stupid cadets, you're just wasting my time. There's plenty
of work to do and precious little time to do it in." He turned to
Barret. "Come on, Dave, let's get this mess cleared away."

"Yes, sir," said Dave Barret.

As Hemmingwell and Barret turned their attention to the wrecked control
panel, Connel, Walters, and Strong climbed out of the ship and left the
hangar. On the slidewalk, headed back to the Academy, Commander Walters
looked at Connel inquiringly.

"What now, Lou?" he asked.

"I have an idea, Commander," said Connel. "I'm going to spend the rest
of the night listening to this audiotape over again. Then I'm going to
do a little digging around."

"All right," said Walters. "And I suppose you'll want to talk to Manning
and Astro when they get back."

Connel looked at Captain Strong grimly. "I want to talk to them so
badly, I would crawl on my hands and knees to get to them right now."

Strong flushed angrily but said nothing, and as soon as the three
officers arrived at the Academy grounds, he excused himself. He walked
slowly and thoughtfully along, looking at the dormitories with unseeing
eyes and hearing with deaf ears the noise of the cadets getting ready
for bed. He could not believe that Roger or Astro had abandoned their
posts, or that Tom would run off to disappear on Mars, just for the sake
of disappearing. In all his years at the Academy, Strong had never met
three boys who so exemplified the true spirit of Space Cadets. Something
was wrong somewhere. But what?

Strong paused outside the huge recreation hall, watching the cadets.
Tony Richards and the _Capella_ unit walked by, and returning their
salutes, Strong could only see Tom, Roger, and Astro.

A figure dressed in the black-and-gold uniform of an officer in the
Solar Guard walked toward him. Strong's eyes lighted up with
recognition.

"Joan!" he exclaimed. "What are you doing here?"

"Looking for you," she said. She had some papers in her hand and held
them out to him.

"What's this?" he asked, glancing at them in the light reflected from
the hall, and then back to the serious face of the brilliant young
physicist, Dr. Joan Dale, who, in spite of being a woman, had been
placed in charge of the Academy laboratories, the largest and most
complete in the entire Solar Alliance.

"Steve," she began, "I was in charge of the psychograph tests taken of
all the workers at the projectile operation after the first mishap--"

"How did you kn