ay. A score of men leaped
through the gap before the dust had settled. Morey beamed them down
mercilessly before they could fire their weapons.

"In the air, quick!" Arcot yelled. He turned on his power suit and rose
into the air, signalling Torlos to grab his ankles as he had done
before. Morey slammed another parting shot toward the doorway as he
lifted himself toward the ceiling. Then both Earthmen snapped on their
invisibility units. Torlos, because of his direct contact with Arcot,
also vanished from sight.

More of the courageous, but foolhardy Satorians leaped through the
opening and stared in bewilderment as they saw no one moving. Arcot,
Morey, and Torlos were hanging invisible in the air above them.

Just then, the shining bulk of the _Ancient Mariner_ drifted into view.
They drew back behind the wall and sought shelter. One of them began to
fire his compressed air gun at it with absolutely no effect; the heavy
lux walls might as well have been hit by a mosquito.

As the airlock swung open, Arcot and Morey headed out through the breach
in the wall. A moment later, they were inside the ship. The heavy door
hissed closed behind them as they settled to the floor.

"I'll take the controls," Arcot said. "Morey, head for the rear; you
take the moleculars and take Torlos with you to handle the heat beam."
He turned and ran toward the control room, where Wade and Fuller were
waiting. "Wade, take the forward molecular beams; Fuller, you handle the
heat projector."

Arcot strapped himself into the control chair.

Suddenly, there was a terrific explosion, and the titanic mass of the
ship was rocked by the detonation of a bomb one of the men in the
building had fired at the ship.

Torlos had evidently understood the operation of the heat beam projector
quickly; the stabbing beam reached out, and the great tower, from floor
to roof, suddenly leaned over and slumped as the entire side of the
building was converted into a mass of glowing stone and molten steel.
Then it crashed heavily to the ground a half mile below.

But already there were forty of the great battleships rising to meet
them.

"I think we'd better get moving," Arcot said. "We can't let a magnetic
ray touch us now; it would kill Torlos. I'm going to cut in the
invisibility units, so don't use the heat beams whatever you do!"

Arcot snapped the ship into invisibility and darted to one side. The
enemy ships suddenly halted in their wild rush and loo