come?"
"By the train."
"But I sent my automobile to meet you at the station."
"An official reception, eh? with music and fireworks! Oh! no, not for me. That is not the way I do business," grumbled the Englishman.
This speech disconcerted Devanne, who replied, with a forced smile:
"Fortunately, the business has been greatly simplified since I wrote to you."
"In what way?"
"The robbery took place last night."
"If you had not announced my intended visit, it is probable the robbery would not have been committed last night."
"When, then?"
"To-morrow, or some other day."
"And in that case?"
"Lupin would have been trapped," said the detective.
"And my furniture?"
"Would not have been carried away."
"Ah! but my goods are here. They were brought back at three o'clock."
"By Lupin."
"By two army-wagons."
Herlock Sholmes put on his cap and adjusted his satchel. Devanne exclaimed, anxiously:
"But, monsieur, what are you going to do?"
"I am going home."
"Why?"
"Your goods have been returned; Arsène Lupin is far away—there is nothing for me to do."
"Yes, there is. I need your assistance. What happened yesterday, may happen again to-morrow, as we do not know how he entered, or how he escaped, or why, a few hours later, he returned the goods."
"Ah! you don't know—"
The idea of a problem to be solved quickened the interest of Herlock Sholmes.
"Very well, let us make a search—at once—and alone, if possible."
Devanne understood, and conducted the Englishman to the salon. In a dry, crisp voice, in sentences that seemed to have been prepared in advance, Sholmes asked a number of questions about the events of the preceding evening, and enquired also concerning the guests and the members of the household. Then he examined the two volumes of the "Chronique," compared the plans of the subterranean passage, requested a repetition of the sentences discovered by Father Gélis, and then asked:
"Was yesterday the first time you have spoken hose two sentences to any one?"
"Yes."
"You had never communicated then to Horace Velmont?"
"No."
"Well, order the automobile. I must leave in an hour."
"In an hour?"
"Yes; within that time, Arsène Lupin solved the problem that you placed before him."
"I.... placed before him—"
"Yes, Arsène Lupin or Horace Velmont—same thing."
"I thought so. Ah! the scoundrel!"
"Now, let us see," said Sholmes, "last night at ten o'clock, you furnished Lupin with the information that he lacked, and that he had been seeking for many weeks. During the night, he found time to solve the problem, collect his men, and rob the castle. I shall be quite as expeditious."
He walked from end to end of the room, in deep thought, then sat down, crossed his long legs and closed his eyes.
Devanne waited, quite embarrassed. Thought he: "Is the man asleep? Or is he only meditating?" However, he left the room to give some orders, and when he returned he found the detective on his knees scrutinizing the carpet at the foot of the stairs in the gallery.
"What is it?" he enquired.
"Look.... there.... spots from a candle."
"You are right—and quite fresh."
"And you will also find them at the top of the stairs, and around the cabinet that Arsène Lupin broke into, and from which he took the bibelots that he afterward placed in this armchair."
"What do you conclude from that?"
"Nothing. These facts would doubtless explain the cause for the restitution, but that is a side issue that I cannot wait to investigate. The main question is the secret passage. First, tell me, is there a chapel some two or three hundred metres from the castle?"
"Yes, a ruined chapel, containing the tomb of Duke Rollo."
"Tell your chauffer to wait for us near that chapel."
"My chauffer hasn't returned. If he had, they would have informed me. Do you think the secret passage runs to the chapel? What reason have—"
"I would ask you, monsieur," interrupted the detective, "to furnish me with a ladder and a lantern."
"What! do you require a ladder and a lantern?"
"Certainly, or I shouldn't have asked for them."
Devanne, somewhat disconcerted by this crude logic, rang the bell. The two articles were given with the sternness and precision of military commands.
"Place the ladder against the bookcase, to the left of the word Thibermesnil."
Devanne placed the ladder as directed, and the Englishman continued:
"More to the left.... to the right....There!....Now, climb up.... All the letters are in relief, aren't they?"
"Yes."
"First, turn the letter I one way or the other."
"Which one? There are two of them."
"The first one."
Devanne took hold of the letter, and exclaimed:
"Ah! yes, it turns toward the right. Who told you that?"
Herlock Sholmes did not reply to the question, but continued his directions:
"Now, take the letter B. Move it back and forth as you would a bolt."
Devanne did so, and, to his great surprise, it produced a clicking sound.
"Quite right," said Sholmes. "Now, we will go to the other end of the word Thibermesnil, try the letter I, and see if it will open like a wicket."
With a certain degree of solemnity, Devanne seized the letter. It opened, but Devanne fell from the ladder, for the entire section of the bookcase, lying between the first and last letters of the words,
