Pulleys and windlasses for raising weights and earth
The longer the path the lighter the load; hands move three braccia to raise the weight one
A large wheel and several small sketches of pulleys (carrucole) and a windlass (verricello) study the raising of weights and of earth. A cancelled note, written over a small map sketch, states the principle that among equal loads raised to the same height the one that moves through a longer path is made lighter. With the windlass-and-pulley the hands travel three braccia while the weight rises one, and in another arrangement the power equals the resistance. Leonardo praises the method of raising earth in which the lifting instrument has least to be filled and emptied.
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The longer the path, the lighter the load
Among movable loads equal to their motors that must be raised to the same height, the one made lighter is that which moves through a longer path. The note is cancelled and written over a small cartographic sketch.
Windlass and pulley: three braccia to one
With the windlass and pulley the hands travel three braccia when the weight they pull rises a single braccio, a threefold mechanical advantage.
Raising earth with least filling and emptying
In one pulley arrangement the power is equal to the resistance. The most praiseworthy way of raising earth is that in which the instrument that lifts it has least to be filled and emptied.