A slingshot, shanghai, flip, bean shooter, Wrist-Rocket or catapult (primarily British English) is a small hand-powered projectile weapon. The classic form consists of a Y-shaped frame held in the off hand, with two rubber strips attached to the uprights. The other ends of the strips lead back to a pocket which holds the projectile. The pocket is grasped by the dominant hand and drawn back to the desired extent to provide power for the projectile (up to a full span of the arms with sufficiently long bands). Slingshots depend on strong elastic materials, typically vulcanized natural rubber or the equivalent, and thus date back no further than the invention of vulcanized rubber by Charles Goodyear in 1839 (patented in 1844). By 1860, this 'new engine' had already established a reputation for juvenile use in vandalism, as well as at least one human death.