...arles P. Stone (who had been assigned to the command of a special corps of observation on the Tight flank of the Army of the Potomac), with a considerable body of troops, then had his Headquarters at Poolesville , a short distance from Conrad's and Edwards's Ferries, on the Potomac River. These ferries were not far from Leesburg, the capital of Loudon County, Virginia, where it was reported that the Confede...