Machines for defending walls and handling bombards
Devices to throw down scaling ladders, sweep the battlements and move a cannon
A crowded sheet of siege and counter-siege devices. Several mechanisms defend a wall's parapet: a crank (a) that throws down every ladder leaning against the walls, a beam that sweeps the battlements clean of attackers, geared rotating posts that spin ten times for one turn of a wheel to keep men off a bastion, and screws that jam a crossbar into a castle gate silently. Others handle artillery: a pivoted mount, a cart to raise a bombard, pincers to grip it, and a bombard built so it does not recoil when fired.
On this page
Crank a that throws down scaling ladders
The upper-left mechanism is worked by a crank marked a. By pulling it, every ladder that attackers have set against the walls is made to fall to the ground.
Beam that sweeps the battlements
A device toward the centre is described as an instrument that sweeps the merlons so thoroughly that no attacker can gain a footing on them.
Geared spinning posts: ten turns to one
If the pinion below has 10 teeth and the driven wheel 100, the upright posts spin ten times for a single turn of the wheel. This geared-up instrument keeps anyone from climbing onto a bastion.
Four screws to jam a castle gate
With four screws the crossbar in front is driven fast against a castle gate, so the gate cannot be opened — and the whole operation is done without noise.
Cart and pincers to raise a bombard
Near the lower centre a cart is designed to raise a bombard up off the ground. A related sketch below shows a kind of pincers meant to grip the bombard for handling.
A bombard that does not recoil
In the lower-right corner is a bombard designed so that it does not run backwards when it fires, with a pivot (bilico) detailed for the artillery piece.