9. The Army on the March
The contents of this interesting chapter are better indicated in ss. 1 than by this heading.
1
Sun Tzu said: We come now to the question of encamping the army, and observing signs of the enemy. Pass quickly over mountains, and keep in the neighborhood of valleys. #
The idea is, not to linger among barren uplands, but to keep close to supplies of water and grass. Cf. Wu Tzu, ch. 3: "Abide not in natural ovens," i.e. "the openings of valleys." Chang Yu tells the following anecdote: Wu-tu Ch`iang was a robber captain in the time of the Later Han, and Ma Yuan was sent to exterminate his gang. Ch`iang having found a refuge in the hills, Ma Yuan made no attempt to force a battle, but seized all the favorable positions commanding supplies of water and forage. Ch`iang was soon in such a desperate plight for want of provisions that he was forced to make a total surrender. He did not know the advantage of keeping in the neighborhood of valleys."