He pulled toward him the main starting lever of the Cardite motor, while Professor Roumann opened the valve which admitted to the plates and cylinders the mysterious force that was to send them on their way. "Elevate the bow!" called Professor Henderson. "Elevated it is," answered the German, as he turned a wheel which directed the negative gravity force against the surface of the ground and tilted up the nose of the _Annihilator_, as a skyrocket is slanted in a trough before the fuse is ignited. "Throw over the switch," directed Mr. Henderson, and the other scientist, with a quick motion, snapped it into place, amid a shower of vicious electric sparks that hissed as when hot iron is thrust into water. "Steer straight ahead!" called Professor Henderson to Mark and Jack, who were in the pilot house. "We'll head for the moon later." "Straight ahead it is," answered Jack. There was a trembling to the great projectile. Up rose her sharp-pointed bow. She swayed slightly in the air. The trembling increased. The great Cardite motor hummed and throbbed. There was a crackling as from a wireless apparatus. Then, with a rush and a roar, the big steel car, resembling an enormous cigar, soared away from the earth, like some gigantic piece of fireworks, and shot toward the sky. "We're off!" shouted Mark. "For the moon!" added Jack. And the _Annihilator_ soared upward and onward, while those in her never dreamed of the fearful adventures that were to befall them ere they would again be headed toward the earth. CHAPTER XV THE SHANGHAI MAKES TROUBLE Remaining in the engine room long enough to see that all the motors and apparatus were working smoothly, Professor Henderson made his way to the pilot house forward, where Mark and Jack were in charge of the steering gears. The projectile could be started and stopped from there, as well as from the engine room, once the motor was set going. "Well, boys, how does it feel to be in space once more?" asked the scientist. "Fine," answered Mark. "But while I was shut up in that old house I feared I'd never have this chance again." "It seems like old times again, to be flying through space," remarked Jack. "My! but we aren't making half the speed of which the projectile is capable. Why, we're only going about twenty miles a second," and he spoke as if that was a mere nothing. "Twenty miles is some speed," observed Mark. "The earth goes around the sun at the rate of nineteen miles a second, or about seventy-five times as fast as the swiftest cannon-ball, so you see, Jack, you are 'going some,' as the boys say." "Yes, but we went much faster when we went to Mars. Still, no matter how fast we travel, you'd never realize it inside here."