Faint ruled lines and compass circles (verso)
Instrument-drawn construction lines revealed only after restoration
Before restoration this verso looked blank; it is in fact covered with very faint lines and circles laid down with instruments rather than freehand, as the transcribed note records. Ruled rectilinear figures and diagonals fill the upper half of the sheet, with small compass-drawn circles at the lower left. The Ambrosiana catalogues the leaf with designs for cranes, for gripping large stones, and a retaining wall.
On this page
Faint instrument-drawn lines and circles
The page carries very faint lines and circles set out with a straightedge and compass rather than freehand, invisible before the sheet was restored. Ruled rectilinear figures cross the upper half and small circles appear at the lower left.