and winds and frost. Earth's scars wore away
through millions of years. We don't even know where the wounds were! But
there were people in those days!

"And they were civilized," continued Soames. "They had superconductors
and one-way conductors of heat. They had reached the point where they
didn't need fire any more, and they built ships of magnesium alloy. They
saw the Fifth Planet when it flew apart. They knew what must happen to
Earth with the whole solar system filled with a planet's debris. Earth
would be smashed; wrecked; depopulated, made like the moon is now! Maybe
they had ships that went to other planets, but not enough to carry all
the race. And the only other planets they could use were the inner ones,
and they'd be smashed like the Earth and moon? What could they do? There
might be one or two survivors here and there, bound to lapse into
savagery because they were so few. But where could the civilized race
go?"

Gail made an inarticulate sound.

"They might," said Soames in a flat voice, "they might try to go into
the future; into the time beyond the catastrophe, when Earth would have
healed its wounds. They might send someone ahead to see if it were
possible. Yet if they sent one ship first--with everyone left behind
doomed to die--if they sent one ship first, it's reasonable that they'd
give children the chance of survival. It's even reasonable that they'd
send two boys and two girls...."

"They--had a transmitter," Gail said, as if breathing hurt her. "You
destroyed it. They meant to signal, not for help as we thought, but for
their people to join them. M-maybe now they're hoping to get the
material and the power to build another transmitter. Since everything
they use is so simple, the boys might have been taught how. They were
taught to repair the one they had! They did repair it! Maybe they can
make one, and hope we'll help them! They'd have been especially
trained...."

"Nice, isn't it?" asked Soames. "They were sent here in some fashion to
make a beachhead for the landing of their people. A civilization that's
starkly, simply doomed unless it can migrate. No mere conquest, with
tribute to be paid to it. It has to take over a whole planet! It has to
take over Earth, or die!" He winced. "And the kids, now, think of their
parents as waiting for mountains to fall upon them from the sky, and
I've doomed them to keep on waiting. Now the kids must be hoping
desperately that they can get us to give t