nd give the alarm.

Acting upon the decision, he made his way across the basin to
where he had slid down the embankment and slowly and laboriously
climbed to the top, followed by Ab.

Retracing his steps, he soon reached the railroad and looking
down the track toward Pachuca gave a shout of delight as he saw
his three chums approaching, leading a fourth horse between them.

"Just in time," he said, as they drew near enough to exchange
greetings.

"Just in time for what?" queried the others as one.

"To capture the bandits that you let escape."

"How do you know that we let any escape?" asked Adrian.

"I'm a mind reader."

The other three looked incredulous.

"Oh, it's a fact," declared Billie. "I can tell you all about the
fight just as well as though I had been there," and he proceeded
to prove his words.

"Some one told you," said Adrian.

"Sure," laughed Billie, thoroughly enjoying the perplexity of
his companions. "My friend Ab. Come here, old man, and be
introduced," and Billie waved his whip, which he still carried.

With a little cry the ape sprang to his side, an act which only
added to the amazement of the others.

"Allow me," said Billie with mock gravity, "to introduce my
friend Mr. Ab from No-man's-land. Ab, these are the rest of the
Broncho Rider Boys. How would you like to join the company?"

Ab scratched his ear and looked wise.

"Oh, come," interrupted Donald. "Tell us what's up and what we
must do to capture the rest of this band of cutthroats."

Thinking that he had carried the joke far enough, and realizing
also that he might be wasting valuable time, Billie related his
adventure, describing the place he had discovered.

"It is the Rosario viejo," said Pedro, as soon as Billie had
finished his story.

"What's that?" asked Billie.

"An abandoned mine. It is called the old Rosario to distinguish
it from the new Rosario, which is now one of the most valuable
mines in this region. The station at Pitahaya was built
especially to serve it."

"I see," said Billie. "Where is the new mine?"

"Down there," and Pedro pointed to a trail leading in the
opposite direction. "It is just about as far from the station on
that side of the railroad as the old Rosario is on this."

"Don't you think we had better summon some assistance from the
mine workers?" asked Adrian.

"They may be in cahoots with the bandits," laughed Donald. "I
have lost my confidence in about every one in this bandit