“Method for emptying a port: Make it so that this is forty braccia per face, and when you have emptied the bottom of this case, let one of the faces remain, and change the positions of the other three beyond that one, and do as many again; and then, empty again, and do the same.”
The caption that goes with this drawing reads modo di votare un porto "how to dry up a port", that is how to facilitate the works for building submersed foundations or for deepening the port's bottom. Draining a portion of water helps excavate the depth. The equipment consists of a caisson made up of movable bulkheads mortised into each other, driven into the sea-bed and connected with each other via four quadrangular posts. Part of the bulkhead module and a section of the quadrangular post are constructed in an enlarged separate version.
The model is based on the drawing:
- Manuscript B f. 6 r. (1487-1490)
Paris, Institut de France