Jack and Mark were glad to get busy, and for several hours they labored in the engine-room, where the two scientists were toiling. As this rendered it unnecessary for Washington to be there, the colored man went to his kitchen, while Andy again made a vain search of the projectile, looking for the crazy man. Though Mr. Roumann had provided duplicates of the power plates for the Etherium motor, it was quite a task to take out the broken pieces and insert the new ones. "Can't you run the atmospheric motor while we're fixing this one?" asked Jack. "That would prevent us falling, I should think." "No, for the reason that there is no atmosphere for it to work on," declared Mr. Roumann. "But don't worry. We shall soon be under way again. We will be somewhat delayed in reaching Mars, that is all." They labored hard all the rest of that day and part of what corresponded to the night, though of course the daylight outside never ceased. Little of it could penetrate the projectile, however, for the big car was all sealed up, save for the observation window in the pilot house and one on the side. "There," announced Mr. Roumann, after inserting the last new plate. "I think we are all right." It had been nearly eighteen hours since the motor had so suddenly stopped. "Will you start it now?" asked Jack. "Yes. I wish you and Mark would go to the pilot house and turn on the power. Do it very slowly. Mr. Henderson and I will stay here and see how the motor behaves." It was an anxious moment when the power was turned on the repaired machinery, but, to the delight of all, the motor again began to give out the mysterious force. The projectile ceased to fall, and once more was hurled onward. "That's the stuff!" cried Jack, as he noted the needle of the indicator moving around, showing that they were again headed for Mars. Once more they were shooting through the ether. The wonderful motor worked even better with the new plates, and Mr. Roumann said they had increased their speed about twenty-five percent. "So we will soon make up for what we lost," he added. They were all tired that night, for the work of making the repairs had not been easy, and Andy had gone over the whole projectile many times, looking for the hidden insane man. "I don't believe he can be here," was Mr. Henderson's opinion. "He certainly is," declared Mr. Roumann, "and we shall have more trouble from him." "I hope not," ventured Professor Henderson. It was on the second day after the accident, when the Annihilator was speeding along, that Jack and Mark, who were in the pilot house with Mr. Roumann, noticed a peculiar trembling of one of the needles on a dial designed to indicate the nearness of heavenly bodies. "We're coming close to something," said Jack. "We certainly are," admitted the scientist, with an anxious look at the instrument. "Maybe it's Mars," suggested Mark. "No, it can't be that planet."