it, marveled that the architect had been able to keep her sex a secret
all the time they were exploring at Mercury. They did not know that none
of E. Williams Jackson's fellow architects had ever guessed the truth.
Ambitious and ingenious, with a natural liking for house-planning, she
had resolved that her sex should not stand in the way of success.

And when she finally came to herself, there in her bunk, and suspected
that her secret was out--instead of shame or embarrassment she felt only
chagrin. She walked, rather unsteadily, across the floor of the great
cube-shaped car to the window where the three were standing; and as they
quietly made a place for her, she took it entirely as a matter of
course, and without a word.

The doctor had been speaking of the peculiar fitness of the four for
what they were doing. "And if I'm not mistaken," he went on, "we're
going to need all the brains we can pool, when we get to Venus.

"I never would have claimed, when we started out, that Mercury had ever
been inhabited. But now that we've seen what we've seen, I feel dead
sure that Venus once was peopled."

The four looked out the triple-glazed vacuum-insulated window at the
steadily growing globe of "Earth's twin sister." Half in sunlight and
half in shadow, this planet, for ages the synonym for beauty, was now
but a million miles away. She looked as large as the moon; but instead
of a silvery gleam, she showed a creamy radiance fully three times as
bright.

"Let's see," reflected the geologist aloud. "As I recall it, the
brightness of a planet depends upon the amount of its air. That would