It seemed like a month later, though, of course, it could have been only a few hours or a day at most when Jack opened his eyes. He saw his companions, white and senseless all around him, and at first thought they were dead. Then he saw Mark looking at him, and Washington asked: “Is any one livin’ 'sides me?” “I am,” replied Jack decidedly. Then, one after another they regained their senses. But they were in a strange daze, for they were being carried along like a shooting star, only, as they went at the same rate as did the element carrying them, they did not _realize_ this. “I think I’m hungry,” said Bill, who had the best appetite of any of the travelers. “You’ll find a beef capsule in the little compartment over your head,” spoke the professor. Bill was about to reach for it, when they were all startled by a sudden side motion of the cylinder. Then came a violent shock, and a sound as of splashing water. Next the cylinder seemed to be falling, and, a few minutes later to be shooting upward. Following this there was another splash and the cylinder began to bob about like a cork on a mill pond. “We have reached the sea! We are afloat on the ocean!” cried the professor. Hurriedly he disengaged himself from the straps that held him to his bunk. He pushed back the lever that opened the manhole. Into the opening glowed the glorious sunlight, while to the occupants came the breath of salt air. “Hurrah!” cried Jack. “We are safe at last!” “Safe at last!” the professor answered, and then they all gave a cheer. For their cylinder, which might now be termed a boat, was floating on the great Atlantic. The blue sky was overhead and the air of the sea fanned their cheeks. They had shot up from the underground earth, in the column of water, had been tossed high into the air, had fallen back when the liquid shaft broke into spray, had descended into the ocean, gone down a hundred feet or more, and then had shot up like a cork to bob about the surface. For a week they were afloat, and then they were picked up by a passing vessel, rather weak and very much cramped, but otherwise in good shape. They said nothing of their adventures, save to explain that they were experimenting in a new kind of boat. About a month later, for the ship that had rescued them was a slow sailer, they were back on the island whence that wonderful voyage was begun. * * * * * “Well, we solved the mystery of the center of the earth,” remarked Jack, one evening, when they were gathered in the old shack where so many wonderful adventures had been planned. “Yes, we did,” said Mr. Henderson. “And no one else is ever likely to go there.” “Why?” “Because the only way of getting there was destroyed by the earthquake, and no one could ever force his way down through that upward-shooting column of water.” “That’s so. Well, we have the diamonds, anyway,” spoke Mark. “They ought to make us rich.”