US Patent No. 2,331, granted November 10, 1841 to J. B. Tillinghast of Norwalk, Ohio, for a method of constructing and arranging cocooneries for silk-worms. It describes a 140-foot cocoon room with feeding frames suspended from the rafters, where worms are moved after the fourth moulting and fed and allowed to spin cocoons on whole trees or large branches. The text gives dimensions, ventilation shutters, protection against mice, and the patent claim; page 1 carries the patent drawing (Fig. 1).