g F F', and its
end B B. From centre C draw circle D, the upper half of which will serve
to represent the moulding. Mark on A the length or depth the cutting
edge requires to be, ascertaining the same from the construction shown
in Figure 292, and mark it as from C to K'. Then draw line E E, passing
through point K. Draw line G, standing at the same angle to A A as the
face _h b_, Figure 292, of the cutter does to the line A A, and draw
line H H, parallel to G. From any point on G, as at I, with radius J,
draw a quarter of a circle, as K. Mark off this quarter circle into
equal points of division, as by 1, 2, 3, etc., and from these points of
division draw lines, as _a_, _b_, _c_, etc.; and from these lines draw
horizontal lines _d_, _e_, _f_, etc. Now divide the lower half of circle
D into twice as many equal divisions as quarter circle K is divided
into, and from these points of division draw perpendiculars _g_, _h_,
_i_, etc. And where these perpendiculars cross the horizontal lines, as
_d_, will be points through which the curve may be drawn, three of such
points being marked by dots at _p_, _q_, _r_. If the student will, after
having drawn the curve by this construction, draw it by the construction
that was explained in connection with Figure 79, he will find the two
methods give so nearly identical curves, that the latter and more simple
method may be used without sensible error.

[Illustration: Fig. 293.]

[Illustration: Fig. 294.]

When the curves of the moulding are not arcs of circles they may be
marked as follows:

Take the drawing of the moulding and divide each member or step of it by
equidistant lines, as _a_, _b_, _c_, _d_, _e_, _f_, _g_, in Figure 294;
above the moulding draw lines representing the cutter, and having found
the depth of cutting edge for each member by the construction shown in
Figure 292, finding a separate line, _a b_, for each member of the
moulding, transfer the depths so found to the face of the cutter; divide
the depth of each member of the cutter into as many equal divisions as
the corresponding member of the moulding is divided into, as by lines
_h_, _i_, _j_, _k_, _l_, _m_, _n_. Then draw vertical lines, as _o_,
_p_, _q_, _r_, etc.; and where these lines meet the respective lines
_h_, _i_, _j_, etc., are points in the curve, such points being marked
on the cutter by dots.

CHAPTER XIII.

_EXAMPLES IN LINE-SHADING AND DRAWINGS FOR LINE-SHADED ENGRAVINGS._

Although