Rebounds of Moving Bodies; Solid Figures Defined
On percussion, impetus and bounce, with cubes, prisms and pyramidal solids
The lower half sets out propositions on the percussion of moving bodies: bodies of equal impetus, shape and weight striking obstacles of equal resistance produce rebounds ('balzi') of differing height and length, and Leonardo reasons about why a greater blow may yield a smaller bounce by distinguishing impetus from percussion. Turned on its side, the sheet gives geometric definitions: a 'pyramidal body' is one whose lines from the base meet in a point and can have no fewer than three sides, and a 'cuneal' (wedge) body is defined in the same way. Above are drawn cubes, boxes and prisms in perspective.
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Rebounds from equal percussions
Among moving bodies of equal impetus, shape and weight striking objects of equal resistance, the one born of a percussion of lesser power will rebound with the longer space. Leonardo explains a greater blow can give a smaller bounce because, for heavy bodies of greater power, impetus outweighs percussion.
Pyramidal and wedge-shaped bodies defined
A pyramidal body is defined as one whose lines departing from the base meet in a point, and which can have no fewer than 3 sides; a 'cuneal' (wedge) body is begun by the same kind of definition.
Solids drawn in perspective
Across the top of the sheet Leonardo draws a row of cubes, open boxes and prisms in perspective, illustrating the solid figures discussed in the text.