tening of one hard lineament, stared
around the air-room; making sure that no serious damage had been done to
the vital machinery of the air-purifier--the very lungs of the great
space-ship.

Dismounting the Standish, he lugged it back up to the main saloon,
replaced it in its safe and again set the combination lock. Thence to
the lifeboat, where Clio cried out in relief as she saw that he was
unhurt.

"Oh, Conway, I've been so afraid something would happen to you!" she
exclaimed, as he led her rapidly upward toward the control room. "Of
course you...." she paused.

"Sure," he replied, laconically. "Nothing to it. How do you feel--about
back to normal?"

"All right, I think, except for being scared to death and just about out
of control. I don't suppose that I'll be good for anything, but whatever
I can do, count me in on."

"Fine--you may be needed, at that. Everybody's out, apparently, except
those who, like me, had a warning and could hold their breath until they
got to their suits."

"But how did you know what it was? You can't see it, nor smell it, nor
anything."

"You inhaled a second before I did, and I saw your eyes. I've been in it
before--and when you see a man get a jolt of that stuff just once, you
never forget it. The engineers down below got it first, of course--it
must have wiped them out. Then we got it in the saloon. Your passing out
warned me, and luckily I had enough breath left to give the word. Quite
a few of the fellows up above should have had time to get away--we'll
see 'em all in the control room."

"I suppose that was why you revived me--in payment for so kindly warning
you of the gas attack?" The girl laughed; shaky, but game.

"Something like that, probably," he answered, lightly. "Here we are--now
we'll soon find out what's going to happen next."

In the control room they saw at least a dozen armored figures; not now
rushing about, but seated at their instruments, tense and ready.
Fortunate it was that Costigan--veteran of space as he was, though young
in years--had been down in the saloon; fortunate that he had been
familiar with that horrible outlawed gas; fortunate that he had had the
presence of mind enough and sheer physical stamina enough to send his
warning without allowing one paralyzing trace to enter his own lungs.
Captain Bradley, the men on watch, and several other officers in their
quarters or in the wardrooms--space-hardened veterans all--had obeyed
instantly and