Richard Duvall looked at the tense figure, the agitated face of his companion, and once again a feeling of surprise swept over him, as he observed the little Frenchman's joy at the recovery of Monsieur de Grissac's snuff box.

Throughout the exciting events of the morning, and of the night before, the detective had lost sight of the apparent insignificance of the object of their search; now that he for the first time saw it before him, his curiosity was once more aroused. Surely there must be something of vast interest about this apparently worthless bit of ivory, to make its theft the reason for a brutal murder, its recovery a matter of such extreme importance that Monsieur Lefevre should consider the honor of his country at stake.

He took the box from Dufrenne's trembling fingers and examined it carefully. It was about two and a half inches in circumference, and quite shallow, not over half an inch in depth, in all. The ivory was old and yellow from use and time, and very thin and smooth. The lightness of the box surprised him—it seemed to weigh almost nothing, as he balanced it on the palm of his hand.

The circular top of the box was curiously ornamented with a circle of small colorless pearls, of trifling value, set at regular intervals about the edge of the cover. Within this row of pearls was an inscription in Latin, carved in tiny letters in the ivory. From its first words, "Pater noster," Duvall saw that it was the Lord's Prayer. The letters extended around the circumference of the box in several concentric lines, or rings, inside of the ring of pearls. In the center of the box was a cross of ivory, carved so as to be slightly raised above its general surface. Beyond this, the box contained no other ornamentation.

Along the front edge of the box Duvall noticed a small spring. He pressed it, in considerable excitement. Evidently the reason for the box's value must be within—some papers, no doubt, of extreme importance. He saw the cover of the box fly upward and glanced hastily inside. The box contained nothing but a few pinches of snuff.

Duvall was almost tempted to laugh. The whole thing seemed so ridiculous—so utterly absurd. Absent-mindedly he tried a pinch of the snuff, inhaling it into his nostrils. It produced nothing more startling than a violent fit of sneezing. Undoubtedly Monsieur de Grissac had told the truth. He did use snuff.

Closing the box, Duvall regarded it for a moment in silence, then looked at Dufrenne. "It isn't worth a hundred francs," he said.

"The box?" answered the curio dealer, as he followed Duvall's glances. "No, monsieur—what you say is indeed true, yet I would not sell it for a hundred million."

"But why? What is there about it that makes it so valuable? Surely you can tell me that, now that we have safely recovered it."

"Alas, monsieur. I could not tell you, even if I knew, which I assure you I do not. I can only say that Monsieur Lefevre has told me that it holds within it the honor of my beloved country, and therefore I would not sell it for all the money in the world."

Duvall was clearly puzzled. "Well," he said at length, as he thrust the box into his pocket, "there's evidently some mystery about the thing that I do not understand, but I suppose I shall, some day. Just at present our first duty is to return the box to Monsieur de Grissac."

"You are right, monsieur, and at once. There is a train for Antwerp in half an hour. From there we can take the night boat to Harwich. Let us set out without further delay."

"And that fellow in there?" remarked the detective with a grim laugh. "We've got to take him with us, you know. He'll be wanted in London for the murder of the man NoËl."

"Yes. That also is important." Dufrenne went into the adjoining room and stood looking at the sleeping barber. "But not so important as the return of the snuff box to Monsieur de Grissac."

Duvall followed him, and lifting one of Seltz's arms, let it drop suddenly. It fell to his side, lifeless. "He's sleeping like a log. The doctor must have given him a pretty stiff dose. I don't see how we are going to travel with him in this condition."

"Then we must leave him in the care of Monsieur Lefevre's other agents here in Brussels. We cannot delay an instant, on any account."

"I do not agree with you, monsieur. There is one thing which is as important to me as the recovery of the snuff box could possibly be to Monsieur de Grissac, and that is, the safety of my wife."

"Your wife?" Dufrenne stared at him in surprise.

"Yes, monsieur, my wife. She is at present in Dr. Hartmann's house. How she came there, I do not know, but I imagine that our friend the Prefect sent her there, to assist, if occasion offered, in our work. In that he was wise; but for her presence, I fear my plan would have failed. Had Seltz rung the doorbell, and been admitted by any of the doctor's servants, I doubt if I should have been able to get the box from him before the latter had seen him. I should then have been obliged to use force, and the results might have been disastrous."

"Yes, monsieur. I see that. The young lady at Dr. Hartmann's was sent by Monsieur Lefevre. His agents here have already informed me of that. But that she is your wife I did not know." He pondered for a moment, glancing at his watch. "It is a great pity. Delay may be most dangerous. Why do you not send her word to join you in Paris?"

Duvall frowned, and began to walk about the room nervously. "A few hours' delay can make no difference," he presently said. "The box is perfectly safe in our hands. I am not, however, at all convinced that my wife is perfectly safe in the hands of Dr. Hartmann."

"But he knows nothing?"

"That I cannot say. So far he does not, I think, suspect that Seltz was the man he expected from London. If he had, he would never have let me leave his office. Luckily for us, Seltz was a stranger to him, and with the murder of NoËl 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 the Prefect's office, whom Dufrenne had met earlier in the day. He bowed to Duvall, who knew him slightly, then glanced at the sleeping figure on the bed. "You have been successful, monsieur?" he inquired eagerly.

Duvall nodded. "This fellow"—he indicated Seltz—"must be taken to London as soon as he is in condition to travel. We will leave the matter to you."

"Excellent, monsieur. He shall be well taken care of. I presume that you and Monsieur Dufrenne will start at once."

"I desire first, Monsieur Lablanche, to get my wife from the house of Dr. Hartmann."

Lablanche gave a low whistle. "I should not advise you to attempt to communicate with her, monsieur."

"You think her sudden departure would make Hartmann suspicious?"

"Undoubtedly."

"Then we must arrange for her to come to Brussels this afternoon on some pretext. If she only had some friends in the city—"

"The American Minister, monsieur!" exclaimed Lablanche, suddenly. "He recommended her to Dr. Hartmann. It appears that he was at one time acquainted with your wife's people. Perhaps he would undertake to telephone to her. That would be entirely safe. But I beg of you, monsieur, do not let the Minister know what your wife's object in going to Dr. Hartmann's was. He knows her only as Miss Ellicott. He vouched for her to Hartmann. If he knew that he had been used, it would make him extremely angry."

For a few moments Duvall stood in silent thought, then picking up his hat, went toward the door. "I will see the American Minister at once," he said, as he went out. "Wait for me here, gentlemen. I will be back within an hour."

Mr. Phelps, the United States Minister, was busy in his cabinet when Duvall was announced. He took the card from his secretary and glanced at it carelessly. The detective's name caused him to start. "Richard Duvall," he said aloud, to his secretary. "Surely it can't be the well-known detective, yet the name—" He regarded the card, his forehead wrinkled with thought. Duvall's distinguished position as the author of several works on the science of criminology was well known to him. "Show him in," he said, at length, and began to relight his cigar.

Duvall was ushered in, and in a few moments had explained the object of his visit. "A young lady—a Miss Ellicott," he told the Minister, "had come to Brussels the night before, and had gone to Dr. Hartmann's as a patient." Mr. Phelps nodded, and added that he had met Miss Ellicott, and had used his influence to enable her to obtain Dr. Hartmann's services. "The doctor is a great friend of mine," the Minister remarked. "I regard him as one of the leading scientists of Europe."

"Undoubtedly," the detective assented gravely. "I am not acquainted with him, myself. My business is with Miss Ellicott."

"Then why have you come here?" asked Mr. Phelps, with some asperity. "The doctor's house is but a few moments' drive."

"I know that. But unfortunately I am not acquainted with Miss Ellicott. She might resent my calling on her so unceremoniously. I had hoped that you might ask her to come here, so that I might be properly introduced to her."

The Minister considered the matter carefully. Evidently he did not altogether like it. "You forget, Mr. Duvall," he said, finally, "that I myself do not know you. Furthermore I certainly have no desire to involve Miss Ellicott in any difficulties. I trust," he concluded, uneasily, "that she is not already so involved."

"No." The detective shook his head. "Not yet. But unless I can have a few words with her in private, she soon may be. I am working in her interests. I am here to protect her from a grave danger." He went toward the Minister, and, taking a package of papers from his pocket, placed them in the latter's hand. "Here are my credentials. From them you will see that I am what I represent myself to be. I cannot undertake to explain to you now the reasons which prevent me from going to Miss Ellicott where she is. The mere fact that I am unknown to her will, I trust, prove sufficient. I wish to say to her but a few words. She will be very glad to hear them, I know."

The Minister returned the papers to Duvall and glanced at the clock upon his desk. "We are having a few friends for dinner to-night, Mr. Duvall. I shall ask Miss Ellicott to join us. If you care to be one of the party—" He paused, looking at the other questioningly.

"I shall be very glad indeed to accept, Mr. Phelps. I assure you that I would under no circumstances force myself upon you in this way, were it not for Miss Ellicott's good. And, in order that your other guests may not by any chance identify me, may I ask that you will introduce me as Mr. Brooks?"

The Minister nodded. "Very well, if you wish it, Mr. Duvall. The whole affair strikes me as extremely unusual, and did I not know you to be a man of your word, I should have nothing to do with it. Under the circumstances, I will consent. At least, I feel sure that no harm can come to Miss Ellicott while she is under my roof."

The detective murmured his thanks. "You will be doing Miss Ellicott a great service, my dear sir," he said. "And one thing more. When you telephone to her, asking her to come, kindly do not mention the fact that I have called." He took the Minister's hand and pressed it warmly. "Some day you will realize the dangers with which Miss Ellicott is being threatened."

On his return to the Hotel Metropole, Duvall found everything as he had left it. Seltz was still sleeping soundly. Lablanche was reading a newspaper. Dufrenne was superintending the placing of Duvall's portmanteau, which had arrived from Paris in response to a hasty wire from him that morning. He had been without a change of linen since the day before, and the arrival of his baggage was gratifying.

He informed Lablanche of his plans. "I shall dine at the United States Minister's," he informed them, "as Mr. Brooks. After dinner I shall ask Miss Ellicott's permission to escort her home. We will take a cab and drive to the railway station in time for the midnight train for Paris. On my arrival there, I shall give the snuff box to Monsieur Lefevre, who will see that it is safely returned to the Ambassador in London. You, Lablanche, can go to London with Seltz as soon as the latter is sufficiently recovered to travel—in the morning, let us say. You, Dufrenne, will no doubt prefer to return with me to Paris. In that event, kindly settle with the hotel people for these rooms, and join me at the railway station." He paused, opened his traveling case, and drew out a suit of evening clothes.

Lablanche and Dufrenne withdrew into the adjoining room, where Seltz lay sleeping. The latter paused in the door as he went out. "Take care of the snuff box," he said, pointedly. "Remember—the honor of France."