Bob clutched his companion's arm.
"Something has happened to Peg!" he exclaimed. "Perhaps the guide has thrown him over, and he's lost, and scared nearly to death!"
But Frank was more accustomed to reading voices in the open than was his chum.
"No, you're wrong there!" he cried, "that's Spanish Joe yelping; and he must be in a bad hole to call for his companions. Come on, Bob, we've just got to see what we can do to help him. Rascal that he is, he's human. Follow me!"
CHAPTER XV
SPANISH JOE DROPS A CLUE
"Where can he be, Frank?" cried Bob, after they had been climbing for several minutes up the side of the rough mountain, almost groping their way, such was the darkness around them.
"Listen!"
"Help! Nick, this way, quick, or I'll go under!" came a shrill shout, only a little way above them.