ordyng to the conclusion.
An other waie.
Another waie also maie you drawe a cinkeangle aboute a circle,
drawyng first a cinkeangle in the circle (whiche is an easie
thyng to doe, by the doctrine of the .xxxvij. conclusion) and
then drawing .v. touche lines whiche shall be iuste paralleles
to the .v. sides of the cinkeangle in the circle, forseeyng that
one of them do not crosse ouerthwarte an other and then haue you
done. The exaumple of this (because it is easie) I leaue to your
owne exercise.
THE XL. CONCLVSION.
To make a circle in any appointed cinkeangle of equall sides
and equall corners.
Drawe a plumbe line from any one corner of the cinkeangle, vnto
the middle of the side that lieth iuste against that angle. And
do likewaies in drawyng an other line from some other corner, to
the middle of the side that lieth against that corner also. And
those two lines wyll meete in crosse in the pricke of their
crossyng, shall you iudge the centre of the circle to be.
Therfore set one foote of the compas in that pricke, and extend
the other to the end of the line that toucheth the middle of one
side, whiche you liste, and so drawe a circle. And it shall be
iustly made in the cinkeangle, according to the conclusion.
_Example._
The cinkeangle assigned is A.B.C.D.E, in whiche I muste make a
circle, wherefore I draw a right line from the one angle (as
from B,) to the middle of the contrary side (whiche is E. D,)
and that middle pricke is F. Then lykewaies from an other corner
(as from E) I drawe a right line to the middle of the side that
lieth against it (whiche is B.C.) and that pricke is G. Nowe
because that these two lines do crosse in H, I saie that H. is
the centre of the circle, whiche I would make. Therfore I set
one foote of the compasse in H, and extend the other foote vnto
G, or F. (whiche are the endes of the lynes that lighte in the
middle of the side of that cinkeangle) and so make I the circle
in the cinkangle, right as the conclusion meaneth.
[Illustration]
THE XLI. CONCLVSION
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 angle
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