"You're the original little mystery boy, ain't you?" said Tommy rather crossly. "All right, I'll get even."
The detective now moved farther along the cross-cutting and attacked a column of mingled rock and coal which helped to support the roof.
"The blithering idiot is going to try that trick again!" exclaimed Dick. "He'll have the whole mine down on our heads if he doesn't stop that business. He's always cutting down pillars."
"Just say the word," declared Tommy, "and I'll go stop him!"
"Let him go his own gait," replied Dick. "We'll manage to keep out of the way of the falls, and he can run his own chances."
Presently they saw the detective take something which resembled a stick of dynamite from a pocket and begin the work of setting it into the pillar. The boys moved hastily back.
"Now what do you think of that for a fool?" exclaimed Dick. "He'll have the whole mine down on our heads some day, just as sure as he's a foot high! I hope he'll be broken in two when the fall comes."
The boys stood some distance away watching the detective as he awkwardly manipulated the stick of dynamite.