"I hardly think so. The projectile itself might not be harmed, as it is very strong, but the machinery and motors would probably be damaged." "Then what can we do?" "The only thing left for us to do is to escape." "Escape? You mean leave the projectile?" asked Mr. Henderson. "No, I mean escape in the Annihilator. There is no reason why we should stay here any longer. We have what we came to seek, and though I should like to make some further scientific observations, we will have to forego them. We will start the atmospheric motor, and leave Mars." "That's the stuff!" cried Jack. "Back to earth for ours! It's nice up here, when you don't do something they don't like, but the earth is good enough for me!" "That's what I say," added Mark. The Martians were hurrying their preparations to blow up the projectile. Perhaps they guessed that they must act promptly, or they may have had an intimation that something was going to happen, when the ports of the electric cannons were closed. The shutter of the observation tower was sealed, all openings were well fastened, and, just as the mine was completed and the explosive was about to be put in, Mr. Roumann started the atmospheric motor, and the projectile left Mars with a rush. Of course, the travelers could not see the blank looks of astonishment on the great faces of the Martians, but they could imagine them, as they shot away from the queer little planet at the rate of sixty miles a second. "Well," remarked Mr. Roumann as he went to the pilot house, after seeing that the motor was working well, "we got to the place we set out for, and we secured some Cardite, which is what I wanted. I am now able to repay you for building this projectile, Professor Henderson, you need never worry about money again." "I'm glad of it, as I shall devote the remainder of my life to science, and I may write a book about Mars." "Well, ob all de transmigatoriousness dat I eber seed," exclaimed Washington, "de continual exteriorosity ob de inhabitants ob dat planetary sphere am de mostest indisputatious!" Though what he meant by that no one knew. But it seemed to give the colored man great satisfaction. In due time they passed beyond the limits of the atmosphere of Mars, and again were sailing through space, the Etherium motor doing good work. Mr. Roumann tried some Cardite in it, and their speed was increased by half, so they reached the atmosphere of the earth in much shorter time than they calculated. They met with no mishaps, though they narrowly escaped collision with a great meteorite that was rushing through space, white hot. "Well, in a few days we will be at home," remarked Mr. Roumann one night, as he set the atmospheric motor in operation. "And I must say I have greatly enjoyed the trip." "So have I," admitted Jack, and Mark agreed with him.