Boat-borne dredging machines built around spoked wheels
A note that one third must project out beyond the bank
On a red-prepared sheet, pen drawings show two overlapping boat- or hull-shaped excavating machines, each framed around a large spoked wheel and worked by cranks and a windlass, with small gallows-like frames and loose fittings sketched above and to the side. A single line of mirror-writing at the top gives a proportion for how far part of the structure must jut out. Such wheeled, hull-mounted rigs belong to Leonardo's schemes for dredging or excavating channels and riverbanks.
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One third to project beyond the bank
The line at the top sets a working proportion: one third of the member is to project out past the bank or edge. It fixes how far the machine or its beam overhangs the water it is to work.
Hull-frames turning on large spoked wheels
Two boat-like frames overlap, each carrying a big spoked wheel worked by cranks and a windlass. The curved hulls and radiating spokes suggest a rotating bucket- or paddle-wheel driven by hand to lift material as the rig floats.
Gallows frames and loose fittings
Above the machines are two small trestle- or gallows-like frames with hanging members, and toward the right edge a few loose fittings and a screw-like form are jotted separately.