Sheraton, Thomas; Bensley, Thomas; Mathews, James; Bensley, Thomas [Oth.]; Mathews, James [Oth.]; Terry, George [Oth.]; Jordan, Jeremiah Samuel [Oth.]; Wayland, L. [Oth.]: The Cabinet-Maker And Upholsterer's Drawing-Book: In Three Parts (London: Printed For The Author, By T. Bensley; And Sold By J. Mathews ... C. Terry ... J.S. Jordan ... L. Wayland ... And By The Author, 1793)

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line 7.7, confequently it will turn twenty-eight times on a line
twice its length.
Of the Line of Polygons * on tbe Sector,
This line is intended to divide a circle into equal parts, by
which any kind of Polygons, from a pentagon to a duodecagon,
may be formed. Hence it is diftinguifhed by the letters POL
on this inftrument.
Let it be required to divide the circle, Fig. 8, into five,
which forms a Pentagon. Take the radius or half diameter
of Fig. 8, and opening the fedlor, as deferibed by Fig. 7, place
the compafs on the point 6.6, marked radius. In this polition
keep the fedtor, and, without any variation of the inftrument,
you may divide the circle 8 from 4 to 12. In the cafe before us
it is into five; therefore take the compares from the points 6,
and extend them till they touch 5.5, and this opening will go
five times on the circle 8, as'will be evident if you take 5.5 in
your compaffes from Fig. 7, and apply it to Fig. 8.
>
Laftly, if you want the circle 8 divided into twelve, by
which to form a Duodecagon (fee Plate II. Fig. 26), the fecior
Hill remaining unaltered, place your compafs legs on the points
* “ Polygon, from polus, many, and gonia, a corner, having many cornel's
or angles.”
12.12,