ClipArt ETC
It consists of a steam cylinder and piston and its rod, and to the rod is firmly secured a steel rock-drill. The cylinder is supported upon a heavy tripod that may stand in any position and present the point of the drill in any direction. The steam or compressed air is conveyed to the cylinder through a hose, and when ready for work it delivers its tremendous thundering blows upon the rock in rapid succession.

Pneumatic Rock Drill

It consists of a steam cylinder and piston and its rod, and to the rod is firmly secured a steel rock-drill.…