Rock Drill

The rock drill ilustrated differes from most other rock drills in that it really bores, and does not merely peck its way into the rock. The hollow drill stem, furnished with three or four splayed out teeth, is driven by means of hih pressure water. The drill is pressed against the face of the rock by a hydraulic ram with a force of 10 tons. To sink a hole 39 inches deep takes from 12 to 15 minutes. - There is a border around the image. Image size is correct. Many sizes available.