or his
body.

Stuffing the heavy pipe in his tunic, Tom dropped into the unit and
opened the outside hatch. A blast of cool air struck him. The sun was
setting and the cadet knew that soon the near-zero temperatures of night
would settle over the desert. Tom poked his head out and the air stream
hit him like a solid wall. He looked back past the spinning wheels and
saw a long stretch of deserted road bordering a canal. His view forward
was blocked by the overhanging cab of the truck. The small step up to
the cab was a foot away. Tom eased back into the compartment again and
sat back against the wall to consider his next move. He would have a
better chance of not being seen if he waited for darkness. On the other
hand, they might reach their destination before that and he would be
caught. Tom made up his mind quickly.

Moving back to the hatch, he eased himself through the opening. There
was a ticklish moment when he had to let go of the side of the
compartment and swing over on the step. He took a deep breath and
lurched forward.

[Illustration]

Behind him, the huge thick wheels spun over the road. A slip now would
mean instant, crushing death. His fingers reached for and grasped the
door handle. Seconds later, he stood balanced on the step, swaying in
the wind.

He dared a glance into the window of the cab, wondering why he had not
been noticed before. He saw Cag and Monty inside, Cag driving and Monty
asleep. The driver was on the opposite side from Tom, and Monty was
slumped against the door.

[Illustration]

Tom realized that if he opened the door, Monty would fall out and
probably be killed, but he had no choice. He reached up for the handle
and tested it gently before swinging down on it to make sure it would
open. It gave a little. Then bracing himself, he pulled hard.

The door swung open and Monty fell out, hitting the pavement and rolling
off into the sand to lie still. Tom paid no attention to him. With a
mighty effort, he swung into the cab and confronted a startled,
wild-eyed Cag.

"You!" cried Cag.

"Stop this crate, or so help me, I'll break your head!" Tom shouted,
brandishing the short length of pipe.

In reply, Cag suddenly swerved the big truck to one side of the road,
hoping to throw Tom out of the open door. Tom managed to grab hold just
in time. He swung back into the cab and struck out with the pipe.

Cag ducked and swung the heavy truck to the opposite side of the road,
trying