(1) Drive piece of iron rod in eye to hold head by. Make full red hot, lay rod on edge of slack trough, harden the largest end, then turn small end in water, watch for temper in face, then the same to small end. When you have both ends right, keep turning them round in water until middle is about black - hot, then cool off. Do not dip deep. The colour will vary with different qualities of steel, and can only be determined by trial. With ordinary steel, from brown to blue will be about the thing. (2) A hammer weighing 1 lb. should be allowed 15 seconds to cool down before plunging, and then you will require nothing but clear water. Hammers weighing 2 lb., 3 lb., or 4 lb., should be allowed 30 seconds.