Roger and Billy Dill to the spot from whence they had come.
"Borden is very anxious to have the three Englishmen held," said the senator's son.
"I suppose he wants to get back his money," returned Dave. "I don't blame him."
The path was through the forest and then along a rocky ridge. Here walking was very uncertain, and Roger warned the others to be careful.
"An' if ye ain't careful ye'll go into a hole to Kingdom Come!" put in Billy Dill.
When the ridge was left behind they came to another patch of timber, and then walked through a small cave with a large opening at either end. In the center of this cave was a hole, at the bottom of which flowed an underground river.
"If ever an island was rightly named, this is the one," observed Phil. "It is caves from one end to the other."
"Listen! I thought I heard voices!" exclaimed Dave, suddenly, and held up his hand for silence.
All listened closely and heard a faint murmur, coming from a distance.
"Sounds to me as if it was underground," whispered Phil.
"Yes, but from what direction?" asked Roger.
"I think it comes from over yonder," answered Dave. "Let us go there and make sure."
