as it is. Meanwhile you
may reassure madame. Point out to her that if Monsieur Boissegur signed
the letters Tuesday night he was, at least, alive; and if he came or
sent for the cigarettes Wednesday night, he was still alive. I shall
call at the embassy this afternoon. No, it isn't advisable to go with
you now. Give me your latch-key, please."

Monsieur Rigolot produced the key and passed it over without a word.

"And one other thing," Mr. Grimm continued, "please collect all the
revolvers that may be in the house and take charge of them yourself. If
any one, by chance, heard a burglar prowling around there to-night he
might shoot, and in that event either kill Monsieur Boissegur or--or
me!"

When the secretary had gone Mr. Campbell idly drummed on his desk as he
studied the face of his subordinate.

"So much!" he commented finally.

"It's Miss Thorne again," said the young man as if answering a question.

"Perhaps these reports I have received to-day from the Latin capitals
may aid you in dispelling that mystery," Campbell suggested, and Mr.
Grimm turned to them eagerly. "Meanwhile our royal visitor, Prince
Benedetto d'Abruzzi, remains unknown?"

The young man's teeth closed with a snap.

"It's only a question of time, Chief," he said abruptly. "I'll find
him--I'll find him!"

And he sat down to read the reports.

XIII

A CONFERENCE IN THE DARK

The white rays of a distant arc light filtered through the half-drawn
velvet hangings and laid a faintly illumined path across the
ambassador's desk; the heavy leather chairs were mere impalpable
splotches in the shadows; the cut-glass knobs of a mahogany cabinet
caught the glint of light and reflected it dimly. Outside was the vague,
indefinable night drone of a city asleep, unbroken by any sound that was
distinguishable, until finally there came the distant boom of a clock.
It struck twice.

Seated on a couch in one corner of the ambassador's office was Mr.
Grimm. He was leaning against the high arm of leather, with his feet on
the seat, thoughtfully nursing his knees. If his attitude indicated
anything except sheer comfort, it was that he was listening. He had been
there for two hours, wide-awake, and absolutely motionless. Five, ten,
fifteen minutes more passed, and then Mr. Grimm heard the grind and whir
of an automobile a block or so away, coming toward the embassy. Now it
was in front.

"Honk! Hon-on-onk!" it called plaintively. "Hon-on-onk! H