Impact and rebound: colliding bodies and trebuchet throw
Definitions of blow and bounce, counterweight range of catapults, and proportional rebound
A page mainly headed Colpo (impact) with a marginal quarter-arc figure labelled 'water' and figure number 35. Leonardo defines a blow as the terminus of motion in an indivisible time and a bounce as the terminus of a blow, then states that a trebuchet, bricola, or mangonel throws its weight farther the farther its counterweight moves from the centre of movement. Several propositions give the rebound of colliding bodies in proportion to their diameters or their driving powers, closing with the case where a striking body transfers its whole motion to an equal body and comes to rest in the struck body's place.
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Blow and bounce defined
A blow is the terminus of motion caused in an indivisible time; a bounce is the terminus of a blow. These definitions open the sequence of impact propositions.
Range of trebuchet, bricola, and mangonel
The siege engine (trebuchet, bricola, or mangonel) throws its weight farther when, in its motion, the counterweight that drives it draws farther from the centre of movement.
Proportional rebound of colliding bodies
For two bodies driven by equal power to their percussion, the bounce of the lesser weight to the greater keeps the proportion of their diameters; with doubled or unequal driving powers the rebounds scale accordingly.
Transfer of motion between equal bodies
If the striker's continuous centre of motion is aimed at the centre of a similar body, the struck body follows the striker's course while the striker itself comes to rest in the place the struck body had held.
Quarter-arc figure labelled 'water'
The upper-right margin bears a curved quarter-arc figure with the label 'water' inside it, set beside the figure number 35, apparently a study of a curved channel or falling stream accompanying the impact notes.