Patent for a new and improved nut lock. This design "consists of a volute spring-washer which is formed of a stiff or steel strong plate that is coiled or set up in . . . an edgewise manner, and is provided with one or more projections or spurs on its top and bottom surfaces, adapted to engage with the under side of the nut and the fish-plate or other object, said spurs or projections being formed on the top and the bottom edges of the inner and outer coils of the spring-washer" (lines 20-29).