"I am afraid it is the disaffection among their officers that is paralysing them," Terence said. "But I quite admit that it may be good policy to keep the men under cover. They really could do no good against the French batteries; which have all the advantage of position, as well as numbers and weight of metal; and it would certainly be well to reserve the troops till the French drive their trenches close up. If I thought that the silence of the guns on the walls were due to that, I should be well content; but I am afraid it is nothing of the sort. If the French keep up their fire, as at present, for another forty-eight hours, the place will throw open its gates. The inhabitants must be suffering frightfully. Of course, if Colonel Cox had men he could thoroughly rely upon, he would be obliged to harden his heart and disregard the clamour of the townspeople for surrender; but as the garrison is pretty certain to make common cause with them, it seems to me that the place is lost, if the bombardment continues." In a short time, seeing that the working parties in the enemy's trenches made no attempt to push them farther forward, Terence withdrew the men from their exposed position on the ramparts--leaving only a few there on the lookout--and told the rest to lie down on the inner slopes, so as to be in shelter from the French fire. Bull was in command of the force in the other redoubt, which was a quarter of a mile away. The redoubts were, however, connected by a deep ditch, so that communication could be kept up between them, or reinforcements sent from one to the other, unobserved by the enemy, except by those on one or two elevated spots. All day the roar of the cannon continued. From a dozen points, smoke and flame rose from the city, and towards these the French batteries chiefly directed their fire, in order to hinder the efforts of the garrison to check the progress of the conflagration. Just after dark, as Ryan and Terence were sitting down in an angle of the bastion to eat their supper, there was a tremendous roar; accompanied by so terrible a shock that both were thrown prostrate upon the ground with a force that, for the moment, half stunned them. A broad glare of light illuminated the sky. There was the rumble and roar of falling buildings and walls; and then came dull, crashing sounds as masses of brickwork, hurled high up into the air, fell over the town and the surrounding country. Then came a dead silence, which was speedily broken by the sound of loud screams and shouts from the town. "It is just as we feared," Terence said as, bruised and bewildered, he struggled to his feet. "The magazine in the castle has exploded."