d jumble of questioning thoughts as I came up, and
took command of the situation promptly. It will be understood, of
course, that in those days men had not learned to blank their minds
against the menore, as they do to-day. It took generations of training
to perfect that ability.

"Open the exit," I ordered Kincaide, who was standing by the switch, key
in the lock.

"Yes, sir," he thought promptly, and unlocking the switch, released the
lever.

The great circular door revolved swiftly, backing slowly on its fine
threads, gripped by the massive gimbals which, as at last the ponderous
plug of metal freed itself from its threads, swung the circular door
aside, like the door of a vault.

* * * * *

Fresh clean air swept in, and we breathed, it gratefully. Science can
revitalize air, take out impurities and replace used-up constituents,
but if cannot give it the freshness of pure natural air. Even the
science of to-day.

"Mr. Kincaide, you will stand by with five men. Under no circumstances
are you to leave your post until ordered to do so. No rescue parties,
under any circumstances, are to be sent out unless you have those orders
directly from me. Should any untoward thing happen to this party, you
will instantly reseal this exit, reporting at the same time to Mr.
Correy, who has his orders. You will not attempt to rescue us, but will
return to the Base and report in full, with Mr. Correy in command. Is
that clear?"

"Perfectly," came back his response instantly; but I could sense the
rebellion in his mind. Kincaid and I were old friends, as well as fellow
officers.

I smiled at him reassuringly, and directed my orders to the waiting men.

"You are aware of the fate of the two ships of the Patrol that have
already landed here," I thought slowly, to be sure they understood
perfectly. "What fate overtook them, I do not know. That is what we are
here to determine."

"It is obvious that this is a dangerous mission. I'm ordering none of
you to go. Any man who wishes to be relieved from landing duty may
remain inside the ship, and may feel it no reproach. Those who do go
should be constantly on the alert, and keep in formation; the usual
column of twos. Be very careful, when stepping out of the ship, to
adjust your stride to the lessened gravity of this small world. Watch
this point!" I turned to Dival, motioned him to fall in at my side.
Without a backward glance, we marched out of th