In 1848, with Pratt & Company continuing in its old line, a new firm, Pratt & Letchworth, was organized to manufacture saddlery hardware, carriages, malleable iron, and steel castings. Manufacturing was initially conducted at 165 Main Street, with inmates of the nearby jail contracted for the work. The principals of the partnership were the Pratt brothers and William P. Letchworth from Auburn, where the latter owner had used convict labor in a like enterprise. By 1872 the firm was the largest manufacturer of saddlery hardware in the United States. Mr. Pratt remained associated with the firm as senior partner until 1896, when it was organized as a stock company, the Pratt and Letchworth Co. The company diversified by adding cast iron toy production in 1889, following the hiring of George S. Crosby, toy designer for Welker & Crosby Company, of Brooklyn. The following year, in 1890, Pratt and Letchworth acquired the patent rights and inventory of another toy manufacturer, F. W. Carpenter Company of Harrison, New York. Pratt & Letchworth marketed their toys as Buffalo Toys and as Buffalo Indestructible Malleable Iron & Steel Toys. Their trade mark was of a charging buffalo. Their works are regarded as some of the finest cast iron toys produced.