"I do not think so, Monsieur. Since that last affair of ours there have been too many sentries in the yards, especially at night. It would be impossible to dig anywhere."
"We ought to do something, Dubec."
"Yes, Monsieur?"
"But the job is to know what," Dale struck in. "We can't tunnel underground, I suppose, and get at them that way, so we must find out by spying where the wires are run to—eh, Max?"
"Tunnel?" ejaculated Max. "That's an idea, Dale. Those old mines we were tracing in the plans the other day! Why not?"
"Why not what?" asked Dale a little testily.
"Why, you know we noticed that one of them ran right up to the outskirts of the city? Well, why shouldn't we continue it secretly, until we get beneath the yards, and then burrow upwards to the workshops? Then we can remove the mine-charges from below, and sit still and hold tight until the great day arrives."
"Hurrah!" cried Dale enthusiastically. "The very thing. Phew! what a coup it will be!"
"We shall, of course, have to get Dubec here and one or two others to arrange it for us. They must go to work in the Durend mines, and take it in turns to spend a night down there. Each man, as his turn comes, must go into the old workings, and continue the gallery fixed upon in the direction of the Durend works. Narrow seams of coal, not worth working, did run in that direction according to the plans, and they will have no difficulty in getting rid of the coal of course. The rock they hew out must be taken away and dumped in remote, abandoned workings, where it is not likely to be found or understood."
"'Pon my word, it sounds like the real thing," cried Dale with fresh enthusiasm. "But it'll take a long time I should think, so we must make a start at once. What do you think, Dubec?"