On Motion: Bows and Crossbows as a Test of Force
Do two bodies at double the speed travel double the distance? The varied carry of long and short bows
Under the heading 'De moto' Leonardo asks whether two bodies of equal shape, weight and material, one at double the other's speed, will cover double the distance. He answers empirically from archery: bows or crossbows with long arms give a great but slow carry, while short thick arms give a fast, short one, the short bow driving hardest in the middle third of its stroke. He calls for all the mathematical forces to be demonstrated, since crossbows vary endlessly in draw, length, thickness and breadth, and concludes that the more a single mover accompanies a body, the farther it drives it.
On this page
Does double speed mean double distance?
Leonardo asks whether two moving bodies of equal figure, weight and material, one of double velocity, will make double the journey of the other or not. The whole page tests this proportional question against the observed behaviour of shooting weapons.
Long slow carry versus short fast carry
Bows and crossbows with long arms make a great but slow carry, while those with short, thick arms make a fast, short one; the short bow's percussion drives farthest in the third of its motion. Because these weapons vary in draw, length, slenderness, thickness and breadth, all the mathematical forces must be demonstrated to explain their many varied effects.
