Towers, Casemates, and a Sheltering Harbour Wall
Solid flanking towers, a corner-pyramid keep, and a mole a b that shelters a port
The right-hand page turns from sea-foundations to fortification and harbour defence. High, thick, wholly solid towers with flank defences and casemates at their base are recommended to withstand siege machines, and a square tower crowned with corner pyramids and packed with stairs, double bridges, reversed entrances, ravelins and ditches is praised as strongly resistant. A further note designs a port whose long, chalice-scarped wall a b, set 250 feet inside the entrance, gives strength, breaks the waves, and serves as a beacon, while a second port is flushed clean by landward floodgates. Pen sketches show towers, a triangular tower, and harbour plans.
On this page
Solid towers with flank defences and base casemates
The towers should be high, thick and wholly solid so as to resist siege machines, with defences set in the flanks and along the sides of the walls. The approach to the casemates ringed around the base of the towers is reached through these flanking works.
A square tower with corner pyramids and internal traps
A square tower carrying pyramids on its corners, subdivided into many recesses such as stairs, gates, double bridges, reversed entrances, ravelins and ditches, is judged to be of great resistance in itself. The internal divisions multiply the obstacles an attacker must overcome.
The harbour wall a b and flushing floodgates
In one port a wall labelled a b, 80 feet thick and 300 feet long and scarped like a chalice, is placed 250 feet inside the entrance: it gives strength, sustains the waves, acts as a beacon, and keeps the port safe from every wind. Another port has two floodgates on the landward side of its walls that, when opened, let the storm scour and wash the harbour clean of all filth.
Diagram lettered a and b
A small figure at the centre right carries the letters a and b, keyed to the harbour design in which the wall a b protects the basin. The plans drawn on the sheet show the curved and angled works of these fortified ports.