"We've only got to knock," said Mazeroux. "Our men will find the trapdoor and let us out. If not, we will break it down."
More blows echoed down the passage. Fifteen or twenty minutes after, the trapdoor gave way, and other voices now mingled with Weber's and Mazeroux's.
During this time, Don Luis examined his domain and perceived how extremely small it was. The most that he could do was to sit in it. It was a gallery, or, rather, a sort of gut, a yard and a half long and ending in an orifice, narrower still, heaped up with bricks. The walls, besides, were formed of bricks, some of which were lacking; and the building-stones which these should have kept in place crumbled at the least touch. The ground was strewn with them.
"By Jove!" thought Lupin, "I must not wriggle about too much, or I shall risk being buried alive! A pleasant prospect!"
Not only this, but the fear of making a noise kept him motionless. As a matter of fact, he was close to two rooms occupied by the detectives, first the boudoir and then the study, for the boudoir, as he knew, was over that part of his study which included the telephone box.
The thought of this suggested another. On reflection, remembering that he used sometimes to wonder how Count Malonyi's ancestress had managed to keep alive behind the curtain on the days when she had to hide there, he realized that there must have been a communication between the secret passage and what was now the telephone box, a communication too narrow to admit a person's body, but serving as a ventilating shaft.
As a precaution, in case the secret passage was discov-
