Cannon, John, a Reformed Presbyterian minister, was born at Dungiven, County Derry, Ireland, Nov. 19, 1784. In 1788 the family came to America, and settled in Pennsylvania. After studying some time in a private way, he entered Jefferson College (then at Cannonsburg, Pa.), where he graduated in 1810. In 1811 he commenced a private course in theology, and was licensed in 1815. In due time he accepted a call from a congregation in Greensburg (Pa.) and vicinity, and in 1816 was ordained and set apart as the minister of that, congregation. At a meeting of the Synod in 1821 he was appointed to visit the Church in South Carolina, to aid in settling certain difficulties which had arisen. He remained pastor at Greensburg until Feb. 2, 1835, when he died. See Sprague, Annals of the Amer. Pulpit, IX, v, 68.