US patent specification, granted July 17, 1835, to Oliver C. Burr, a machinist of Millbury, Worcester County, Massachusetts, for an improvement to looms. The device regulates the cloth beam so that it winds up a small amount of cloth with each pick of filling, keeping the cloth a uniform thickness. The scan has a photolithographed drawing page and handwritten specification text that lists the lettered parts (levers, springs, catch wheel, cog wheel) and explains how the mechanism operates.