Percussion of Two Equal Falling Bodies
A marginal scale of descent points; impact grows with the length of the fall
A single ruled proposition holds that when two bodies identical in shape and weight descend one after another, the ratio of their impacts equals the ratio of the lengths of their motions. Along the outer margin two small circles at the same height sit above two columns of seven dots each, marking successive degrees of descent as a graded scale, with one extra dot adding a further degree. The sheet belongs to Leonardo's study of percussion and accelerated motion.
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Impact in proportion to the length of the fall
When two bodies of equal shape and weight descend, one having begun its motion before the other, their impacts stand in the same proportion as the lengths of their respective motions. The later-starting body, having fallen through a shorter path, strikes with correspondingly less force.
Marginal scale of descent degrees
In the outer margin two small circles stand at the same height, and beneath them run two columns of seven dots apiece, each dot marking one further degree of descent. A single dot set above the second column adds one more degree, so the fall is laid out as a series of equal steps.