For nearly half a minute the two young men waited, holding the massive door in position. Then with a mighty roar and flash the explosion came. The noise was terrific, and the shock made the very earth tremble. The door was blown back flat, dashing the two young men to the ground like straws, and a rush of hot air sped over them like a hurricane. Jumping to their feet the instant it had passed, they lifted the door back into position and held it there, choking and gasping with the thick fumes and smoke of the fiery blast. For a moment there was a calm, followed by the ominous sound of falling objects as the rocks, flung into the air by the explosion, dropped heavily back to the ground. Then all was still again. "Prop this in position while we go back and see how fared the lady Beatrice," gasped Edgar. "If all is well with her, I believe we may yet win through to safety." Back through the passage beneath the moat, now knee-deep in water, the young men pressed. The torch had been blown out by the rush of air, and all was pitchy dark. "Beatrice! Beatrice!" shouted Edgar loudly. "Here--I am safe--but in sore distress," came the reply, and with a cry of triumph Edgar sprang to her side. Half-choked by the smoke and fumes, with torch blown out and knee-deep in water, Beatrice’s heart had almost failed her, not knowing how her friends had fared exposed to the nearer shock of the dread explosion. Had they perished, her plight and that of poor Jeannette, whom she bore in her arms, would have been mournful indeed. Burning with a desire to see the last of the passage which had almost become their tomb, Edgar lifted Jeannette without a word, grasped Beatrice by the hand, and stumbled back along the tunnel, Peter going on ahead. A faint light could be seen gleaming in the distance, and full of hope that the way lay open to the sky, they pressed on faster and faster. Two-thirds of the length of the passage had been traversed when they encountered great heaps of fallen earth and masonry, over the top of which the gleam of daylight dimly struggled. Crawling and scrambling on all-fours as best they could, they made their way onward still, until at last they emerged into the open air in the midst of a great pit torn in the earth by the force of the explosion. The air was still sultry with the heat of the fires, burning embers and blackened branches lay strewn about in all directions, and a thin veil of smoke lay over all. But not a sign of life was there, save upon the walls of the castle, where one or two figures could be seen peeping fearfully over the battlements.