Farms and Estates were never large enough to warrant a full time skilled harness repair man. So this skill became a job where the harness maker would travel from farm to farm and would stay long enough to repair any leather work or harness that needed attention.
The tool above is a foot operated clamp or vise for holding the leather together while it was being stitched. First the leather to be sewn was punched with an awl. Then using two needles going in oposite directions the leather would be sewn with a waxed linen thread.
This service carried on until the horse on the farm lost favour to the tractor. This clamp is still used today in the workrooms of the Harness Shops or where leather work is repaired.