ks," Marston observed.

She nodded slightly.

"Which of these do you fancy is the key-word?" she asked.

"We shall try them in turn, beginning with the last: _a l'aube du jour_.
I've a hunch that we'll end there."

"And that you'll go into temporary confinement?" she smiled.

"My hunch stops with the key-word!" he smiled back.

"Your hunch as to the key-word is partially correct," she replied
slowly, "but it does not, however, reach quite to the last conclusion. I
may not explain now, Marston. Do you go to the meeting, with the
code-book as your only exhibit. It should be indisputable proof of your
good faith, and our honest belief that the letter does not concern the
United States. Moreover, you run no danger of imprisonment, for you'll
not effect a translation. But you must obtain a copy of the letter; it's
but a fair exchange for the French code, you know; and you're
permitted--nay you're authorized, in the interest of the service--to
allow Carpenter to copy the book if he will give you the letter to copy.
Furthermore, you may proceed leisurely in the process; there is no
particular haste; while they are occupied with the letter matter, there
is apt to be less activity along other lines. Only get a _copy of the
letter_; I have the key-word."

"You have the key-word!" Marston exclaimed.

She nodded. "I'm quite sure of it; and the code-book confirms me. It is
up to you to procure the letter; I'll do the rest, if any rest is
necessary. We may be headed for Europe by evening, Marston; in which
event, the cipher letter is of no consequence to us."

"You'll be glad to get back to Paris?" he asked.

"I shall, indeed--won't you?"

"I'm quite content anywhere, so long as I am working with you," he
answered. It was much as a faithful dog would wag his tail and snuggle
up for a pat of the hand.

She smiled straight into his eyes--a frank, appreciative smile, as
though an intimate camaraderie existed between them, and would never be
violated by either. She would have been in danger had she smiled that
way at some men; they would not have remained quiescent. And a little
more aggression by Marston might have been more conducive for
success--less of the faithful dog and more of the independent
subordinate and the equal human. As it was, he was only a plaything.

"Now, my friend, if you're done you may go," she said briskly. "I must
dress, and you're rather _de trop_ at such a time, however much you may
be welcome a