Hi
My gggrandmother is a Horne from Cockenzie (Janet Horne). I have spent years researching the Prestonpans and Cockenzie families. In the 1600’s and 1700’s there were migrations from Leith and Musselburgh to Prestonpans and Cockenzie. Given that all four were main fishing ports, this makes sense. Your John Horne looks to be born 24/05/1764 in Leith to a Peter Horne and Jean Shaw. Also your John Horne 1821 married my