Measuring a Crossbow's Force by an Equivalent Weight
Equating the draw-weight to all the arrows laid along the shot's path
This full page of mirror-script continues Leonardo's study of a crossbow's force. He argues that the weight needed to draw the cord to the middle of its rise equals the combined weight of all the arrows that could be laid end to end along the arrow's whole flight-path, then asks how the reckoning would change for an arrow that is thin and long, short and thick, or a leaden ball, urging that a general rule be made of this 'subtle matter.' Faint further writing not included in the transcription is also visible lower on the leaf.
On this page
Draw-weight equals all the arrows along the flight-path
Leonardo says that the weight required to draw the cord to the middle of its rise equals the combined weight of every arrow that could be laid end to end along the whole path the arrow travels when shot, from the catch of the crossbow to its farthest course. He then asks how one would measure an arrow that is thin and long, short and thick, or a leaden ball, all along its path, and calls for making a general rule of this subtle matter.