"I have no profession."

"But look here, sir," cried the magistrate, with a certain asperity, "you can't expect to preserve your incognito after introducing yourself here by a trick and surprising the secrets of the police!"

"I beg to remark, Monsieur le Juge d'Instruction, that you asked me nothing when I came in, and that therefore I had nothing to say. Besides, it never struck me that your inquiry was secret, when everybody was admitted-including even one of the criminals!"

He spoke softly, in a tone of infinite politeness. He was quite a young man, very tall, very slender and dressed without the least attempt at fashion, in a jacket and trousers both too small for him. He had a pink face like a girl's, a broad forehead topped with close-cropped hair, and a scrubby and ill-trimmed fair beard. His bright eyes gleamed with intelligence. He seemed not in the least embarra.s.sed and wore a pleasant smile, free from any shade of banter.

M. Filleul looked at him with an aggressive air of distrust. The two gendarmes came forward. The young man exclaimed, gaily:

"Monsieur le Juge d'Instruction, you clearly suspect me of being an accomplice. But, if that were so, would I not have slipped away at the right moment, following the example of my fellow-criminal?"

"You might have hoped-"

"Any hope would have been absurd. A moment's reflection, Monsieur le Juge d'Instruction, will make you agree with me that, logically speaking-"

M. Filleul looked him straight in the eyes and said, sharply:

"No more jokes! Your name?"

"Isidore Beautrelet."

"Your occupation?"

"Sixth-form pupil at the Lycee Janson-de-Sailly."

M. Filleul opened a pair of startled eyes.

"What are you talking about? Sixth-form pupil-"

"At the Lycee Janson, Rue de la Pompe, number-"

"Oh, look here," exclaimed M. Filleul, "you're trying to take me in! This won't do, you know; a joke can go too far!"

"I must say, Monsieur le Juge d'Instruction, that your astonishment surprises me. What is there to prevent my being a sixth-form pupil at the Lycee Janson? My beard, perhaps? Set your mind at ease: my beard is false!"

Isidore Beautrelet pulled off the few curls that adorned his chin, and his beardless face appeared still younger and pinker, a genuine schoolboy's face. And, with a laugh like a child's, revealing his white teeth:

"Are you convinced now?" he asked. "Do you want more proofs? Here, you can read the address on these letters from my father: 'To Monsieur Isidore Beautrelet, Indoor Pupil, Lycee Janson-de-Sailly.'"

Convinced or not, M. Filleul did not look as if he liked the story. He asked, gruffly:

"What are you doing here?"

"Why-I'm-I'm improving my mind."

"There are schools for that: yours, for instance."

"You forget, Monsieur le Juge d'Instruction, that this is the twenty-third of April and that we are in the middle of the Easter holidays."

"Well?"

"Well, I have every right to spend my holidays as I please."

"Your father-"

"My father lives at the other end of the country, in Savoy, and he himself advised me to take a little trip on the North Coast."

"With a false beard?"

"Oh, no! That's my own idea. At school, we talk a great deal about mysterious adventures; we read detective stories, in which people disguise themselves; we imagine any amount of terrible and intricate cases. So I thought I would amuse myself; and I put on this false beard. Besides, I enjoyed the advantage of being taken seriously and I pretended to be a Paris reporter. That is how, last night, after an uneventful period of more than a week, I had the pleasure of making the acquaintance of my Rouen colleague; and, this morning, when he heard of the Ambrumesy murder, he very kindly suggested that I should come with him and that we should share the cost of a fly."

Isidore Beautrelet said all this with a frank and artless simplicity of which it was impossible not to feel the charm. M. Filleul himself, though maintaining a distrustful reserve, took a certain pleasure in listening to him. He asked him, in a less peevish tone:

"And are you satisfied with your expedition?"

"Delighted! All the more as I had never been present at a case of the sort and I find that this one is not lacking in interest."

"Nor in that mysterious intricacy which you prize so highly-"

"And which is so stimulating, Monsieur le Juge d'Instruction! I know nothing more exciting than to see all the facts coming up out of the shadow, cl.u.s.tering together, so to speak, and gradually forming the probable truth."

"The probable truth! You go pretty fast, young man! Do you suggest that you have your little solution of the riddle ready?"

"Oh, no!" replied Beautrelet, with a laugh.

"Only-it seems to me that there are certain points on which it is not impossible to form an opinion; and others, even, are so precise as to warrant-a conclusion."

"Oh, but this is becoming very curious and I shall get to know something at last! For I confess, to my great confusion, that I know nothing."

"That is because you have not had time to reflect, Monsieur le Juge d'Instruction. The great thing is to reflect. Facts very seldom fail to carry their own explanation!"

"And, according to you, the facts which we have just ascertained carry their own explanation?"

"Don't you think so yourself? In any case, I have ascertained none besides those which are set down in the official report."

"Good! So that, if I were to ask you which were the objects stolen from this room-"

"I should answer that I know."

"Bravo! My gentleman knows more about it than the owner himself. M. de Gesvres has everything accounted for: M. Isidore Beautrelet has not. He misses a bookcase in three sections and a life-size statue which n.o.body ever noticed. And, if I asked you the name of the murderer?"

"I should again answer that I know it."

All present gave a start. The deputy and the journalist drew nearer. M. de Gesvres and the two girls, impressed by Beautrelet's tranquil a.s.surance, listened attentively.

"You know the murderer's name?"

"Yes."