"Well?"
"I will then take Monsieur Destange to the house of Monsieur Detinan; we will descend the servant's stairway which was used by you and Arsène Lupin when you escaped from Ganimard, and we will search together the means of communication with the adjoining house, which fronts on the Boulevard des Batignolles, and not upon the rue Clapeyron."
"Well?"
"I will take Monsieur Destange to the château de Crozon, and it will be easy for him, who knows the nature of the work performed by Arsène Lupin in the restoration of the Château, to discover the secret passages constructed there by his workmen. It will thus be established that those passages allowed the blonde Lady to make a nocturnal visit to the Countess' room and take the blue diamond from the mantel; and, two weeks later, by similar means, to enter the room of Herr Bleichen and conceal the blue diamond in his tooth-powder—a strange action, I confess; a woman's revenge, perhaps; but I don't know, and I don't care."
"Well?"
"After that," said Herlock Sholmes, in a more serious tone, "I will take Monsieur Destange to 134 avenue Henri-Martin, and we will learn how the Baron d'Hautrec——"
"No, no, keep quiet," stammered the girl, struck with a sudden terror, "I forbid you!... you dare to say that it was I ... you accuse me?..."
"I accuse you of having killed the Baron d'Hautrec."
"No, no, it is a lie."
"You killed the Baron d'Hautrec, mademoiselle. You entered his service under the name of Antoinette Bréhat, for the purpose of stealing the blue diamond and you killed him."
"Keep quiet, monsieur," she implored him. "Since you know so much, you must know that I did not murder the baron."
"I did not say that you murdered him, mademoiselle. Baron d'Hautrec was subject to fits of insanity that only Sister Auguste could control. She told me so herself. In her absence, he must have attacked you, and in the course of the struggle you struck him in order to save your own life. Frightened at your awful situation, you rang the bell, and fled without even taking the blue diamond from the finger of your victim. A few minutes later you returned with one of Arsène Lupin's accomplices, who was a servant in the adjoining house, you placed the baron on the bed, you put the room in order, but you were afraid to take the blue diamond. Now, I have told you what happened on that night. I repeat, you did not murder the baron, and yet it was your hand that struck the blow."
She had crossed them over her forehead—those long delicate white hands—and kept them thus for a long time. At last, loosening her fingers, she said, in a voice rent by anguish:
"And do you intend to tell all that to my father?"
"Yes; and I will tell him that I have secured as witnesses: Mademoiselle Gerbois, who will recognize the blonde Lady; Sister Auguste, who will recognize Antoinette Bréhat; and the Countess de Crozon, who will recognize Madame de Réal. That is what I shall tell him."
"You will not dare," she said, recovering her self-possession in the face of an immediate peril.
He arose, and made a step toward the library. Clotilde stopped him:
"One moment, monsieur."
She paused, reflected a moment, and then, perfect mistress of herself, said:
"You are Herlock Sholmes?"
"Yes."
"What do you want of me?"
"What do I want? I am fighting a duel with Arsène Lupin, and I must win. The contest is now drawing to a climax, and I have an idea that a hostage as precious as you will give me an important advantage over my adversary. Therefore, you will follow me, mademoiselle; I will entrust you to one of my friends. As soon as the duel is ended, you will be set at liberty."
"Is that all?"
"That is all. I do not belong to the police service of this country, and, consequently, I do not consider that I am under any obligation ... to cause your arrest."
She appeared to have come to a decision ... yet she required a momentary respite. She closed her eyes, the better to concentrate her thoughts. Sholmes looked at her in surprise; she was now so tranquil and, apparently, indifferent to the dangers which threatened her. Sholmes thought: Does she believe that she is in danger? Probably not—since Lupin protects her. She has confidence in him. She believes that Lupin is omnipotent, and infallible.
"Mademoiselle," he said, "I told you that we would leave here in five minutes. That time has almost expired."
"Will you permit me to go to my room, monsieur, to get some necessary articles?"
"Certainly, mademoiselle; and I will wait for you in the rue Montchanin. Jeanniot, the concierge, is a friend of mine."
"Ah! you know...." she said, visibly alarmed.
"I know many things."
"Very well. I will ring for the maid."
The maid brought her hat and jacket. Then Sholmes said:
"You must give Monsieur Destange some reason for our departure, and, if possible, let your excuse serve for an absence of several days."
"That shall not be necessary. I shall be back very soon."
"They exchanged defiant glances and an ironic smile.
"What faith you have in him!" said Sholmes.
"Absolute."
"He does everything well, doesn't he? He succeeds in everything he undertakes. And whatever he does receives your approval and cooperation."
"I love him," she said, with a touch of passion in her voice.
"And you think that he will save you?"
She shrugged her shoulders, and, approaching her father, she said:
"I am going to deprive you of Monsieur Stickmann. We are going to the National Library."
"You will return for luncheon?"
"Perhaps ... no, I think not ... but don't be uneasy."
Then she said to Sholmes, in a firm voice:
"I am at your service, monsieur."
"Absolutely?"
"Quite so."
"I warn you that if you attempt to escape, I shall call the police and have you arrested. Do not forget that the blonde Lady is on parole."
"I give you my word of honor that I shall not attempt to escape."
"I believe you. Now, let us go."
They left the house together, as he had predicted.
The automobile was standing where Sholmes had left it. As they approached it, Sholmes could hear the rumbling of the motor. He opened the door, asked Clotilde to enter, and took a seat beside her. The machine started at once, gained the exterior boulevards, the avenue Hoche and the avenue de la Grande-Armée. Sholmes was considering his plans. He thought:
"Ganimard is at home. I will leave the girl in his care. Shall I tell him who she is? No, he would take her to prison at once, and that would spoil everything. When I am alone, I can consult my list of addresses taken from the 'account M.B.,' and run them down. To-night, or to-morrow morning at the latest, I shall go to Ganimard, as I agreed, and deliver into his hands Arsène Lupin and all his band."
He rubbed his hand, gleefully, at the thought that his duel with Lupin was drawing to a close, and he could not see any serious obstacle in the way of his success. And, yielding to an irrepressible desire to give vent to his feelings—an unusual desire on his part—he exclaimed:
"Excuse me, mademoiselle, if I am unable to conceal my satisfaction and delight. The battle has been a difficult one, and my success is, therefore, more enjoyable."
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