"Well, let's go down," began Andy, "and see——"
He did not finish the sentence, for he suddenly disappeared from sight, crashing through some bushes with a clatter of earth and stones.
"Hello! What's the matter?" gasped Frank.
"Andy, where are you?" yelled Billy.
"Down in a hole!" was the answer, in muffled tones. "I fell half-way through to China, I guess. Look out, don't follow me here."
Andy had been off his horse when the accident happened, or it might have been more serious. Frank now leaped from his animal and cautiously approached the place where his brother had fallen in. He saw an opening into some sort of cave, but, almost as he reached it, Andy came walking out, for the floor of the cavern, that had been concealed by the brush, was sloping.
"Well, what are you trying to do?" asked Frank.
"You can search me," answered Andy, grimly. "I didn't know that cave was there any more than you did. But it sure is a hole."
"Let's have a look," suggested Billy, and with his two chums he began pulling aside the bushes. Soon a good-sized opening was revealed, leading into a cavern the depth or size of which it was impossible to determine in the fast-gathering darkness.
"Let's go in!" cried impetuous Andy.