Harry saw that it was only a matter of minutes before the barricade at the entrance to the keep would be blown in. He utilized the time by bringing down a further supply of stones from the battlements and storing them within easy reach of the inner stairway. He could not prevent the explosion, or raise further obstacles to the progress of the besiegers; he could but defend every inch of the staircase, and retreat, if it must be so, step by step to the top of the keep. Almost despairing now of relief, he was prepared to fight to the end, and, looking round on his little group of stalwarts, he saw no sign of wavering on their part. Eugene’s men were worthy of their master. Half an hour passed; the pause lengthened itself to an hour; yet the train had not been fired, the attack had not been renewed. Had the enemy some still more desperate device in preparation? Instinctively he looked far out over the country; but through the sun-shot haze he descried no sign of a friendly force. Then the watchman whom he had left on the roof saw a thin ribbon of flame dart from the outer gateway, along the wall, to the barred doorway of the keep. There was a deafening roar, followed by the crash of ruining stone-work and the vociferations of the exultant forayers, who swarmed forward to clear away the rubbish. Their ingenuity was inexhaustible. When the mingled smoke and dust had eddied away, Harry saw that they bore with them stout shields of wood, each carried by two men, intended to ward off the missiles he was preparing to launch upon them as they mounted the winding stairs. This was the explanation of their long stillness. Running down, he heard from his left the din of fierce strife in the stairway leading to the dungeons. The enemy were attacking at both points simultaneously.