"Permission denied!" said Walters. "This is exactly what I've been talking about, Steve. You want to leave to go to Mars and look for Tom when we need you here on the project."

Strong's face suddenly turned white. And then, for the first time in his career, he ignored military courtesy and turned to leave without the courtesy of a salute or permission to do so. Connel almost called him back, but Commander Walters put a restraining hand on the major's arm.

"Think of it this way, Lou," he said. "If you wanted something you believed to be right, and it was denied you, how would you feel?"

"I'd very likely do the same thing," snapped the major. "And I'd get my rockets busted for it by my commanding officer!"

Walters grinned and pulled the major back to the desk where they continued their discussion of the receivers on Mars.

They had no sooner begun their discussion when the sliding door opened and Professor Hemmingwell burst into the room, his smock flying behind him, his hair ruffled and eyes wide with fright.

"The ship! The ship!" he cried out. "Someone has blown up the whole control panel of the ship!"