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To describe ye Parabola (& other figures
after ye same manner) pretty exactly.
Figure 1

Thake a squire cbe , soe yt cb = r 2
(for then the [illeg] circle described by ( bc )
will bee as crooked as ye Parabola at
the vertex d ). Divide ye other leg ( be )
of ye Squire into any number of pts,
Then get a plate of Br [illeg] |a|sse &c: lkfd streight & eaven.
And taking one point d for ye vertex of it & another
point c for ye Squire to move [illeg] n soe yt cd = cb = r 2 , &
wearein [illeg] |g| away ye edge of the plate untill (ye [illeg] |S|quire
being erected) ab = qd . the squire touching ye plate at
a . thus shall ye edge adf become Parabolicall. wth ye
Rad: ab describe a circle adg & by that [meanes] it may
bee knowne when ab = a . \Instead of ye leg be a / Demonstraco
\circle may be used/ Supose aq = y . cd = cb = r 2 then [illeg] . Then is [illeg] r r 4 + [illeg] z z [illeg] cq [illeg] ad = x x + y y = ab . & ac = r r 4 + x x + y y .
[illeg] |A|nd cq = r r 4 + x x . & dq = x .
Demonstracon.
qd = x . cd = r 2 = cb . cq = r 2 x . aq = r x = y . ac 2 = r r 4 + x x
ab 2 = r r 4 + x x r r 4 & ab = x . Q.E.D.

Another description of ye Parabola y |w| e  [sic] ye
compasses. Make ab = bc = r 4 . Make ce = cd Figure 2
& ce bd . Make af = ae , & bf = bd
then shall f be a point in ye Parabola.

Another. [illeg] |M|ake ab = r + x 2 = ac . | eb = x ce |
& ye point c shall bee in ye parabola.
This like ye first by calculation may bee
made use of in other lines.