The Chinese here is tricky and a certain key word in the context it is used defies the best efforts of the translator. Tu Mu defines this word as "the measurement or estimation of distance." But this meaning does not quite fit the illustrative simile in ss. 15. Applying this definition to the falcon, it seems to me to denote that instinct of SELF RESTRAINT which keeps the bird from swooping on its quarry until the right moment, together with the power of judging when the right moment has arrived. The analogous quality in soldiers is the highly important one of being able to reserve their fire until the very instant at which it will be most effective. When the "Victory" went into action at Trafalgar at hardly more than drifting pace, she was for several minutes exposed to a storm of shot and shell before replying with a single gun. Nelson coolly waited until he was within close range, when the broadside he brought to bear worked fearful havoc on the enemy's nearest ships.