"Your friend's name was Marco. And you went for a walk in the cellars of the Crédit Lyonnais." "I? What an idea! . . . Marco! . . . I don't know any one by that name." "And these? Do you know these?" cried the chief, thrusting a pair of gold-rimmed spectacles under his nose. "No . . . certainly not. . . . I don't wear spectacles. . . ." "Yes, you do; you wear them when you go to the Crédit Lyonnais and when you pass yourself off as Mr. Kesselbach. These come from your room, the room which you occupy, under the name of M. Jérôme, at No. 50 Rue du Colisee." "My room? _My_ room? I sleep here, at the office." "But you change your clothes over there, to play your parts in Lupin's gang." A blow in the chest made him stagger back. Auguste reached the window at a bound, climbed over the balcony and jumped into the courtyard. "Dash it all!" shouted Valenglay. "The scoundrel!" He rang the bell, ran to the window, wanted to call out. M. Lenormand, with the greatest calm, said: "Don't excite yourself, Monsieur le Président . . ." "But that blackguard of an Auguste . . ." "One second, please. . . . I foresaw this ending . . . in fact, I allowed for it. . . . It's the best confession we could have. . . ." Yielding in the presence of this coolness, Valenglay resumed his seat. In a moment, Gourel entered, with his hand on the collar of Master Auguste Maximin Philippe Daileron, _alias_ Jérôme, chief messenger at the Ministry of the Interior. "Bring him, Gourel!" said M. Lenormand, as who should say, "Fetch it! Bring it!" to a good retriever carrying the game in its jaws. "Did he come quietly?" "He bit me a little, but I held tight," replied the sergeant, showing his huge, sinewy hand. "Very well, Gourel. And now take this chap off to the Dépôt in a cab. Good-bye for the present, M. Jérôme." Valenglay was immensely amused. He rubbed his hands and laughed. The idea that his chief messenger was one of Lupin's accomplices struck him as a most delightfully ludicrous thing. "Well done, my dear Lenormand; this is wonderful! But how on earth did you manage it?" "Oh, in the simplest possible fashion. I knew that Mr. Kesselbach was employing the Barbareux agency and that Lupin had called on him, pretending to come from the agency. I hunted in that direction and discovered that, when the indiscretion was committed to the prejudice of Mr. Kesselbach and of Barbareux, it could only have been to the advantage of one Jérôme, a friend of one of the clerks at the agency. If you had not ordered me to hustle things, I should have watched the messenger and caught Marco and then Lupin." "You'll catch them, Lenormand, you'll catch them, I assure you. And we shall be assisting at the most exciting spectacle in the world: the struggle between Lupin and yourself. I shall bet on you." * * * * * The next morning the newspapers published the following letter: "_Open Letter to M. Lenormand, Chief of the Detective-service._