"Keep your weather-eye open, Bounce," said Martin, turning toward the dog. "Our rifles are damp. If there is a wildcat in the neighborhood, you must do the fighting. Do you hear, old fellow?"
Bounce shook his head as if to say there was no danger while in his company.
After plodding along and elbowing their way through the damp bushes, the boys reached a hill which ran along the bank of the river for many miles, rising at times to the height of some three hundred feet. Carefully they clambered up toward the two giant rocks which could scarcely be discerned in the gloom, Bounce occasionally giving a low growl of alarm as they approached.
Again and again they stopped and listened, but nothing could be seen or heard. They therefore concluded that it was only a fresh trail, and that the animal itself was not near.
"I tell you it's dark," said Martin, who was the first to pass between the two immense rocks into the cavern.
"Dark as a dungeon," replied Owen in a tone of voice that showed he was not exactly pleased with the situation.
"All we need is a little fire to make things look home-like," said Martin, at the same time searching for some dry wood.
As no wood could be found the boys were forced to remain in the dark cave. Crouched together in a dry corner they tried to sleep, but could not. Bounce continued to growl, and, since he never gave a false alarm, they did not feel perfectly at ease. A strange and subdued sound seemed to issue from the crevices of the rocks. Both boys listened, yet neither spoke. Was it the dripping of the water from the damp arches above? What could it be?
"Didn't you hear something?" asked Martin.
"I thought so," replied Owen, "but, when I listened again, I heard nothing except the dripping water."