Compton, Alfred G. (Alfred George), 1835-1913 · New York : J. Wiley & Sons · leaf 124
110 FIRST LESSONS IN METAL- WORKING. tliumb and finger in grinding it, you turn tlie thumb a very little over toward the right, you will make a drill suitable for one kind of work, and if you turn it a little farther, one suitable for softer material. Your drill, when finished, will have, as you… … Fig. 60. The drill is now to be hardened and tempered. To harden it, hold the point in the flame, watch it till it reaches a cherry-red, and then plunge it into water. The butt of the drill wnll thus be left soft. Brighten the point, and hold it again in the flame, the point being this time just…
Metal-work
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