s possible to
slow down only at the last moment. Otherwise....

Otherwise what?

There was no escape from the conclusion--otherwise heredity was altered
and mutations would result. Marlowe sat back. This was true without
exception. It was the biggest factor that controlled the conditions of
interplanetary flight. But--

_They'd had their children!_

Marlowe's pulse increased. As training director, he'd learned not to
leap at things that merely looked good. He had to examine them
carefully. But--well, it was a new approach, though he couldn't really
expect anything from it. There was more to a crew than a pilot, more to
space flight than one incredible lucky voyage, for angels took
vacations, too.

"You weren't on duty at all times," Marlowe pointed out. "Then there's
navigation."

"Don't sleep much," said Ethan. "Catnap once in a while." He thought it
over. "When I did sleep, 'Mantha helped out." He looked at her. "I'm not
the expert on navigation. You'd better ask her."

"_No!_" cried Marlowe.

"Why not? Just because I'm a woman?" Her eyes were bright.

"But who taught you navigation?"

Amantha sniffed. "Look here, young man, don't tell me what I can learn."
She closed her eyes and imagination carried her back to the ship. "Lots
of dials and gadgets--but I used to have near as many in my kitchen
before they said I was too old to cook. Anyway, you don't have to figure
it out on paper. If you look at things just right, you sort of know
where you are."

* * * * *

Amantha folded her hands. "First, you take a big handful of the Sun's
attraction and mix it with a bigger scoop of the gravitation of the
planet you happen to be on. For us, that was Mars. Then you add a pinch
of acceleration. That's what makes you rise. When you get out a ways,
you decrease Mars and add more Earth and another pinch of Sun, stirring
it around in your mind each day until it feels just right."

She smiled. "I never did hold with too much measuring."

The muscles in Marlowe's chest felt cramped from holding his breath in.
While she spoke, he could almost believe she knew what she was doing,
that she had a knack for it. Perhaps she did--brief flashes of clarity
swept over her senile, beclouded mind. And the same with the old man.
These instances of sanity--and luck--had pulled them through.

The ship was back, unharmed. He shouldn't ask for more. And yet--they
had made it to Earth.

The chute in t