- A large river which crosses the direction of the attack is always very inconvenient for the assailant: for when he has crossed it he is generally limited to one point of passage, and, therefore, unless he remains close to the river he becomes very much hampered in his movements. Whether he meditates bringing on a decisive battle after crossing, or may expect the enemy to attack him, he exposes himself to great danger; therefore, without a decided superiority, both in moral and physical force, a general will not place himself in such a position.
- From this mere disadvantage of placing a river behind an army, a river is much oftener capable of defence than it would otherwise be. If we suppose that this defence is not considered the only means of safety, but is so planned that even if it fails, still a stand can be made near the river, then the assailant in his calculations must add to the resistance which he may experience in the defence of the river, all the advantages mentioned in No. 1, as being on the side of the defender of a river, and the effect of the two together is, that we usually see generals show great respect to a river before they attack it if it is defended.
But in the preceding book we have seen, that under certain conditions, the real defence of a river promises right good results; and if we refer to experience, we must allow that such results follow in reality much more frequently than theory promises, because in theory we only calculate with real circumstances as we find them take place, while in the execution, things commonly