Notes on a machine for digging and hauling earth
Crossed-out drafts praising its advantages over a rival's device
This sheet, rotated ninety degrees, is dominated by two long crossed-out drafts praising a machine for digging and hauling earth. Leonardo lists its advantages — the earth falls of itself into a box, the wheel always turns one way, it is worked by a single man, and it throws the earth up in two stages — and enumerates the defects of an earlier version. In a second passage he compares it favourably with a rival device of one 'Pesero', claiming his two men move 400 pounds of earth where barrow-carriers move only 150. A framework machine is sketched at the top of the sheet.
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A wheel and self-emptying box worked by one man
The instrument's advantages: the earth goes by itself into the box, the wheel always turns one way, it is moved by a single man, and it throws the heaped earth up in two stages. The full box empties itself and returns empty to be refilled, so that as one goes out full the other comes back empty, without loss of time.
Moving more earth with fewer steps than Pesero's device
Leonardo faults Pesero's machine for raising the load higher than needed and then lowering it, so the men walk twenty superfluous paces. Where barrow-carriers convey 150 pounds of earth onto the embankment with great effort, his two men convey 400 pounds without effort.
The framework machine sketched at the top
At the head of the sheet a framework machine is drawn, with a wheel, arms, and supporting structure — the earth-moving device described in the accompanying notes.