"Heroic again, eh? But I took a compressed air bottle in the lock with
me. When the outer door was open, I opened the stopcock and shut the
door. The air bottle filled the lock behind me. Naturally I'd fasten the
door after I came out! One must be intelligent!"

Joe heard Brent muttering, "Yes, he'd do that!"

"Somebody check it!" snapped Joe. "Make sure! It might amuse him to
watch us die while he knew we could get back in if we were as smart as
he is."

There were clankings on the hull. Men moved, unfastening the lines which
held them to the hull to get freedom of movement, but not breaking the
links which bound them to each other. Joe saw Haney go grimly back to
the task of throwing away the stuff that they had brought out for the
purpose. Then Mike's voice, brittle and cagey: "Haney! Quit it!"

Sanford's voice again, horribly amused. "By all means! Don't throw away
our garbage! We may need it!"

A voice snapped, "This lock's fastened." Another voice: "And this...."
Other voices, with increasing desperation, verified that every airlock
was implacably sealed fast by the presence of air pressure inside the
lock itself.

Time was passing. Joe had never noticed, before, the minute noises of
the air pressure apparatus strapped to his back. His exhaled breath went
to a tiny pump that forced it through a hygroscopic filter which at once
extracted excess moisture and removed carbon dioxide. The same pump
carefully measured a volume of oxygen equal to the removed CO_2 and
added it to the air it released. The pump made very small sounds indeed,
and the valves were almost noiseless, but Joe could hear their
clickings.

Something burned him. He had been standing perfectly still while trying
to concentrate on a way out. Sunshine had shone uninterruptedly on one
side of his space suit for as long as five minutes. Despite the
insulation inside, that was too long. He turned quickly to expose
another part of himself to the sunlight. He knew abstractedly that the
metal underfoot would sear bare flesh that touched it. A few yards away,
in the shadow, the metal of the hull would be cold enough to freeze
hydrogen. But here it was fiercely hot. It would melt solder. It might--

Mike was fumbling tin cans out of the net bag from which Haney had been
throwing them away. He was a singular small figure, standing on shining
steel, looking at one tin can after another and impatiently putting them
aside.

He found one that seemed t