Questioning Hankos, the professor learned how to reach the strange place. It was in the midst of a desolate country where none of the giants ever went, so afraid were they of the strange phenomenon. It was a week’s journey. Sometimes the _Mermaid_ flew through the air, and again it sailed on vast lakes or inland seas. On the trip they met with big waterfalls and terrible geysers that spouted a mile or more into the air. They traveled by night as well as day, though it was necessary to keep a sharp watch. Sometimes the ship passed through great flocks of birds that surrounded her and sought to pierce the aluminum hull with their sharp beaks and talons. Over the mountains and valleys the ship sailed until, one evening, there sounded through the air a strange rumbling sound. “It is thunder,” said Old Andy. “It is the water column,” replied the scientist. “We are at the end of our trip. May the remainder be as successful!” The ship was lowered to the surface, as it was deemed best to approach the column when the lights were shining. No one slept much that night, for the roaring and rumbling never ceased. In the morning the ship was sent forward slowly. Ever and ever the terrific sound increased, until it was almost deafening. They had to call to each other to be heard. Then, as the _Mermaid_ passed over a mountain, the adventurers saw, in a valley below them, the up-shooting water. It was a vast column, nearly three hundred feet in thickness, and as solid and white as a shaft _of_ marble. Up, up, up, it went, until it was lost to sight, but there were no falling drops, and not even a spray came from the watery shafts. “There is a terrible power to it,” the professor said. “May it prove our salvation!” The ship was lowered about a hundred feet away from the waterspout. All around them the ground was vibrating with the force of the fluid. “To think that connects with the world above!” exclaimed Jack. “It’s a good thing for us that it does,” Mark answered. “We must lose no time,” the professor put in. “If the earthquake destroyed the downward shaft, it may effect this one in time. We must escape while we can.” Then, for the first time, he opened the storeroom and the big cylinder was disclosed to view. It was made of aluminum, and shaped like an immense cigar. The hull was double, and it was strongly braced. Inside were padded berths for the occupants, and there was just room enough for the seven adventurers. Once they had entered they could not move about, but must stay in their little compartment. Compressed air in strong cylinders furnished a means of breathing, and there were tiny electric lights operated by a storage battery. There was also a chamber to be filled with the lifting gas. The cylinder was so arranged that it would float on it’s long axis if thrown into the water. A trap door hermetically sealed gave access to the interior. A small propellor, worked by compressed air, furnished motive power.