riend. Hawks stepped on the accelerator and the car shot away in a roar
of blasting jets.

Tom and Captain Strong watched the car disappear and then turned back to
the shack. Each felt the same emotion, an unspoken determination to see
that Wallace and Simms paid dearly for causing the accident.

Re-entering the shack, they began a careful examination of the shaft.
Strong played his emergency light down the sides, but the beam
penetrated only a short distance.

"We'll leave a note for the emergency crew," said Strong. "Our belt
communicators might not work so far underground."

"You're going down, sir?" asked Tom.

Strong nodded. "If necessary. Tie that valve on the end of the rope
Astro used and lower it into the shaft. If we can touch bottom with it,
we'll climb down and see what Wallace and Simms were after."

"Yes, sir," said Tom. He took the length of rope, tied the heavy metal
valve to the end, and began lowering it into the shaft. Strong continued
to play the light down the shaft until the valve disappeared into the
darkness.

"Rope's getting short, sir," warned Tom. "Only have about two hundred
feet left."

Strong glanced at the remaining coils of line on the floor. "I'll get
more from the _Polaris_, if we need it," he said. "How long was that
line to begin with?"

"It's a regulation space line, sir," said Tom. "Astro took it out of the
emergency locker. It's about twelve hundred feet."

By this time the line, hanging straight down the shaft, had become
increasingly heavy. Suddenly it grew slack.

"I think I've hit bottom, sir," cried the cadet. "But I can't pull the
valve back up again to make sure."

Strong grabbed the end of the line and helped the cadet pull it back up
a short distance. Then they dropped the line again and felt a distinct
slackening of weight.

"That's bottom all right," said Strong. "Take this end of the line, run
it out of the window on your right, and back through the one on your
left. Then make it fast."

"Yes, sir," said Tom. He jumped out of the window, trailing the rope
after him, and reappeared almost immediately through the other window to
tie a loop in the line. After checking the knot and testing the line by
throwing his full weight against it, Strong stripped off his jacket and
wrapped it about the line to prevent rope burns. Then, hooking the
emergency light on his belt, he stepped off into the shaft. Tom watched
his skipper lower himself until nothing but the