Circles, inscribed figures and incident rays on a ring
Equal portions cut from a circular annulus by intersecting incident rays
The sheet is filled with compass-drawn circles into which triangles and star-like figures are inscribed, several crossed by straight lines radiating from points on the circumference. A lower figure treats a circular ring or annulus, stating that all the portions made in it are similar and equal, that the outer angles are equal and less than right angles, and that the intersecting incident rays cutting the greater circumference divide the ring into two equal portions. The construction lines run through the circles to fix these intersections. The lower edge of the leaf is torn away, and further faint writing shows on the paper.
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Circles with inscribed triangles and radiating lines
Several circles carry inscribed triangles and star-shaped figures whose vertices are lettered, for example b d c, a, n e, q o p in one figure and f d, h, b, e c, g a in another. Straight lines run from points on the circumference across the interior. The figures set up the geometric relations elaborated in the note on the circular ring below.
Incident rays cutting equal portions from a ring
The lower figure with a circular ring states that all the portions made in the circular parallel are similar and equal among themselves, and that the outer angles are equal and less than right angles. The continuous succession of incident rays that intersect on the greater circumference of the ring cut from it two equal portions. The claim joins the geometry of the ring to the behaviour of the intersecting rays.