The humming in the engine room started up, rose and fell uneasily a
couple of times, and then they felt a surge of force. Lockhart fell
gently to the floor as the ship began to drive ahead, and then in a few
minutes the A-G drive was back on, and the _Magellan_ was again under
control.

"We took what they had to give, and it wasn't enough," exulted Haines.
"Now wait till we reach their main works. We'll show them!"

Lockhart shook his head wearily as he and Russ worked over the controls.
"Let's hope we don't have to show them soon. Our ship is running on
emergency rigging. Caton says he's going to have to rest the ship and
rewire a good part of the system. Meanwhile, we will be able to reach
Pluto safely enough."

Pluto was visible in the forward viewplates. They could see lighter and
darker patches on it, almost like the markings of continents and oceans,
but there was no evidence of an atmosphere, nor had they expected any.

Readings showed that the average surface temperature was about 200 deg.
Fahrenheit below zero, even lower in many places. They searched the
surface for signs of their foe.

They found what they wanted on the north polar depression, a basin in
the oblate sphere of Pluto. There was no ringed station. There rose a
vast pile of dark masonry--a mighty structure covering at least a square
mile, a fortress building whose roofs bristled with an array of masts
and reflectors. And hanging on patrol over this polar basin were two
more of the dumbbell ships.

"We're in no position to come to grips with them," said Lockhart. "I'm
going to take the _Magellan_ into a low orbit around Pluto's equator.
We'll be out of their sight, yet near enough to do some probing and
exploring while we're making repairs."

This they proceeded to do, swinging the ship down to within a few
hundred miles of the Plutonian surface, setting on a fixed orbit around
the equator, exactly as the sputniks of years past had first circled the
bulk of the Earth. Staying far enough up to maintain orbit, they were
close enough to be below the planet's radiation belt.

Taking stock of the ship's condition showed that they dearly needed this
delay. Repairs would not be completed for several days. Practically
everyone had been bruised or shaken up; Oberfield had a fractured skull
and was in serious condition; Ferrati had broken his leg and pelvis;
Shea had a couple of cracked ribs. The men were given emergency medical
treatment and co