ay
that you secure the Hot Rod power switch so that it cannot be turned
on without my personal authorization?"

"Sure, captain, I can--"

The captain interrupted. "Mr. Blackhawk, I should prefer that you not
tell me or anyone else aboard the method you will use; and that you
make your method as difficult as possible to discover. This I shall
leave," he added dryly, "to your rather ... fertile ... imagination.

"There is reason to believe that Project Hot Rod was turned on by a
saboteur. Your method must be proof against him, and if he exists, he
will not be stupid." The captain switched off.

Mike turned to the control panel, and after a few minutes thought
busied himself for some time.

Then he headed for the bridge where Dr. Johnston, Chauvenseer, and the
captain had dismissed the others and were utilizing every check that
Dr. Johnston could dream up to assure themselves that Hot Rod was
actually turned off and would remain secure at least for the duration
of the flare; and trying as well to find out just what form the
sabotage had taken.

Without interrupting the others, Mike seated himself at the subsidiary
post at the computer's console on Bessie's right, and got her to brief
him while he examined the close-up display of Hot Rod.

After a few minutes he reached over and increased the magnification to
its maximum, showing only a small portion of the balloon, then moved
the focus to display the control room entrance as well as part of the
anchor tube and the cable between the two.

"I think I've found your saboteur, sir," he said.

The captain was at his side almost instantly. "Where is he?" he asked
briefly.

"Not he, sir. It. And I'm not sure just where--but look. Hot Rod's
cable is taut. There's thrust on the balloon. That probably means a
puncture and escaping nitrogen.

"I think," he said, "that the saboteur may have been a meteor that
punctured the balloon, and the nitrogen escaping through the hole it
made is now producing enough thrust to keep that cable taut. Though,"
he added thoughtfully, "I don't see why the servos couldn't maintain
the beam to Thule--though obviously, they couldn't."

"How dangerous is such a puncture?" asked the captain. "How seriously
would Hot Rod be damaged? How soon must it be repaired?"

"The puncture itself shouldn't be too dangerous. Even if all the
nitrogen's gone, the balloon's in a vacuum and won't collapse--and
that's about the only serious effect a puncture