An instant later the two men came in, speaking together in French.

The larger man had a gruff voice and spoke the language in a way that showed it was not native to him.
"When did you learn that he had changed his room ?" asked the man with the gruff voice.
"Only this afternoon," replied the conductor.
"Did you bore holes between that and the adjoining compartment ?" "Yes, Excellency; but Azof did not tell me whether you wanted the holes at the top or the bottom." "At the bottom, of course," replied the Russian.

"Any fool might have known that.

The gas must rise, not fall; then when he feels its effect and tumbles down, he will be in a denser layer of it, whereas, if we put it in the top, and he fell down, he would come into pure air, and so might make his escape.

You did not bore the hole over the top berth, I hope ?" "Yes, Excellency, but I bored one at the bottom also." "Oh, very well, we can easily stop the one at the top.