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, Lycée 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 Ambrumésy 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, clustering 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.”