Wheellock
A wheellock, wheel-lock, or wheel lock is a friction-wheel mechanism which creates a spark that causes a firearm to fire. It was the next major development in firearms technology after the matchlock and the first self-igniting firearm. Its name is from its rotating steel wheel to provide ignition. Developed in Europe around 1500, it was used alongside the matchlock and later the snaplock (1540s), the snaphance (1560s), and the flintlock (c. 1610s). Design The wheellock works by spinning a spring-loaded steel wheel against a piece of pyrite to generate intense sparks, which ignite gunpowder in a pan, which flashes through a small touchhole to ignite the main charge in the firearm's barrel. The pyrite is clamped in vise jaws on a spring-loaded arm (or 'dog'), which rests on the pan cover. When the trigger is pulled, the pan cover is opened, and the wheel is rotated, with the pyrite pressed into contact. A close modern analogy of the wheellock mechanism is the operation of a lighter, where a toothed steel wheel is spun in contact with a piece of sparking material to ignite the liquid or gaseous fuel. A wheellock firearm had the advantage that it can be instantly readied