Teeth 200 - braccia 16 - 4 staves A - N M braccio 1 - 50 pounds - B braccia 8 - P G 1200 pounds - cause of the motion - S D

This instrument must be composed in this form: you will make the first motion, that is the lever B, 8 braccia, and the lantern pinion N with 4 staves, and the greater wheel with 200 teeth, and the pulley M of 1 braccio, and the weight thrown by the sling of 50 pounds; and the weight that falls, which is the cause of the throwing, shall be 1200 pounds.

So that the counterweight which falls does not deliver its blow upon the cord that holds it, you will make the cord one braccio, which is the distance the stone falls. Otherwise everything would break.

E

Pole (axle) of the lantern pinion.

Method of releasing (shooting).
So that the shaft of the sling, together with its wheel and the beam, may go on turning in its course after the release of its stone, you will do thus: first place above, beneath the greater wheel, a ring to which is attached the cord that holds the counterweight. When the sling has thrown, the said cord is found on a level line with its ring and with the top of the pulley; whence the shaft can turn freely in its ring. And when you wish to load it, lower the greater wheel by turning the screw that is beneath its beam, so that the notch which receives the cord is found level with the top of the pulley; and then put the said cord in that notch which the greater wheel has at the point A; and then give the wheel a full turn with the lever B; then lower the beam with its screw at the foot, so that the ring is found at the height of the top of the pulley or higher; then fix the lever B at the point P and pull the cord which has an S at its end; and the timbers of the lantern pinion will draw up to the beam at the point D, and the upper lantern pinion will come out of the teeth of the wheel, which is pivoted at the point N, and stays in the manner of the figure alongside, marked above E. And thus it will release ...ra.

G - F - P O - E BCAD
A B are those wheels that load the crossbows, when their tooth does not let [the cord] run past, by reason of the spring, as is figured at the point p, which makes them turn one step with the stile D E. And when you have drawn the cord to the nut with the instrument G, and you wish to wind the cord back to reload the other crossbow, then pull the ring F, and the springs will come out of the points, or notches, O P, and the two wheels A B will turn upon the stile D E, and you will lengthen the cord to the instrument G, and the wheel C is free of itself.