US Patent No. 460,629, granted October 6, 1891 to Hilaire de Chardonnet of Besançon, France, for improvements in a machine that spins collodion (nitrated cellulose) into artificial silk filaments. Six sheets of drawings (Figs. 1-14) show the frame, spinning dies, nippers, bobbins and reeling mechanism, followed by a specification and 13 claims. The text describes the collodion solution, die and valve design, water-cooled coagulation, bobbin winding, and recovery of ether and alcohol solvents with potash and sulphuric acid. It builds on his earlier US patents on artificial silk.