Why an oblique suspended rod rights itself
Gravity acts throughout the whole support, and the pivot's imperfection turns the rod
A diagram of an oblique rod hung within a vertical frame (labelled a, n, m, o, q, p) accompanies two propositions on weight. Leonardo first states that gravity is entire through the whole length of a support and entire in every part of it. He then poses a question: why, in experiment, does a rod set on an oblique line, with its parts equally distant from the central line, not stay oblique but instead align itself and meet the central line at four right angles? The answer he gives is that this arises from the imperfection of the pivot.
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Gravity acts entire through the whole support
Leonardo states that gravity is entire throughout the whole length of its support and entire in every part of that support. Weight is thus not concentrated at a point but present wholly along the beam that carries it.
The oblique rod rights itself: imperfection of the pivot
He asks why a rod set on an oblique line, its parts equally distant from the central line, does not stay oblique but aligns itself and coincides with the central line at four right angles. His answer is that this behaviour arises from the imperfection of the pivot (the pole).