, and in 1664 he became professor of geometry in Gresham college, and first Cutlerian professor of mechanics in the royal society. In 1666, having produced a model for the rebuilding of London after the great fire, he was appointed city surveyor; but his plan was not carried into execution. In 1677 he succeeded Oldenburg as secretary of the royal society. In 1691 he was made a doctor of physic by a warrant from Archbishop Tillotson. He made a practical improvement in the pendulum attached to clocks, causing it to swing in small arcs by the application of the recoil escapement. (See Clocks and Watches, vol. iv., p. 698.) He also applied himself to devise means to regulate watches, and when Huygens had some watches constructed, the balances of which were regulated by a spiral spring, Hooke accused Oldenburg, secretary to the royal society, of having communicated to strangers discoveries deposited in the society registers.

But that the application is due to Huygens, is not only apparent from a perusal of the latter's description in his Machinoe qaoedam et Mechanicam published in 1675, but is proved by other evidence. On the publication of Newton's Prin-cipia, he also claimed the previous discovery of the principle of gravitation. He was jealous of all other inventors, and was involved in continual disputes concerning different inventions, generally pretending that they were all taken from ideas of his own. He left numerous works, among which is his "Micrographia, or Physiological Descriptions of Minute Bodies made by Magnifying Glasses" (London, 1665). His "Posthumous Works, containing his Cutlerian Lectures and other Philosophical Discourses," was published in London in 1705.