VIFar down in the ground, underneath the Ross-Bankside No. 1, a great block of steel was turning round and round. The under surface of it had blunt steel teeth, like a nutmeg-grater; on top of it rested a couple of thousand feet of steel tubing, the “drill-stem,” a weight of twenty tons pressing it down; so, as it turned, it ate into the solid rock, grinding it to powder. It worked in the midst of a river of thin mud, which was driven down through the center of the hollow tubing, and came up again between the outside of the tubing and the earth. The river of mud served three purposes: it kept the bit and the drill-stem from heating; it carried away the ground-up rock; and as it came up on the outside of the drill-stem, it was pressed against the walls of the hole, and made a plaster to kee
