"We shall see. . . . One thing at a time. . . . And then, Mr. Chapman, this Marco went away immediately after M. Gourel had rung the bell?"
"Yes, we heard him go."
"And after he went, did you hear nothing else?"
"Yes . . . from time to time, but vaguely. . . . The door was shut."
"And what sort of noises did you hear?"
"Bursts of voices. The man . . ."
"Call him by his name, Arsène Lupin."
"Arsène Lupin must have telephoned."
"Capital! We will examine the person of the hotel who has charge of the branch exchange communicating with the outside. And, afterward, did you hear him go out, too?"
"He came in to see if we were still bound; and, a quarter of an hour later, he went away, closing the hall-door after him."