\fdO'^ - Old Forge Coal Mines

SURVEYING. 235
with radii equal to A B, describe arcs intersecting at D.
Join A D and B D. The triangle A B D is equilateral;
hence, each of its angles, as A, contains 60°. From Z> as a
Fig. 59.
center, with a radius A D, describe the arc A B.
A C xs tangent to this arc at the point A.
The line
(621) A B in Fig.
point, C D = C E.
From D and E as cen-
60 is the given line,
\Q
C the given
ters with the same .F^
radii, describe arcs in-
tersecting
2X F.
Through F draw C G.
Lay oK C G and C B
equal to each other,
and from B and G as
centers with equal
radii describe arcs intersecting at H.
angle B CH=^b°.
Draw C H. The