“That’s what we are going to do here—that is, if the chain is not too weak from age to bear us,” replied Frank.
“Do you really mean that?” demanded Harry.
“I certainly do,” rejoined Frank.
“Listen!” suddenly cried Billy, “did you fellows hear something?”
They all three paused and listened intently.
From far down in the dark pit that gaped at their feet there came a sound that seemed like a long drawn-out sigh.
CHAPTER XVIII.
THE RAVINE OF THE WHITE SNAKES.
The sound was not repeated; but, perhaps it was because the long spell in the darkness had got on their nerves, or possibly there was some sort of uncanny influence in the air of the long deserted place; but on at least two of the party, namely Harry and Billy, the chasm had a most depressing effect. Not so with Frank. Difficulties only increased his determination to conquer them.
“Come,” said the boy leader briskly, “if we are going to jump out of our skins and get nervous at every noise we hear we won’t get very far with our exploration. Probably there is a subterranean stream at the bottom of that pit. I have often read of underground rivers.”