51�Թ�

Chisels.—The principal kinds of chisels are the paring chisel which is used entirely by hand, and the firmer chisel which is used with the mallet.

Edge tools are the firmer chisel, the mortise chisel, the socket chisel, the gouge, the hatchet, the adze, the drawing knife.

A and B are both oblique firmer chisels, A being ground with a bevel on one side only, and B with a bevel on each side.

A paring chisel worn to half its original length will serve for a firmer chisel, because when so worn it is long enough for the duty.

A chisel should not, however, be used alternately as a paring and a firmer chisel, because the paring chisel requires to be kept in much better condition than the firmer chisel does.