ow it works."

Silence descended on them again, in which each was lost in his own
thoughts.

How many hours had passed, the Earthmen did not know. They had spent
the time in fruitless planning to escape from their tower room and go
back to the ship again. Though how they could get away in the ship
when the Rogans seemed able to propel it where-ever they wished
against the utmost power of their motor, they did not attempt to
consider.

One of Jupiter's short nights had passed, however--a night weirdly
made as light as day by red glares from the plates, which seemed to
store up sunlight, among their other functions--and the tiny sun had
risen to slant into their window at a sharp angle.

Suddenly they heard the familiar drawing of the great bolts outside
their door. It was opened, and a dozen or more of the Rogans came in,
with Greca cowering piteously in their midst and attempting to
communicate her distress to Brand.

* * * * *

At the head of the little band of Rogans was one the prisoners had not
seen before. He was of great height, fully two feet taller than the
others; and he carried himself with an air that proclaimed his
importance.

The tall one turned to Greca and addressed a few high-pitched, squeaky
words to her. She shook her head; whereupon, at a hissed command, two
of the Rogans caught her by the wrists and dragged her forward.

"They have come to question you," Greca lamented to Brand. "And they
want to do it through me. But I will not! I will not!"

Brand smiled at her though his lips were pale.

"You are powerless to struggle," he said. "Do as they ask. You cannot
help us by refusing, and, in any case, I can promise that they won't
learn anything from us."

The tall Rogan teetered up to the prisoners on his gangling legs, and
stared icily at them. Crouched beside him, her lovely body all one
mute appeal to the Earthmen to forgive her for the part she was forced
to play, was Greca.

At length the Rogan leader spoke. He addressed his sibilant words to
Greca, though his stony eyes were kept intently on the Earthmen.

"He says," exclaimed Greca telepathically, "to inform you first that
he is head of all the Rogan race on this globe, and that all on this
globe must do as he commands."

Brand nodded to show he understood the message.

"He says he is going to ask you a few questions, and that you are to
answer truthfully if you value your lives:"

"First, he