"I turned back and, passing the ladies' compartment and the lavatory, decided to take my seat in the one next it communicating with the corridor. But luck was against me: a pane of glass was broken and it was bitterly cold there; so I had to fall back on the only compartment left, the smoking one towards the front of the train." "Were there many of you there?" "I thought at first that I was going to have a fellow-traveller, for there was some luggage and a rug arranged on the seat. But the passenger must have been in the lavatory, for I didn't see him. I lay down on the other seat and went to sleep. When I got out of the train at Limoges, my fellow-traveller must have been in the lavatory again, for I remember quite distinctly that he was not on the opposite seat. I thought at the time how easy it would have been for me to steal his luggage and walk off with his valise: nobody would have seen me." Juve had listened intently to every word of the story. He asked for one further detail with a certain anxiety in his tone. "Tell me, sir, when you woke up did you have any impression that the baggage arranged on the seat opposite yours had been disturbed at all? Might the traveller, whom you did not see, have come in for a sleep while you yourself were asleep?" Gervais Aventin made a little gesture of uncertainty. "I can't answer in the affirmative, M. Juve. I did not notice that; and, besides, when I got into the compartment, the shade was pulled down over the lamp, and the curtains were drawn across the windows. I hardly saw how the things were arranged. And then, when I got out at Limoges I was in a hurry, and only thought about finding my ticket and jumping on to the platform. But I do not think the other fellow did take his place while I was asleep. I did not hear a sound, and yet I did not sleep at all heavily." "So you travelled in a first-class compartment in the slow train from Paris to Luchon on the night of the 23rd of December, and in that compartment there was the luggage of a traveller whom you did not see--who may not have been there?" "Yes," said Gervais Aventin, and, as the detective sat silent for a moment, he enquired: "Is my information too vague to be of any use to you?" Juve was wondering inwardly why the dickens Etienne Rambert was not in that compartment when, according to the depositions of the guard, he must have been there; but he said nothing of this. Instead, he said: "Your information is most valuable, sir. You have told me everything I wanted to know." Gervais Aventin displayed still more surprise. "Well," he said, "by way of return, M. Juve, tell me something which puzzles me. How did you know I travelled by that train that night?" The detective drew out his pocket-book, and from an inner pocket produced a first-class ticket, which he held out to the engineer.