Father of the modern science of artillery, born, the son of a Quaker, at Bath; established himself in London as a teacher of mathematics, as also his reputation by several mathematical treatises; turned his attention to the theoretical study of artillery and fortification; upheld Newton's principle of ultimate ratios against Berkeley, and in 1742 published his celebrated work, the "New Principles of Gunnery," which revolutionised the art of gunnery; was appointed engineer-in-general to the East India Company (1749), and planned the defences of Madras (1707-1751).