Trading time, force, motion and weight to lift a load
Four powers each set at 10 degrees, with reciprocal rules for doubling and halving
A text-only page (with a short vertical column of labels) in which Leonardo sets four quantities — time, force, motion and weight — each at 10 degrees, and asks how to raise the weight. He then states a set of reciprocal rules: doubling the weight while holding force and motion fixed requires doubling the time; doubling it while holding time and force fixed requires halving the motion; doubling it while holding motion and time fixed requires doubling the force; and halving the weight halves the force. It is an early attempt to book-keep the trade-offs among the mechanical powers as proportions.
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Raising a weight with four powers at ten degrees each
Leonardo posits 10 degrees each of time, force, motion and weight, and asks how to lift the weight. If the weight is doubled without changing force or motion the time must be doubled; if doubled without changing time or force the motion must be halved.
Reciprocal rules among the mechanical powers
The relations are given as reciprocal proportions: to double the weight while holding motion and time fixed the force must double, and halving the weight halves the force. The four starting values are set out in a short column (force 10, time 10, motion 10, weight 10).