To remove the portion between the sawed lines take the chisel, [Fig. 56] (the same directions to be used for grinding and sharpening a chisel as are used for the plane-iron), pare lightly (about half through the width of the piece), cut down to the gauge line, and then turn the piece around and finish from the other side, leaving a straight surface at the bottom of the notch. Be careful not to take too heavy a cut, for the chisel will be hard to guide if the workman has to exert his whole strength to push it through the wood. The chisel has a tendency to go down into the work if the flat side is not used as a guiding surface; this side, if kept in contact with the solid wood, will insure a straight surface, and consequently accurate work.
Fig. 54.
Fig. 55.
Fig. 56.
The lining on the exercise is made with the gauge for the lines running parallel with the edge, with the square and the knife for the lines at right angles to the edge, and with the bevel, [Fig. 57], and the knife for the oblique lines. Figs. [58] and [59] give methods for finding the angle of 45 degrees, which is the angle that is used for the oblique lines.
Fig. 57.