tell you
all about it! I won't be gone more than a minute."

"But hold on!" cried Sandy. "You mustn't go chasing down into the mine
now. That bum detective is there, and we don't want him to know that
we're anywhere within a hundred miles of this place."

"He doesn't know that we're here, either," commented Elmer. "His notion
is that he drove us all into the next state when he caused the mine to
be flooded. He thinks he has the whole mine to himself now."

"So he caused the mine to be flooded, did he?"

"Sure he did," was the curt reply. "The boys saw him digging away at the
wall which protects this dry mine from the wet one next door."

"So you saw him doing it, did you?"

"I didn't, because I haven't been in the mine before for any length of
time, but Jimmie and Dick saw him."

"We've been told that he made the trouble," Will agreed, "but we weren't
so very sure of it, after all. At least, we didn't have the proof. He
ought to get twenty years for that!"

"Well, if you keep asking me questions all night," Elmer declared, "I'll
never get the boys up here, and you'll never know why you were sent
here! You can come along with me if you want to."

"But how about this detective?" insisted Sandy.

"We ought to be able to get the boys up here without letting him know
that we are in the mine," answered Elmer. "We needn't travel with a fife
and drum corps ahead of us, nor even carry any lights down with us. He's
probably working in some inside chamber."

"All right," Will answered, "we've had our trip through the mine
tonight, so we'll let Tommy and Sandy go with you. Are you sure the boys
will come if you ask them to?"

"Sure they'll come!" was the reply.

The two boys drew on their rubber boots with which they had provided
themselves before taking up their quarters in the mine, and which they
had been too excited to use on a previous occasion, and Will loaned a
pair to Elmer, then they started down the ladders.

"It would be something of a joke if we should butt into that detective
now, wouldn't it?" Sandy laughed, as they passed down from the second
level.

"I shouldn't consider it much of a joke," replied Tommy. "We took a lot
of pains to make him think we'd gone out of town!"

As the boys walked softly down the center gangway they heard a fall of
rock which seemed to come from the passage next north. This passageway
was connected by the main one with a cross-heading situated perhaps
three hundred feet