US Patent No. 399,936, granted March 19, 1889 to Edward William Serrell Jr. of New York, for a machine that removes waste floss from silk cocoons before reeling. Plates held over a hot-water basin are moved back and forth, agitating the cocoons while the floss is pulled out, replacing the hand-cleaning (débavage) that required great skill and labor. The document has a drawing sheet (side section and plan view), the specification, and three claims. It also lists the foreign patents granted for the invention.