To make a circle about any assigned cinkeangle of equall
sides, and equall corners.
Drawe .ij. lines within the cinkeangle, from .ij. corners to the
middle on tbe .ij. contrary sides (as the last conclusion
teacheth) and the pointe of their crossyng shall be the centre
of the circle that I seke for. Then sette I one foote of the
compas in that centre, and the other foote I extend to one of
the angles of the cinkangle, and so draw I a circle about the
cinkangle assigned.
_Example._
A.B.C.D.E, is the cinkangle assigned, about which I would make a
circle. Therfore I drawe firste of all two lynes (as you see)
one from E. to G, and the other from C. to F, and because thei do
meete in H, I saye that H. is the centre of the circle that I
woulde haue, wherfore I sette one foote of the compasse in H.
and extende the other to one corner (whiche happeneth fyrste,
for all are like distaunte from H.) and so make I a circle
aboute the cinkeangle assigned.
[Illustration]
An other waye also.
Another waye maye I do it, thus presupposing any three corners
of the cinkangle to be three prickes appointed, vnto whiche I
shoulde finde the centre, and then drawinge a circle touchinge
them all thre, accordinge to the doctrine of the seuentene, one
and twenty, and two and twenty conclusions. And when I haue
founde the centre, then doo I drawe the circle as the same
conclusions do teache, and this forty conclusion also.