Studies in the quadrature of the circle and lunes
Quadrature diagrams, interlace rosettes, an enciphered line, and faint pencil solids
A crowded sheet of geometric quadrature studies: circles quartered and quadrupled so that removing four portions from the greatest circle leaves a square, together with clusters of curvilinear lunes (bisangoli) and the demonstration that 8 lunes equal the 4 greatest portions of the greatest circle. Around the figures run knot-like interlace rosettes and a large shell-form spiral, and at the right are faint pencil sketches of gridded spheres, cones, pyramids and hemispheres. A short line of apparently enciphered or nonsensical text sits in the lower corner, and further faint, untranscribed pencil work is present across the sheet.
On this page
Lunes and the quadrature of the circle
Circles standing in quadruple proportion let the four portions be struck from the greatest circle, leaving a square; abcd are worth the greatest square of the greatest circle. Leonardo further states that the 8 lunes are worth the 4 greatest portions of the greatest circle.
Lunes cannot converge without intersecting
At the mark v, beside a circle carrying six perforated lunes, Leonardo notes that no more lunes can be given in nature converging to one same point without intersecting one another.
Interlace rosettes and a shell-spiral
The upper-left of the sheet carries knot-like interlace rosettes and a large shell-form spiral drawn among the geometric figures, decorative in character.
