Show hamm rs r y air pneumatic hammers driven by compressed air are now generally used ired instead ot of hand labor tor for chipping and cleaning iron and steel castings and billets so BO as to free them from any defects which would injure the finished forms into which they are to tee be rolled or drawn this thin hammer will dothe work of three men the same principle has been applied in the shipyard hl tor for calking la in which the tool can be b worked very fast doing the work of five or six men |