Fortress tower, mountain ditch, and counterweighted drawbridges
Defensive details for a rocca: a tiered tower, a dry ditch, and two gate bridges
Four labelled sketches gather details of a fortified place: a tiered crenellated tower whose lowest storey is to be built entirely solid, and a scheme for cutting a waterless ditch into mountainous ground. Two drawbridge designs follow: one meant to stand before the doorway of a rocca, the other with its counterweights hidden inside the gate between double walls. Fine mechanical drawings at the foot of the sheet show the bridges' pivoting arms and counterweight wheels.
On this page
Tiered tower with a solid lowest storey
A stepped, crenellated tower drawn in perspective, tapering upward stage by stage. The note directs that its first level be built entirely solid rather than hollow.
Waterless ditch cut in mountainous ground
A part of a fortress is shown with a sloping glacis running down to a triangular ditch. The note gives the way to make such a ditch without water where the terrain is mountainous.
Drawbridge before a fortress gate
A pivoting bridge is drawn in elevation. The caption calls it a bridge well suited to stand before the doorway of a fortress.
Drawbridge with hidden counterweights
Two mechanical studies at the foot of the sheet show the bridge deck, its pivoting arms and a counterweight wheel. The note explains that this bridge carries its counterweights in the flanks, inside the gate, between two double walls.