are inch of the sector. If we lose one life, we
will have failed. Move out!"

With Strong, Kit, Howard, Walters, and other officers of the Solar Guard
in the lead, the grim lines of men separated into smaller groups and
started their march through the deserted city. The swirling gas already
was down to within a hundred feet of the street level. When it dropped
to the surface, each man knew there would be little hope for anyone
remaining alive without oxygen masks.

Every room of every house and building was searched, as over all, the
deadly swirling gas dropped lower and lower and the pressure of the
oxygen was dissipated.

Once, Strong broke open the door to a cheap rooming house and raced
through it searching each room. He found no one, but something made him
go back through the first-floor rooms again. Under a bed in a room at
the end of the hall he found a young boy huddled with his dog, wide-eyed
with fear. Such incidents were repeated over and over as the searchers
came upon sleeping miners, sick mothers and children, elderly couples
that were unable to move. Each time they were taken outside to a jet car
where masks were strapped over their faces, and then driven to the
spaceport. And, all the while, the deadly methane ammonia gas dropped
lower and lower until it was within ten feet of the ground.

There were only a few buildings left to search now. The lines of the men
had reached the open grassy areas surrounding the city proper, and as
they collected in groups and exchanged information, Walters gathered
them together.

"You've done a fine job, all of you," he said. "I don't think there's a
living thing left in this entire sector. All volunteers and the first
four squads of enlisted guardsmen and second detachment of Space Marines
return to the spaceport and prepare to abandon Titan. Give all the aid
to the officer in charge that you can. Again, I want to thank you for
your help."

As the group of men broke up and began drifting away, Walters hurried
over to Strong and Kit Barnard. "Steve," he said, "I want you to
supervise the evacuation at the spaceport. Since this screen has blown
up, those poor people are frightened out of their wits. And they have a
right to be. If a major screen blew instead of a small one, we really
would be in trouble."

"Very well, sir," replied Strong. "Come on, Kit, you might as well blast
off with a load of children."

"Sure thing."

"Just a minute," Walters interrupted.