And what takes from our armies the capacity to renew their strength is, that provision is now no longer made for one division being received into the ranks of another, which happens because at present an army is arranged for battle in one or other of two imperfect methods.  For either its divisions are placed side by side, so as to form a line of great width but of no depth or solidity; or if, to strengthen it, it be drawn up in columns after the fashion of the Roman armies, should the front line be broken, no provision having been made for its being received by the second, it is thrown into complete disorder, and both divisions fall to pieces.  For if the front line be driven back, it jostles the second, if the second line endeavour to advance, the first stands in its way:  and thus, the first driving against the second, and the second against the third, such confusion follows that often the most trifling accident will cause the ruin of an entire army.

At the battle of Ravenna, where M. de Foix, the French commander, was slain, although according to modern notions this was a well-fought field, both the French and the Spanish armies were drawn up in the first of the faulty methods above described; that is to say, each army advanced with the whole of its battalions side by side, so that each presented a single front much wider than deep; this being always the plan followed by modern armies when, as at Ravenna, the ground is open.  For knowing the disorder they fall into on retreat, forming themselves in a single line, they endeavour, as I have said, as much as possible to escape confusion by extending their front.  But where the ground confines them they fall at once into the disorder spoken of, without an effort to prevent it.

Troops traversing an enemy’s country, whether to pillage or carry out any other operation of war, are liable to fall into the same disorder; and at S. Regolo in the Pisan territory, and at other places where the Florentines were beaten by the Pisans during the war which followed on the revolt of Pisa after the coming of Charles of France into Italy, our defeat was due to no other cause than the behaviour of our own cavalry, who being posted in front, and being repulsed by the enemy, fell back on the infantry and threw them into confusion, whereupon the whole army took to flight; and Messer Ciriaco del Borgo, the veteran leader of the Florentine foot, has often declared in my presence that he had never been routed by any cavalry save those who were fighting on his side.  For which reason the Swiss, who are the greatest proficients in modern warfare, when serving with the French, make it their first care to place themselves on their flank, so that the cavalry of their friends, if repulsed, may not throw them into disorder.

But although these matters seem easy to understand and not difficult to put in practice, none has yet been found among the commanders of our times, who attempted to imitate the ancients or to correct the moderns.  For although these also have a tripartite division of their armies into van-guard, main-body, and rear-guard, the only use they make of it is in giving orders when their men are in quarters; whereas on active service it rarely happens that all divisions are not equally exposed to the same onset.