Jackhammer

A jackhammer is a pneumatic or electro-mechanical tool that combines a hammer with a chisel, driving an internal piston up and down to repeatedly strike the chisel and break up rock, pavement and concrete. Samuel Miller patented the first steam-powered rock drill in 1806, Jonathan J. Couch built Americas first percussion drill around 1848 and patented it in 1849, and Joseph W. Fowle developed the first true compressed-air pneumatic drill around 1850 and 1851; William McReavy is credited with inventing the jackhammer itself and sold the patent to Charles Brady King. Demand for pneumatic drills grew rapidly with large mining and tunnelling projects, including the Mont Cenis tunnel between Italy and France, and the tool remains a standard piece of construction and demolition equipment.