Channel and Break is one technique used to create a hole, a hollow or a bas relief in stone. Drill a series of holes outlining the area to be removed using a pneumatic carving tool with a carver's drill (use your free hand to rotate the drill) or a rotary impact hammer. Mark your drill bit with tape for the depth required. The hole diameter should be slightly more than the channeling tool thickness; the width between holes should be slightly less than the channeling tool width. Now use the channeling tool to remove the "web" remaining between the holes. When the area has been channeled, use a hand point or a pneumatic tool with a 4-point chisel to break or remove the interior.