as a Zippo lighter. Pyrite held against a rotating steel wheel produced a spark directed at the priming charge in the flash pan. The wheel is rotated by a spring under tension. It would be wound up like a clock before each firing, held by a latch and fired by a lever that released the latch. To avert stalling, the pyrite would be lowered onto the rotating wheel rather than being permanently held against it. The mechanism would also remove a cover from the flash pan at the moment of firing, sliding it forward. The cover would retain the priming charge in the flash pan during transit. The mechanism was altogether quite complicated. Consequently it was expensive and found limited use. The next advance in firearm design was the snaplock, which used flint striking steel to generate the spark. The flint is held in a rotating, spring-loaded arm called the cock. This is held cocked by a latch and released by a lever or trigger. The steel is curved and hinged. This accommodates the arc of the flint, maintaining contact with the steel. The spark produced is directed downward into the flash pan. The snaphance incorporates a mechanism to slide the pan cover forward at the moment of firing. The doglock incorporates a second latch (or dog) as a safety mechanism that engages the cock in a halfway or half-cock position. The dog is independent of the trigger. The dog is only released when the lock is bought to the full-cock position. The miquelet lock is the penultimate of the flint-sparking locks. It has an "L" shaped frizzen, the base of which, covers the flash pan and is hinged forward of the pan. The flint strikes against the upright of the "L" and flips the frizzen forward to reveal the pan to the sparks created. The miquelet lock also has a half-cock mechanism similar in function but differing in operation from the doglock. The flintlock is also referred to as the true flintlock to distinguish it from other flint-sparking mechanisms. It is also known as the French lock. It uses a frizzen similar to the miquelet lock and has a half-cock position. The distinction between the two locks is that the flintlock uses a single vertical sear to latch the cock in both the cocked and half-cocked positions. The sear is a lever that pivots in the vertical plane perpendicular