Discourses on Fortifications

and I conclude that to add defenses to the faces of the bastions, I would take a method far removed from this, as I will demonstrate in another place in these discourses.

A geometric plan of a fortification bastion with a flat face and two flanking sides.

Others have praised this following method for the multiplication of defenses, which, however, for the aforementioned reasons, is worse.

A geometric plan of a complex fortification bastion with multiple stepped flanking sides.

Others have liked the following method more, because there is no part of the enclosure that is not cleared by two flanks. But anyone who has read the beginning of these Discourses will easily be able to realize the defects without me multiplying words on every minor detail.

A geometric plan of a fortification bastion with a pointed face and two flanking sides.

Others would like to proceed as shown in the following plan, thinking that the space between the bastions is secure and that the bastions are larger and more perfect because they approximate the circular shape. And to me, this method of building seems not only poor but very bad. Because, in addition to the reasons given elsewhere, the expense is multiplied, the enclosure is made large and with little capacity, and the weakest parts (due to the great distance from those flanks that are to defend them) will be almost devoid of defenses. And by making the bastions closer together, instead of a remedy, greater damage will be caused, for reasons I have mentioned many times. Such that I cannot consider how so many flanks and turnings can help me if, despite them, the enemies can achieve their intent by way of the bastions themselves; unless the bastion had some hidden privilege that prevented one from being able to assault it. Furthermore, by the shot A, one can know that the bastions do not come out larger, and that whenever we resolve to make the exterior angle of the bastion cleared absolutely by the flank of the other bastion, and the remainder by the flanks of the large curtain, as seen in the following plan, the bastions not only turn out smaller in body, but in flanks as well. And I believe that some, for this particular detail, praise this fifth plan more than the third, because since the bastions are not cleared at their extremities by the flanks B and C, they turn out better. But it is to be noted that if this is true, they are also less defended. Furthermore, wishing to proceed in this manner, or in the way shown in the third plan, to make the bastions able to reveal one another, it is forced, in order to make the moat of just width before their faces, that it be very wide in the middle. This, in addition to the expense, can cause great convenience for the enemies.