90 Chapter Three
experimenting for half a century in desultory fashion with ways to
make old fortifications better able to withstand gunfire. After that date
the problem assumed an entirely new urgency for every existing
political authority in Italy. The country’s best brains were devoted
to seeking a solution, including those of Leonardo da Vinci and
Michelangelo.^24
Partly by accident, or perhaps one should say through hasty impro
visation, the Italians quickly discovered that loosely compacted earth
could absorb cannon shot harmlessly. The Pisans, besieged by the
Florentines in 1500, made this discovery when they built an emer
gency wall of earth inside their endangered ring wall. As a result,
when cannon fire brought the stones of their permanent fortification
tumbling down, a new obstacle confronted the besiegers which they
were unable to cross. To make a rampart of earth, one had to dig: and
by shaping the resulting hole in the ground so as to give it a vertical
forward face, the ditch thus formed became a sort of negative, or
inverted, wall, presenting an attacker with a very difficult obstacle,
and one that was entirely proof against destruction by cannon.^25
This fundamental idea, later embodied in more permanent forms,
with masonry facings to the ditch, went far to solve the problem of
how to protect against gunfire. Bastions and outworks, armed with
guns and defended by ditches, were soon added. When properly lo
cated, such outworks could bring a withering crossfire against anyone
trying to cross the ditch and assault the wall. Outworks’ artillery also
had a second role to play, for by directing counter battery fire against
the besiegers’ guns, the accuracy and force of the attack could be
sharply reduced.^26
By the 1520s, fortifications on the new Italian model were again
quite capable of resisting even the best-equipped attackers. But their
cost was enormous. Only the wealthiest states and cities could afford
the scores of cannon and the enormous labor of construction required
by the trace italienne, as this type of fortification came to be called
beyond the Alps.
- Albrecht Dürer, a pupil of Italians in many things, came back from his Italian
travels with an interest in the problem, and has the distinction of having published the
first book on fortification ever printed, Etliche Underricht zur Befestigung der Stett Schloss
and Flecken (Nuremberg, 1527). This volume is more remarkable for the grandiose
works Dürer recommends as protections against cannon than for the practicality of his
designs. Cf. Duffy, Siege Warfare, pp. 4–7.
- Duffy, Siege Warfare, p. 15.
- John R. Hale, “The Development of the Bastion, 1440–1534,” in John R. Hale,
ed., Europe in the Late Middle Ages (Evanston, 111., 1965), pp. 466–94.
