Benjamin Hartford and William B. Tilton of Enfield, New Hampshire
Hartford and Tilton improved upon the construction of heddles (the mechanisms that raise and lower warp threads) by using strips of rolled flat metal with an eye punched through the middle of each strip to allow for the passage of warp yarns. Heddles were commonly constructed of cord. The replacement of metal for cord produced a more durable heddle. These one-piece metallic strips and the construction of the heddle frame were the basis of their patent. The heddles slid on two rods and were attached to adjustable clasps, permitting the heddles to correspond to the part of the reed (a comb-like device used to space the warp yarns evenly) that was in operation.