482 THE COLLIERY GUARDIAN. September 6, 1918. SUPREME! HARDY “SIMPLEX” Type B5. Extra light, for ripping & brushing. HARDY “SIMPLEX” Type B7 Heavy, for sinking. HARDY “SIMPLEX” Type B6. Medium, for drifting, etc. These machines are in use to the number of many thousands all over the world. They have utterly defeated all competition, and stand supreme as examples of fast-boring rock drills of immense durability and superb engineering finish. TRIALS ARRANGED. I