The Invincible's speed was slacking off, slower and slower, until it barely crawled in comparison to its former speed.

Slowly they circled Jupiter's great girth, staring out of the vision port for a sight of Craven's ship. They were nearing the position the little mechanical shadow had indicated.

"There it is,” said Russ suddenly, almost breathlessly.

Far out in space, tiny, almost like a dust mote against the great bulk of the monster planet, rode a tiny light. Slowly the Invincible crawled inward. The mote of light became a gleaming silver ship, a mighty ship-one that was fully as large as the Invincible!

"That's it all right,” said Greg. “They're lying behind a log out here raising hell with our television apparatus. Maybe we better tickle them a little bit and see what they have."

Rising from the control board, he went to another control panel. Russ remained standing in front of the vision plate, staring down at the ship out in space.

Behind him came a shrill howl from the power plant. The Invincible staggered slightly. A beam of deep indigo lashed across space, a finger suddenly jabbing at the other ship.

Space was suddenly colored, for thousands of miles, as the beam struck Craven's ship and seemed to explode in a blast of dazzling indigo light. The ship reeled under the impact of the blow, reeled and weaved in space as the beam struck it and delivered to it the mighty power of the screaming engines back in the engine room.

"What happened?” Greg screamed above the roar.

Russ shrugged his shoulders. “You jarred him a little. Pushed him through space for several hundred miles. Made him know something had hit him, but it didn't seem to do any damage."