t 3/8
in. as shown at Fig. 183; then turn the chisel to the position shown at
Fig. 184 and remove the small piece as shown. Continue these two
operations until you are about half-way through the wood and then start
in a similar manner at the line _a_, Fig. 183, after which turn the other
edge of the timber uppermost and repeat the methods shown.

[Illustration: Fig. 182.--Sawing away Waste Material.]

[Illustration: Fig. 183.--Using the Chisel and Mallet for Mortising.]

Fig. 185 shows the sketch of a mortise which has its side removed so as
to show the method of successive cuts with a chisel when removing the
core from a mortise; this, in conjunction with the other sketches,
clearly shows the methods of working. In many woodwork examinations the
examiners insist that the mortise shall be removed by successive cuts
with the chisel, but we certainly advise the removal of much of the waste
wood with a boring bit, provided the worker can keep straight and well
within the limitations of his gauge lines.

[Illustration: Fig. 184.--Removing Waste of Mortise with Chisel.]

REMOVING HAUNCHING.--After removing the mortise hole, the small portion
which is called the haunching will require to be removed with a chisel.
This calls for no special remark, as it is clearly shown in Figs. 187 and
188. Fig. 186 shows an everyday type of mortise and tenon joint
separated; it is used in cases where a straight joint is required on the
upper or lower edge of the work, whereas the upper rail of Fig. 176 shows
the full haunch on the top edge. In cases such as Figs 187 and 188, where
the edges of the frames are grooved to receive panels, etc., the width of
the tenon is reduced by the width of the groove.

[Illustration: Fig. 185.--Mortise with Side Removed.]

[Illustration: Fig. 186.--The Joint Separated.]

[Illustration: Fig. 187.--Removal of Haunching.]

[Illustration: Fig. 188.--Haunching with Groove above.]

This must be remembered by the worker when marking out his stiles with
the marking knife. Fig. 187 (right-hand sketch) shows the haunch, tenon,
and groove G at the bottom. Fig. 188 (left-hand illustration) shows G
(groove) at top, and HH (the haunch) at the bottom. Tenons may be glued
together and wedged as shown at Fig. 176 if for inside work; but if for
outside work they are generally smeared with thick paint and wedged up.
For light-class cabinet work it is usual to cut the mortise about
seven-eighths of the distance throug