the tenon. After cutting the mortise and tenon, bore and chisel out
the hole for the wedge, taking care to cut the side toward the end on
a bevel to fit the wedge.

_No. 40. A tusk tenon or shoulder tenon_, Fig. 267, is one in which
the tenon proper is quite thin but is reinforced by a thicker shoulder
called a "tusk." The upper shoulder is beveled. The object of this
form is to weaken the mortised member as little as possible but at the
same time to increase the strength of the tenon. It is used in joining
tail beams to headers in floor framing.

_No. 41. A double mortise-and-tenon_, Fig. 267, consists of two tenons
side by side in one piece fitting into two corresponding mortises. It
is used in joinery, as in door-frames, but not in carpentry.

_No. 42. A haunched mortise-and-tenon_, Fig. 267, is made by cutting
away part of the tenon so that that part of it will be much shorter
than the rest. The haunch gives the tenon great lateral strength
and saves cutting so large a mortise hole. It is used in panel
construction, as where the rails are joined to the stiles of doors.

First plow the groove in all the members. This should be of the same
width as the thickness of the tenons, which is ordinarily one-third of
the thickness of the frame. The groove is approximately as deep as
it is wide. Lay out and cut the tenon the width of the entire piece,
minus, of course, the depth of the groove. The mortise should not come
too near the end, or the portion of wood outside it will shear out.
Hence the tenon is narrowed on the outside enough to insure strength
in the mortised piece. The rule is that the tenon should be one-half
the width of the rail, minus the groove. But enough of the tenon is
left full width to fill up the groove at the outer end of the mortised
piece. This is called the _haunch_. The width of the mortise is equal
to the width of the groove, its length to the width of the tenon.
Before assembling the panel frame, put soap or tallow on the corners
of the panel to prevent its being glued to the frame.

_No. 43. Table or taper haunching_, Fig. 267. Sometimes, as in table
construction, for the sake of stiffening the rail, or in places where
it is desirable that the haunch does not show, the haunch is beveled
from the tenon to the edge of the rail.

_No. 44. A bare-faced tenon_, Fig. 267, is one in which a cheek is
cut from only one side. It is used where the rail is thinner than the
stile and it is desirable to