to him, and with
the murder of Noel on his conscience, he feared to say anything to the
doctor about the snuff box while I was present. I imagine he suspected a
trap of some sort. But the doctor will discover, probably before the day
is out, how he has been tricked. Then he will begin to investigate, and
if he finds out that it was my wife who admitted the man, he may in his
rage decide to retaliate upon her. I cannot think of leaving Brussels,
without her. She must go with me. Upon that I am determined."

Dufrenne looked grave, and a glint of anger came into his eyes. "The
service of France, monsieur, is more important than your private
affairs. I beg of you that you leave here at once."

"But why, my friend? We can leave just as well in the morning. The box
is safe." He felt his waistcoat pocket.

"Safe, monsieur! Let me tell you that neither the box nor you yourself
are safe for a moment, as long as you remain in Brussels. You would be
in no greater danger, if you were carrying about with you a package of
dynamite."

"You are unduly nervous, monsieur," laughed Duvall, as he observed the
Frenchman's look of terror. "I have every confidence in my ability to
take care of myself. I must notify my wife to join me here as soon as
possible."

"How do you propose to do so?" inquired Dufrenne.

For a moment Duvall was puzzled. "You could not safely call her up by
telephone," the Frenchman continued. "For her to leave the sanatorium
now, in response to such a call, would attract the doctor's suspicion at
once. He is probably quite well aware of the fact that she knows no one
in Brussels. If he should have her followed here, and see her meet you,
he would at once conclude that there was something wrong about the whole
affair. He is very well known here in Brussels, and very powerful.
Undoubtedly he would have you both arrested on some pretext. Once you
are searched, and the snuff box taken from you, all our work is lost."

His earnest face, his frightened tones, disturbed the detective greatly.
He saw the force of Dufrenne's arguments, yet the thought of leaving
Grace to bear the brunt of Dr. Hartmann's anger was not to be considered
for a moment. He looked out of the window in silence for a long time,
trying to think out some plan that would insure Grace's safety. A gentle
tapping at the door caused him to turn. He nodded to Dufrenne, who at
once went to the door and opened it.

The newcomer proved to be Lablanche, of