Instantly there was a trembling through t whole length of the projectile. Would it move? Would it leave the earth and go to Mars?
There was a moment of hesitancy, as if the great machine had not quite decided.
Then came a more violent vibration. There was a humming, throbbing, hissing sound. Suddenly the boys, and all within the projectile, felt it swaying. A moment later it began to shoot through space like a great rocket.
"Hurrah!" cried Jack. "We're off!"
"Yes," added Mr. Roumann joyfully, "we are on our way to Mars!" and he grasped the steering wheel and peered through the thick plate–glass windows of the pilot house into the vast space before them.
CHAPTER XV
SOMETHING ABOUT MARS
"Are we really in motion?" asked Jack, after a moment's silence. "It doesn't seem so."
"We are certainly in motion," declared Mr. Roumann. "See this dial?"
He pointed to one near the steering wheel. The hand on it was gently vibrating between some of the figures.