estion about it. It was even easier than we'd thought.
We could simply bypass the cooling unit, letting the engine housings
stay open to the between-hulls section; then it was simply a matter of
cutting a small opening into that section at the other end of the ship
and installing a sliding section to regulate the amount of air flowing
in. The exhaust from the engine heat pumps was reversed, and run out
through a hole hastily knocked in the side of the wall.

Naturally, we let it flow too fast at first. Space is a vacuum, which
means it's a good insulator. We had to cut the air down to a trickle.
Then Wilcox ran into trouble because his engines wouldn't cool with
that amount of air. He went back to supervise a patched-up job of
splitting the coolers into sections, which took time. But after that,
we had it.

I went through the hatch with Muller and Pietro. With air there there
was no need to wear space suits, but it was so cold that we could take
it for only a minute or so. That was long enough to see a faint, fine
mist of dry ice snow falling. It was also long enough to catch a sight
of the three bodies there. I didn't enjoy that, and Pietro gasped.
Muller grimaced. When we came back, he sent Grundy in to move the
bodies to a hull-section where our breathing air wouldn't pass over
them. It wasn't necessary, of course. But somehow, it seemed
important.

By lunch, the air seemed normal. We shipped only pure oxygen at about
three pounds pressure, instead of loading it with a lot of useless
nitrogen. With the carbon dioxide cut back to normal levels, it was as
good as ever. The only difference was that the fans had to be set to
blow in a different pattern. We celebrated, and even Bullard seemed to
have perked up. He dug out pork chops and almost succeeded in making
us cornbread out of some coarse flour I saw him pouring out of the
food chopper. He had perked up enough to bewail the fact that all he
had was canned spinach instead of turnip greens.

But by night, the temper had changed--and the food indicated it again.
Bullard's cooking was turning into a barometer of the psychic
pressure. We'd had time to realize that we weren't getting something
for nothing. Every molecule of carbon-dioxide that crystallized out
took two atoms of oxygen with it, completely out of circulation.

* * * * *

We were also losing water-vapor, we found; normally, any one of our
group knew enough science to kno