"Why, that some cannibal tribe that Muley-Hassan pillaged for slaves at some time has trailed him and attacked him," hazarded the reporter.
How near he came to the truth our readers know. The band that had made the midnight attack was the same that had painstakingly trailed Muley-Hassan since he destroyed the boys' camp on the river bank.
"But the Arabs have beaten them off?" queried Lathrop.
"Evidently," replied Billy, as the volleys died out and victorious Arab shouts were beard. "Hark at that! It's really too bad. I'd like to have seen old Muley and his precious band driven into the river. But if they have driven off the savages they'll be thinking about chasing us."
As he spoke there came a low, growling sound that seemed to proceed from some distance, but nevertheless filled the air. It rumbled and rolled above them like—
"Thunder!" exclaimed both boys in the same breath.
"We've got to find shelter of some kind, quick," exclaimed Billy; "these tropical storms are unlike our little disturbances, and if we get caught among these trees in one, of them we stand a good chance of being killed. It looks like we've jumped out of the frying-pan into the fire."
Without the least idea in which direction they were proceeding, the two chums struggled bravely on, Billy encouraging the flagging Lathrop from time to time with a joke, though these latter were, as Billy admitted to himself:
"Pretty dismal!"
At length, just as dawn was beginning to break, they found themselves facing a steepish cliff of rough rocks.