force him to evacuate this place we shall have gained a strategical point whence Hsüch‘ang can be attacked.”
Yüan adopted this suggestion. From each of the camps they sought out the strongest veterans who dug with iron spades and carried earth to raise mounds near Ts‘ao’s camp.
Ts‘ao’s men saw what their enemies were doing and were anxious to make a sortie and drive them off. But the archers and crossbow men came out commanding the narrow throat through which it was necessary to attack and stayed them. At the end of ten days they had thrown up more than half a hundred mounds and on the summit of each was a lofty tower, whence the archers could command their opponents’ camp. Ts‘ao’s men were greatly frightened and held up their bucklers to keep off the various missiles. From the mounds the arrows flew down, pang! pang! like a fierce rain. The men of the Yüan army laughed and jeered when they saw their enemies crouching under their shields and crawling on the ground to avoid their missiles.
Ts‘ao saw that his soldiers were getting out of hand under this attack so he called a council. Liu Yeh spoke up saying, “Let us make ballistæ and so destroy them.”
Ts‘ao at once had models brought and set cunning workmen to make these machines. They soon constructed some hundreds and placed them along the walls of the camp inside, just opposite the high ladders on the enemy’s mounds.
Then they watched for the archers to ascend the towers. As soon as they began to shoot all the ballistæ began to heave their stone balls into the skies and they wrought great havoc. There was no shelter from them and enormous numbers of the archers were killed. Yüan’s men called these machines “Rumblers” and after their appearance the archers dared not ascend the mounds to shoot.
Then Shên P‘ei, the strategist, thought out another plan. He set men to tunnel under the walls into the midst of Ts‘ao’s camp and called this corps “The Sappers.” Ts‘ao’s men saw the enemy digging out pits behind the mounds and told the chief, who at once sought a counter plan from Liu Yeh.
“As Yüan Shao can no longer attack openly he is attacking secretly and is tunnelling a road under ground into the midst of our camp,” said he.
“But how to meet it?”
“We can surround the camp with a deep moat which renders their tunnel useless.”
So a deep moat was dug as quickly as possible and when the enemy sappers arrived thereat, lo! their labour had been in vain and the sap was useless.
It is recorded that Ts‘ao held Kuantu throughout the eighth and ninth months when, the men being worn out and provisions failing, he began to think of giving up and returning to the
