The blow amplified by a rebound motion
Percussion mechanics with a pivoted striking apparatus, plus a fortification note
Folio 32r studies the mechanics of percussion: the main note argues that a blow is increased by a rebound or 'reflex' motion and by a longer lever, comparing the line n c against the line a n. A red-chalk sketch sets out the striking apparatus, which Leonardo says should be drawn as two separate cases. A marginal line treats pits dug in the earth as quarters for a garrison's provisioned men, and a short column of figures accompanies the calculations.
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The blow amplified by a rebound (reflex) motion
If a strikes b it rebounds forcefully to a and delivers a great percussion from d to f; were the percussion instead from c to d, the blow would fall from d to f with great fury. The percussion c-d is greater than a-b because it springs from a greater lever, as the line n c shows against the line a n, and striking both faces makes the blow more powerful still.
Pivoted striking apparatus drawn as two cases (d, n c, a d, b f)
A note states that these are two cases and that two figures should therefore be drawn. The accompanying red-chalk sketch of a forked, pivoted striking mechanism is labelled d, n c, a d, b f to key it to the percussion argument.
Pits in the earth as quarters for provisioned men
Beside a numbered figure a line notes that pits dug in the earth serve as the place for the rooms of provisioned men, lodgings and stores for a garrison. The figures 110, 40 and 425 are set against it.
Column of figures (440, 5620, 174080, 2720, 6444)
A short column of calculation stands at the right of the sheet, listing 440, 5620, 174080, 2720 and 6444. The numbers accompany the excavation and fortification estimates worked out on the surrounding leaves.