Patent for a new and improved nut-lock. This design "consist[s] of a strip of metal having the looped portion adapted to embrace the bolt, and having the downwardly-bent spring portion or end forming a biting-edge, the rearwardly-extending straight portion bent upward . . . to form a bearing point or edge, which is also adapted, in conjunction with the edge to grip the fish-plate . . . the forwardly-extending straight spring portion overlapping the straight portion, the inner curved edge of which lies in the path of the edge of the nut when the latter is turned upon the bolt" (lines 76-89).