7. In crossing salt-marshes, your sole concern should be to get over them quickly, without any delay.
[Because of the lack of fresh water, the poor quality of the herbage, and last but not least, because they are low, flat, and exposed to attack.]
8. If forced to fight in a salt-marsh, you should have water and grass near you, and get your back to a clump of trees.
[Li Ch’uan remarks that the ground is less likely to be treacherous where there are trees, while Tu Mu says that they will serve to protect the rear.]
So much for operations in salt-marshes.
9. In dry, level country, take up an easily accessible position with rising ground to your right and on your rear,
[Tu Mu quotes T’ai Kung as saying: "An army should have a stream or a marsh on its left, and a hill or tumulus on its right.">[
so that the danger may be in front, and safety lie behind. So much for campaigning in flat country.
10. These are the four useful branches of military knowledge
[Those, namely, concerned with (1) mountains, (2) rivers, (3) marshes, and (4) plains. Compare Napoleon’s "Military Maxims," no. 1.]