y.

They were hard to find. Many of them were dead, victims of the purge.
The others were in hiding and word of them was difficult to get.

But slowly, one by one, they were ferreted out, the plan explained to
them, and then, by means of the tele-transport, they were brought to the
_Invincible_.

Hour after hour men worked, stripped to their waists, in the glaring
inferno of terrible force fields, fashioning new television units. As
fast as the sets were constructed, they were placed in operation.

The work went faster than could be expected, yet it was maddeningly
slow.

For with the passing of each hour, Stutsman clamped tighter his iron
grip on the planets. Concentration camps were filled to overflowing.
Buildings were bombed and burned. Murders and executions were becoming
too common to be news.

Then suddenly there was a new development.

"Greg, Craven has found something!" Russ cried. "I can't get him!"

Supervising the installation of a new televisor set, Greg spun around.
"What's that?"

"Craven! I can't reach him. He's blocking me out!"

Greg helped, but the apparatus was unable to enter the Interplanetary
building in New York. Certain other portions of the city adjacent to the
building also were blanketed out. In all the Solar System, the
Interplanetary building was the only place they could not enter, except
the Sun itself.

Craven had developed a field from which their field shied off. The
televisor seemed to roll off it like a drop of mercury. That definitely
ended all spying on Craven and Chambers.

Russ mopped his brow, sucked at his dead pipe.

"Light penetrates it," he said. "Matter penetrates it, electricity, all
ordinary forces. But this field won't. It's ... well, whatever Craven
has is similarly dissimilar. The same thing of opposite nature. It
repels our field, but doesn't affect anything else. That means he has
analyzed our fields. We have Wilson to thank for this."

Greg nodded gravely. "There's just one thing to be thankful for," he
declared. "He probably isn't any nearer our energy than he was before.
But now we can't watch him. And that field of his shows that he has
tremendous power of some sort."

"We can't watch him, but we can follow him," corrected Russ. "He can't
shake us. None of them can. The mechanical shadow will take care of
that. I have one for Craven with a bit of 'bait' off his spectacles and
he'll keep those spectacles, never fear. He's blind as a bat without