Isolating him from his allies. We must not forget that Sun Tzŭ, in speaking of hostilities, always has in mind the numerous states or principalities into which the China of his day was split up. the next in order is to attack the enemy’s army in the field; When he is already in full strength. and the worst policy of all is to besiege walled cities. The use of the word 政 is somewhat unusual, which may account for the reading of the modern text: 其下攻城. 4. 攻城之法爲不得已修櫓轒轀具器械三月而後成距闉又三月而後已 The rule is, not to besiege walled cities if it can possibly be avoided. Another sound piece of military theory. Had the Boers acted upon it in 1899, and refrained from dissipating their strength before Kimberley, Mafeking, or even Ladysmith, it is more than probable that they would have been masters of the situation before the British were ready seriously to oppose them. The preparation of mantlets, movable shelters, and various implements of war, will take up three whole months; It is not quite clear what 櫓 were. Ts‘ao Kung simply defines them as 大楯 “large shields,” but we get a better idea of them from Li Ch‘üan, who says they were to protect the heads of those who were assaulting the city walls at close quarters. This seems to suggest a sort of Roman _testudo_, ready made. Tu Mu says they were “what are now termed 彭排” (wheeled vehicles used in repelling attacks, according to K‘ang Hsi), but this is denied by Ch‘ên Hao. See _supra_, II. 14. The name is also applied to turrets on city walls. Of 轒轀 (_fên yün_) we get a fairly clear description from several commentators. They were wooden missile-proof structures on four wheels, propelled from within, covered over with raw hides, and used in sieges to convey parties of men to and from the walls, for the purpose of filling up the encircling moat with earth. Tu Mu adds that they are now called 木驢 “wooden donkeys.” Capt. Calthrop wrongly translates the term, “battering-rams.” I follow Ts‘ao Kung in taking 具 as a verb, co-ordinate and synonymous with 修. Those commentators who regard 修 as an adjective equivalent to 長 “long,” make 具 presumably into a noun. and the piling up of mounds over against the walls will take three months more. The 距闉 (or 堙, in the modern text) were great mounds or ramparts of earth heaped up to the level of the enemy’s walls in order to discover the weak points in the defence, and also to destroy the 樓櫓 fortified turrets mentioned in the preceding note. Tu Yu quotes the Tso Chuan: 楚司馬子反乘堙而窺宋城也. 5. 將不勝其忿而蟻附之殺士三分之一而城不拔者此攻之災 The general, unable to control his irritation, will launch his men to the assault like swarming ants,