uvall, and I compliment you upon your
ingenuity. Had you been as wise, yesterday, as you were clever, you
would have left Brussels before I discovered the trick you had played on
me. Why you did not do so--why you foolishly remained to dine at the
house of Mr. Phelps, I confess I cannot see. It is beyond me. But all
that is beside the case. You have the snuff box--at least you know where
it is. Are you going to turn it over to me, or must I force you to do
so?"

Duvall listened to the doctor with an impassive face. "I know nothing
about any snuff box," he returned, with a show of anger. "You are
wasting your time, Dr. Hartmann. I have nothing more to say on the
subject." He turned his back and gazed moodily out across the lawn.

Hartmann regarded him with a scowl of anger. "I give you until to-night,
Mr. Duvall, to do as I ask. After that, I shall be compelled to force
you to do so."

The detective shrugged his shoulders and turned to the door. "You use
strong words, my friend. If any harm comes to me, my government will
know how to deal with you." His threat did not seem to alarm the doctor
particularly. "Do not forget, Mr. Duvall," he said, with an evil smile,
"that while I know how to cure mental disorders, I also know how to
create them. Good-morning."

The grave threat in his words filled Duvall with uneasiness. What did
Hartmann mean? Did he propose to feed him with drugs, cunningly
concealed in his food, which would steal away his senses, and leave him
a babbling child? The thought was terrifying. Yet he had until to-night.
He decided to return to his room and think, hoping thus to evolve some
plan which might prove a solution of his difficulties. In the afternoon
he would communicate it to Grace, and she, in return, could send word to
Dufrenne, so that the latter might cooeperate with him.

He found everything in his room as he had left it, and, seating himself
by the window, was soon plunged in deep thought. The arrival of one of
the attendants with his luncheon some two hours later woke him from a
maze of profitless scheming. The problem was as yet still unsolved.

After luncheon, he decided to go down and have a talk with Grace. By
keeping away from the house, and walking through the shrubbery, he hoped
to be able to talk with her more freely. Much to his surprise, he found
the door of his room once more locked. He sat down with a feeling of
utter helplessness. The net was beginning to close about him.