Higher and higher into the air mounted the _Flying Mermaid_, while in the water below, the whale, incensed by missing his prey, was lashing the waves to foam. “Well, that was a narrow squeak; as close as I ever care to come to it!” exclaimed Andy as he let go of the steel rail to which he was clinging and entered the conning tower. “I had no idea of hitting the big fish.” “I guess he would have taken after us whether you had fired at him or not,” said Mr. Henderson. “He was probably looking for trouble, and took the first thing that came in his way, which happened to be us. Some whales are like that, so I have read; big bull creatures, exiled from the school to which they once belonged, they get like mad creatures and know neither friend nor foe. Something like rogue elephants, I imagine.” Now, having thus unexpectedly risen into the air, the professor decided to continue travel in that style for a while at least. It would require less force to propel the ship, and the going would be more comfortable, since in the upper regions the _Mermaid_ rode on an even keel, while in the water there was more or less rolling, due to the action of the waves. Once recovered from their fright caused by the whale, and having lost sight of the enormous creature, for they were now far above the ocean, the adventurers began to think of something to eat. Washington lost little time in preparing a meal, and it was eaten with a relish. The electric cooking stove worked to perfection, for the colored man had learned how to use that aboard the _Porpoise_ and _Monarch_, and could be depended on to turn out appetizing dishes. “What do you say to traveling through the air at night?” asked Mr. Henderson, as he arose from the table. “Suits me,” replied Mark. “There’s less danger than in the water, I think.” Bill, Tom and Washington arranged to stand the night watch, and, when the professor had examined the engines and given orders about keeping the ship on her course through the air, he retired to his bunk. Jack and Mark soon followed. It must have been about midnight when Mark was awakened by a movement that seemed to come from the storeroom next to where his sleeping place was located. At first he thought he had been dreaming, but, as he found he was wide awake, he knew it was no imagination that had affected him. “I certainly heard something,” he said to himself. “It sounded just as it did the other night. I wonder if I ought to investigate.” He thought over the matter carefully as he sat upright in his bunk in the darkness. True the noise might be a natural one, due to the vibration of the engine, or to some echo from the machinery. As Mark listened he heard it again. This time he realized it was the slow movement of some heavy body. He felt a cold shiver run over him and his hair evinced an uncomfortable tendency to stand upright. But he conquered his feelings and resolved to keep cool and see if he could discover what had awakened him.