It was hard work, but this they did not mind. The finding of the treasure meant to them a lifetime of leisure, had they a mind to take it. At last the bags were full and still more of the gold remained. "We will pile it on the floor of the diving bell," signed Amos Fearless. "Let us make one trip of it. After this I never wish to visit the bottom of the sea again." Both worked steadily, and in half an hour had every piece of gold in sight picked up. They were just taking the last of the gold to the diving bell when a horrible roar broke upon their ears. The demons of the deep were returning to the locality. "Quick!" cried Dave. "Or it will be all up with us!" Father and son ran for the diving bell. But now the demons saw them and the roar increased. Soon fully fifty of the ferocious creatures were leaping and swimming toward the mound. Their sharp teeth clicked together as if anxious to bury themselves in the bodies of the human beings. With all haste Amos Fearless and Dave got into the diving bell. But before they could close the door one of the demons was upon them. He caught the old diver by the head, intending to pull that member from the rest of the body. Dave's heart leaped into his throat, yet his presence of mind did not desert him. Raising one of the submarine guns he blazed away and caught the monster of the deep straight in the mouth and throat. Mortally wounded, the demon fell back, one arm still within the doorway of the diving bell. As quickly as possible Amos Fearless turned and shoved the arm outside. Dave was about to close the door when his father motioned him to desist. Then the old diver caught up one of the torpedoes which had been brought along, set its clock-like movements in motion, and hurled it forth among the approaching company of demons. It fell in their midst, and, attracted by the shining metallic covering of the torpedo, all crowded around the object. As they did this, the door of the diving bell was closed and the signal was sent up to hoist away immediately. Hardly had the diving bell begun to move when a fearful shock made it quiver from top to bottom and cracked one of the glass sides. The torpedo had exploded, dealing death and destruction among the demons of the deep, impossible to describe. Fully a score of the monsters were utterly annihilated, while nearly every one of the others was badly wounded. One that escaped came after the diving bell, trying vainly to destroy the bell and those inside. But an unlucky movement caused the demon to come in contact with one of the crab-like claws of the bell, and seeing this, Dave worked the claw instantly, thus making the demon a prisoner. The creature flopped violently, but as the bell ascended to the upper waters of the ocean, it seemed to become stunned, and before the surface was gained it lay utterly helpless. Soon the diving bell was hoisted aboard of the _Swallow_.