Patent for a new and improved nut-lock. This design "is to produce a nut-lock which will require a minimum number of parts to adjust, will require no other tools than a wrench, which will stay where adjusted in spite of any amount of pounding or concussion, and which, when desired, may be removed without difficulty. To this end [the] invention consists in a nut provided with a serrated face and a washer having sharp spring-lips engaging with the serrations. [The] invention also consists in a peculiarly-constructed washer for locking the nut" (lines 18-30).