Humphrey Ditton, an English mathematician, born in Salisbury, May 29, 1675, died Oct. 15, 1715. He studied theology, and was for some years a dissenting clergyman, but subsequently devoted himself to mathematics. He was encouraged by Sir Isaac Newton, through whose influence he was elected professor in the newly created mathematical school of Christ's hospital, a position which he retained till his death. In 1714 he published with Whiston an advertisement of a new method of finding the longitude at sea. The plan was approved by Newton, but rejected by the board of longitude; and it is said that the chagrin caused by this disappointment, and by some obscene verses of Swift, occasioned his death. He was the author of numerous mathematical treatises, among which are the following: "Of the Tangents of Curves;" "General Laws of Nature and of Motion;" "An Institution of Fluxions;" and " The New Law of Fluids, or a Discourse concerning the Ascent of Liquids in exact Geometrical Figures, between two nearly contiguous Surfaces."