was to escape outside.

He ran wildly on, hoping to reach an outer door. But he seemed now to be
in a maze, for nothing was familiar to him. He could no longer remember
how many times he had run into groups of Plutonians, nor could he guess
how many followed on his heels.

Then he stumbled into a small, round chamber out of which led three
tunnels. As he looked around quickly to select his next means of escape,
barking Plutonians erupted from each opening. Burl backed up against the
wall, knowing that this time he was trapped.

A blaze of sparks broke over his head as a blast banged across the
room. The red-eyed, scrabbling figures charged, their chinless mouths
opening to emit barking calls of bestial anger. One aimed a rodlike
contrivance at him, and there was another flare of light.

The room dissolved around him in a glare of brilliant green. As he
slipped helplessly to the floor, he lost consciousness.

Chapter 18. _Sacrifice on the Sacred Moon_

"Burl Denning! Can you hear me, Burl Denning?" A thin, tinny voice
somewhere was calling him. But the darkness was all around, and Burl
felt a great sleepiness and a desire only to sink deeper into the
cottony nothing in which he seemed to be cradled.

"Burl Denning! If you can hear me, speak up!" Again the faint, scratchy
voice nagged at Burl's mind. He really ought to answer. He tried to open
his mouth. Something hard and cold was pressing against his back. He
tossed and squirmed.

Once more the voice called, and this time he decided that he must be
asleep. He struggled to open his eyes, then finally blinked them wide in
an effort to adjust himself to his surroundings.

He was apparently out in the open, and it was night. The sky was dark,
not black, but almost so--a deep, blue-black. There was a pale blue
saucer hanging in the sky. It blotted out most of the view. Gradually,
he became aware of a shiny barrier between him and that sky--he was not
out of doors. Something like a glass dome seemed to be overhead.

Burl raised his head. There was no one in sight. He felt dizzy and
confused. He lifted a hand to his brow, and felt the cold glass of his
space helmet. He was still wearing his space suit then. The voice--it
must be in his helmet phone.

"Hello," he ventured weakly. "Who's calling?"

Quickly the faint voice replied, growing stronger. "Burl, are you all
right? Where are you?"

Burl looked around. He was sitting on the floor of an isolated enc