n the wall.

"But just as the big fellow was about to cook me for good and all," he
concluded, "something happened to the current, and to the gravity at
the same time--"

"That was when I pulled the lever in the dome building!" exclaimed
Brand.

He told of what had befallen him in the Rogan power-house. "That
lever, Dex!" he said swiftly. "It's the keynote of the whole business.
It absolutely controls the pull of gravity, and Lord knows what else
besides. If we could only get at it again! Perhaps we could not only
shut it off so that Jupiter's pull would function again, but also
reverse the process so its gravity would be _increased_! Think what
that would mean! Every Rogan in the red empire stretched out and
immovable, possibly crushed in by his own weight!"

"It's a wonderful thought," sighed Dex; while Greca's eyes glowed with
a sudden hope for her enslaved race, "but I don't see how we could
ever--"

He stopped; and glanced in alarm down the passage behind them. Greca
and Brand, hearing the same soft noise, whirled to look, too.

* * * * *

Far down the passage, just sneaking around the bend, was a group of
Rogan guards, each armed with a death-tube.

"Back to the pen!" cried Brand.

He slid the bolt, and jerked the door open. They rushed into the
walled enclosure again, the slamming of the door behind them cutting
off the enraged squeals of the Rogans.

"This isn't going to mean anything but a short delay, I'm afraid,"
said Brand, clenching his fists in an agony of futility. "They'll be
in here in a minute, and get us like trapped rats."

"Not before we get a lot of them," said Dex grimly.

"But that isn't enough, man! We don't want to die, no matter how
decently we do it. We've won free, and stayed free this long; now,
somehow, we've got to reach our ship and get back to Earth to warn
them of the danger that hides here for our planet!"

He strode tensely up and down, smacking his fist into his palm. "The
lever!" he exclaimed. "That lever! It's our only answer! If we could
get to it.... But how can we? We couldn't break into the dome, now the
Rogans are on the watch for us, with anything less than a charge of
explosives. Or a tank. God, how I'd like to have an old-fashioned,
fifty-ton army tank here now!"

Greca exclaimed aloud as Brand's fleeting mental picture of one of
Earth's unwieldy, long-discarded war tanks registered on her brain.

"There is the great beast