STANHOPE, CHARLES, Earl Stanhope, born in 1753, was the eldest son of Philip, the second earl, a man equally remarkable for his mathematical talents, and his liberal political opinions. The subject of this notice succeeded to the peerage in 1786, and died in 1816. By his first marriage he became the brother-in-law of Pitt; and on the mother's side he was closely allied to the Scottish earls of Haddington. This eccentric but public-spirited and most inventive man, while he divided his attention among a variety of inquiries, sufficient to have prevented excellence in any, had the rare merit of excelling in several most important pursuits, while in more than one he has bequeathed to the world discoveries that have proved most extensively useful. In politics he was a decided Whig, an assertor of religious toleration, and of non-intervention in the internal affairs of foreign states. Sometimes, however, he carried out the principles of his party with a boldness which other minds scrupled to follow; and in the latter years of his parliamentary life, Earl Stanhope used to be called "the minority of one." His political works were a refutation of Price's scheme of the sinking fund, an answer to one of Burke's invectives on the French Revolution, and an essay on juries. But his inventions in mechanical science are those by which he has secured the gratitude of posterity. They are too many to be here so much as completely enumerated. The principal of them, the Stanhope press, has been described in our article PRINTING, where notice has also been taken of his exertions for improving the process of stereotype. He was an early student of Franklin's theory of electricity, to which he contributed several valuable observations. Another of his most useful inventions was one for improving the locks of canals; and more curious ones were his two calculating machines, one of which performed addition and subtraction, the other multiplication and division.