Mackey, John, so of Robert Mackey, a lieutenant in the provincial forces of 1747-8, as a native of Chester County and a representative farmer thereof.  He was a member of the Constitutional Convention of July 15, 1776; of the Council of Safety from Oct 17, 1777 to Dec. 4, 1777; of the Supreme Executive Council from Nov.. 21, 1777 to Oct 23, 1779; and in March, 1777, appointed a justice of the peace.  He resided in the twp of New London, SW of the village of that name, on a tract of land held under a Maryland patent.  He died in Sept. 1787, leaving a wife, Jane, and children - David, Robert, John, Margaret, Rachel )married to Wm. Sherer) and Mary (married to a Mr. Alison.)  His youngest son, John, inherited the land, about 240 acres.