631,835. Knitting-machines. MELLOR, BROMLEY, & CO., Ltd., and SHORTLAND, A. May 13, 1947, No. 12847. [Class 74 (ii)] [Also in Group XXII] The butts 2 of the jack sinkers of a straightbar machine are reinforced by an inverted T-shape plate 3 folded centrally around the rear edge of the sinker butts so that each butt is reinforced on both sides, and a strip of the plate extends along each side of the blade 1 of the sinker. A portion 3d of that part 3a of the plate reinforcing one side of the butt 2 may be folded round the front edge of the butt. Overlapping of the edges of the butts by the reinforcing plate prevents relative movement between the sinker and the plate if the rivets securing the plate to the sinker become loose. The portion of the plate on one side of the sinker may be indented as at 6 to register with a hole 7, 5 formed in the other side portion and in the sinker 1 and serves further to secure the plate to the sinker.