Close up against the face of the wall itself was pushed a movable screen, called the "cat," the object of which was to protect John de Standen and his men as they carried on their work of undermining the walls.

Ralph was ordered by his superior officer, a grim old baron who had been one of those assembled at Runnymede when John signed the charter, but who now supported his son, to pay special attention to the mining operations. To Ralph and John de Standen attached himself one who could hardly be called a soldier, though he exhibited all the courage and zeal which are the necessary qualities of a man of war. This was the young lay-brother from St. Alban's. He was received as a sort of volunteer, and was granted permission to serve in the mining work, for his religious vows, he said, forbade him to carry sword or spear. This young man proved, however, a valuable assistant.

A kind of friendly rivalry went on between the two branches of warfare into which the besiegers were divided. Those who had charge of the engines favoured the notion of pounding the walls till they battered them down. The sappers and miners, however, built their hopes of reducing the fortress upon their methods of burrowing underneath it. But before these latter were able to push on far with their works, the besiegers above ground gained two important advantages. They carried by assault the barbican or outer defence of the gate, and with but a loss of four or five men. By this means they were able to rush the gate itself, and in a second assault forced their way into the outer bailey or yard, the first one on the west side.

Here were the store-houses, and here also were kept the horses and live stock which the besieged took care to have always within the castle walls. Forage, grain, and such like bulky articles as could not be removed into the keep were likewise stored in the yard. All these fell into the hands of the besiegers, who removed the arms, the horses, and the pigs, and burned the buildings which contained the corn and hay. The besieged retreated within the inner wall, which defended the lesser bailey.

But between the upper and lower bailey there stood--a rather unusual feature in a Norman castle--a strong building known by the name of the "old tower." It had probably something to do with fortifications which at an earlier date protected the bridge across the Ouse, before the castle precincts were prolonged westwards. Here the besieged gathered in strength and made an obstinate stand.

The assistance of John de Standen and his men was now necessary. The other defences, the barbican and the wall of the outer bailey, had been carried by assault, the soldiers climbing the walls and forcing their way within. But the wall which separated the two baileys, protected as it was by the old tower, proved a more formidable obstacle. The king's troops intrenched themselves in the outer bailey, and the cat was wheeled into position ready for the operations of the miners.

These latter worked with a will. Ere long they were able to report to Ralph de Beauchamp, as their superior officer, that the foundations of the old tower were undermined, and that the building would fall directly the stays and struts with which they had propped it up should be removed.

So Ralph went down into the mine with John de Standen, that he in his turn might report to his superiors that the underground work was indeed finished, and that the soldiers might be held in readiness to storm the inner bailey.

With some professional pride the king's miner conducted the knight through the dark passages he had burrowed, explaining as he went the manner in which the supports should be removed directly he received the signal to do so.

They were just beneath the old tower, and John de Standen was enlarging on the excellent arrangements which he had made for the overthrow of the building, when, to their intense astonishment, a woman's voice was heard speaking in the vault overhead.