dder and moved out into the center gangway. They
could see a light flickering some distance in advance, and had no
difficulty in following it.

"That's an electric torch!" Will commented.

"Perhaps, if we follow along, we'll be able to track them to their
nest," George suggested, "and, still, I don't care about getting very
far away from the shaft. We might get lost in these crooked passages."

"Yes," replied Will. "Some one might head us off, too. I don't care
about being held up here in pajamas."

The mine was damp and cold, and a wind was sweeping up the passage
toward the shaft. The boys shivered as they walked, yet kept resolutely
on until the light they were following left the main gangway and
disappeared in a cross heading.

"That means 'Good-night' for me," whispered Will, "for I'm not going to
get out beyond the reach of the rails. I guess well have to go back and
invent some other means of trapping those foxy boys."

As Will spoke the light reappeared and moved on down the gangway again.
Then, for the first time, the boys saw a figure outlined against the
illumination. Will caught his chum by the arm excitedly.

"That isn't one of the boys at all!" he exclaimed.

"Well, how large a population do you think this mine has!" demanded
George. "If it isn't one of the boys, who is it?"

"That bum detective!" answered Will.

"So he got in here at last, did he?" chuckled George. "Well, it's up to
us to find out what he's doing in here!"

"Do you think that is the gink who was prowling around our room?" asked
Will. "If he is, then our little trip in the country doesn't count for
much!"

"The fellow who visited us," George argued, "was light and quick on his
feet. This bum detective waddles along like an old cow."

"Then we've passed the boy who called to see us, and failed to leave a
card," grinned Will. "We may meet him as we return!"

"Here's hoping we bump straight into him if we do meet him," George
exclaimed. "I'm just aching to get my hands on that fellow!"

"I'm not particularly anxious to catch him just yet," Will suggested. "I
want to find out what the kids are up to before we pounce down upon
them."

While the boys stood in the passage, whispering together, the light
moved on until it came to a chamber which seemed to be rather shallow,
for the reflection of the searchlight was still in the gangway.

"Now we've got him!" exclaimed Will. "I think I remember that chamber,
and, unless I'm ver