letter but through no fault of mine. I was acquitted of further
responsibility; was at liberty to choose. And Mrs. Buissard agreed with
me in everything. In the end, I accepted the spurious letter for
delivery to the French Ambassador."

"Good!" Harleston applauded. "You're learning the method of diplomacy
very rapidly; fire with fire, ruse with ruse, deceit with
deceit--anything for the object in hand."

"It went against me to do it," she admitted, "but I'll pay them in their
own coin--or something to that effect. Of course, I've no intention of
delivering the letter to the French Embassy. I'll deliver it to you
instead."

"Delightful!" Harleston exclaimed. "You're a bully diplomat. However,
I'm not so sure that Spencer ever imagined her letter would reach the
Marquis. She's playing for something else, though what is by no means
clear. Let us have a look at the letter; maybe it will help."

She stood beside him as he cut the envelope and he took out the single
sheet of paper--on which was an assortment of letters, set down
separately and without relation to words.

"What is it," said she, "a scrambled alphabet?"

"Looks like it!" he smiled. "As a matter of fact, however, it's in the
Blocked-Out Square cipher--like the original lett--"

"Then they could read the original?" she cut in.

"Not unless they have its particular key-word--"

"Oh, yes; I remember now," said she. "Go on!"

"There's no 'go on,'" he explained. "Nor would it help matters if there
were. This letter is spurious; there is nothing to find from it, even if
we could translate it. It's intended as a plant; either for us or for
the Marquis; but I fancy, for us--so with your permission we will waste
no time on it further than to keep alert for its purpose. When were you
to receive the five thousand dollars?"

"I don't know!" she laughed.

"And the appointment to the German Secret Service?"

"I don't know; she didn't say and I didn't ask. I was too much occupied
with meeting her on her own ground and playing the game. I was crazy to
get the letter so I could show it to you."

"Which doubtless was what she too wanted; I can't see through her
scheme--unless it is to muddy the water while the main play is being
pulled off. And our men haven't discovered a single material thing,
though they have had Spencer and all the rest of the gang under shadow
since the morning after the cab affair."

The telephone buzzed. Mrs. Clephane answered it.

"Y