asts.

114. _Sill._--In carpentry the base piece, or pieces, A, on which the
posts of a structure are set.

115. _Skew-Back._--The course of masonry, such as a stone, A, with an
inclined face, which forms the abutment for the voussoirs, B, or
wedge-shaped stones comprising the arch.

116. _Spandrel._--The irregular, triangular space, A, between the curve
of an arch and the enclosing right angle.

117. _Strut._--In general, any piece of a frame, such as a timber A, or
a brace B, which resists pressure or thrust in the direction of its
length.

[Illustration: _Fig. 118.-Fig. 123._]

118. _Stud, Studding._--The vertical timber or scantling, A, which is
one of the small uprights of a building to which the boarding or
plastering lath are nailed.

119. _Stile._--The main uprights of a door, as A, A; B, B, B, rails; C,
C, mullions; D, D, panels.

_Tie Beam._--See _Queen Post_.

120. _Trammel._--A very useful tool for drawing ellipses. It comprises a
cross, A, with grooves and a bar, B, with pins, C, attached to sliding
blocks in the grooves, and a pen or stylus, D, at the projecting end of
the bar to scribe the ellipse.

121. _Turret._--A little tower, frequently only an ornamental structure
at one of the angles of a larger structure.

122. _Transom._--A horizontal cross-bar, A, above a door or window or
between a door and a window above it. Transom is the horizontal member,
and if there is a vertical, like the dotted line B, it is called a
_Mullion_. See _Stile_.

123. _Valley Roof._--A place of meeting of two slopes of a roof which
have their sides running in different directions and formed on the plan
of a re-entrant angle.

CHAPTER VIII

DRAWING AND ITS UTILITY

A knowledge of drawing, at least so far as the fundamentals are
concerned, is of great service to the beginner. All work, after being
conceived in the brain, should be transferred to paper. A habit of this
kind becomes a pleasure, and, if carried out persistently, will prove a
source of profit. The boy with a bow pen can easily draw circles, and
with a drawing or ruling pen he can make straight lines.

REPRESENTING OBJECTS.--But let him try to represent some object, and the
pens become useless. There is a vast difference in the use of drawing
tools and free-hand drawing. While the boy who is able to execute
free-hand sketches may become the better artist, still that art would
not be of much service to him as a carpenter. First, because