Excavation costing for the fortress ditch
Red-chalk earthworks and a wheeled timber frame beside the arithmetic for digging the ditch
Red-chalk sketches on this recto show sloping fortification earthworks, a heavy wheeled timber frame, and a small tripod-like structure with radiating lines. The accompanying note continues the ditch calculation from the facing page: a depth of 210 braccia multiplied by the ditch's length of 275 braccia yields 57750 square braccia, which divided by the terrain-canna of 64 braccia gives about 902 canne, and so 902 ducats. A block of long multiplication and division at lower right works the figures through.
On this page
Reckoning the excavation of the fortress ditch
The note continues a calculation from the facing sheet: the depth of 210 braccia multiplied by the ditch's length of 275 braccia gives 57750 square braccia, which divided by the terrain-canna of 64 braccia yields 902 22/64 canne, taken as as many ducats as there are canne, that is about 902 ducats.
Red-chalk fortification earthworks and a wheeled frame
Sketched in red chalk are sloping ramparts and a fortified slope, a heavy wheeled timber frame with a triangular braced structure at the top of the sheet, and a small tripod-like device with radiating lines below. The drawings are not accompanied by transcribed captions.
Long multiplication and division of the ditch volume
The lower right carries the worked arithmetic behind the ditch estimate, with products building up to 60500 and divisions dropping out canne and ducats.