"Therefore we conclude that it is not the strong walls that resist against great percussions, but it is the hay that calms the fury of the balls shot by powerful artillery"
Leonardo probably conceived this drawing during the period spent in Romagna working for Cesare Borgia. It is a study on the possibility to use a ravelin not only as a defensive structure, but also as an outpost from where to attack the enemy with shots at ground level. In the middle of the ditch there is a low tower with a large diameter and a conical superstructure. It has an underground access and a fire line at the level of the water surface. The external walls are covered with hay in order to buffer the artillery blows. This is a new idea of offensive structure, hardly attackable by those firearms already in use at the end of the XV century.
The model is based on the drawing:
- Codex Atlanticus f. 116 r. (1502-1503)
Milano, Biblioteca Ambrosiana