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3 6 INTERNATIONAL EXHIBITION, ^76. completed the stitch. The tension device was composed of a grooved metal disk, attached to the overhanging arm by a screw, which served as its axis. The thread was wound once around the tension-wheel, and the wheel, grooved on its inner side to receive the wedge-shaped end of a vibrating clutch-bar, was moved at each stitch the distance necessary to deliver enough thread for a stitch. The long bight of thread necessary to pass about the bobbin was kept under the cloth to be operated upon by the hook, and was not drawn backwards and forwards through the needle-eye, as usual in this class of machines, the friction upon the thread consequently being greatly diminished. The presser-foot, placed in position by thick or thin material, was caused to act upon the tension-wheel actuating-clutch, to vary the length of thread delivered for fabrics of different thickness. The Wilcox & Gibbs Sewing-Machine Co., New York, N. Y This company exhibited their new machine with automatic tension, adapted to operate, without change, on the finest and coarsest threads with which this machine is ever used in family sewing. The rotating shaft had, attached at its forward end, a small hook that engaged the loop of needle-thread, and held it spread open until the needle in its next descent entered the loop held by the hook, which entered the new and discharged the old loop. The construction of this hook required great inventive skill and many special machines and tools to give it its exact and necessary shape. The stitch is known as the single thread or chain-stitch. The needle-bar actuating lever derived its movement from an eccentric on the hub of the fly-wheel. The stitch-regulator, that determined the extent of reciprocation of the four-motioned feeding device, was provided about its periphery with figures arranged to be shown through a slot in the cloth-plate, such figures indicating the number of stitches to the inch, with the stitch- regulator in that position. The spool of thread was supported upon an inclined spool-spindle, the head of the spool resting against a con caved disk, about which the thread was drawn without rotating the spool. The thread from the spool passed through an eye in the vibrating lever, and was so acted upon by pins between the lever and overhanging arm as to draw off at each stitch the amount of thread needed for the next stitch. When the thread was drawn or pulled for this purpose, it was held nipped between the faces of the automatic tension device, and could be drawn only from the spool. The thread, after leaving the vibrating arm, passed to the tension device. An eye at the upper end of the needle-bar, and a rest located near it, controlled the slack of the thread when the needle descended, and