William Irvine, born near Enniskillen, Ireland, on the 3d of November, 1741, was educated at Trinity College, Dublin. Though preferring a military career, he adopted the medical profession to gratify the wishes of his parents. During the latter part of the Seven Years War between England and France, he served as surgeon on board a British man-of-war, and shortly before the restoration of peace, he resigned his commission, and coming to America in 1764, settled at Carlisle, Pennsylvania, where he soon acquired a great reputation and a large practice. Warm-hearted and impulsive, at the opening of the Revolution he adopted the cause of the colonists as his own, and after serving in the Pennsylvania Convention, he was commissioned in 1776 to raise a regiment in that State. At the head of these troops, he took part in the Canadian expedition of that year, and being taken prisoner, was detained for many months. He was captured a second time at the battle of Chestnut Hill, New Jersey, in December, 1777. On the 12th of May, 1779, Congress conferred on him the rank of brigadier-general. From 1782 until the close of the war, he commanded at Fort Pitt,--an important post defending the Western frontier, then threatened by British and Indians. In 1785, he was appointed an agent to examine the public lands, and to him was intrusted the administration of an act for distributing the donation lands that had been promised to the troops of the Commonwealth. Appreciating the advantage to Pennsylvania of having an outlet on Lake Erie, he suggested the purchase of that tract of land known as “the triangle.” From 1785 to 1795, he filled various civil and military offices of responsibility. Being sent to treat with those connected with the Whiskey Insurgents, and failing to quiet them by arguments, he was given command of the Pennsylvania Militia to carry out the vigorous measures afterward adopted to reduce them to order. In 1795, he settled in Philadelphia, held the position of intendant of military stores, and was president of the Pennsylvania Society of the Cincinnati until his death on the 9th of July, 1804. DANIEL MORGAN.