Blank verso of folio 149
One half-leaf holds two insignificant pen strokes, the other nothing; only show-through of the recto's crossbow
Both half-leaves of this verso are essentially blank and were invisible before restoration: one carries only two insignificant pen strokes, the other no writing or drawings at all. The page shows faint show-through of the great crossbow and war-engines drawn on the recto, and the Ambrosiana catalogue classifies the sheet under geometry — the equivalence of surfaces and circles divided into equal parts.