Doubling frame to spin sewing cotton from two yarns, unknown maker, 1858.

This is a machine for doubling cotton yarn to form thread for sewing or other purposes. It is similar to a throstle spinning frame, but is without drawing rollers, and is arranged for spinning two yarns into one thread. The cops containing the yarn are placed in the creel along the centre of the frame, and the yarn for each spindle is led down underneath a glass rod in a trough of water, and between a pair of brass rollers, to a fier fixed at the top of the vertical spindle. From the fier it passes to a bobbin loose upon the spindle, and as the flier rotates it twists the two yarns together, and at the same time winds them on to the bobbin. As the rollers do not feed out the yarn as fast as the flier would wind it on a fixed bobbin, the difference is made up by the bobbin slipping round under the pull of the yarn. The bobbins rest upon a rail which is raised and lowered by heart cams placed below the machine, so winding the thread uniformly on the whole length of each bobbin. A feature of this machine is the extent to which frictional driving is employed. From the main central shaft two parallel shafts are driven by leather-covered pulleys, and each of these shafts has on it 24 metal discs or friction cones, each driving a leather-covered conical pulley, formed on the base of a flier spindle, no cords or belts being used. The rollers are, however, connected by positive gearing with the driving shaft.