As they were wet to the knees, one after another got down in the stream and examined the rocks. Some thought they saw daylight under the water beyond the rocks, but nobody was sure.
"If it wasn't so cold a fellow could take a dive and find out," said Shep. "But I don't want a dive in such water as that," and the others agreed with him.
It was noontime and Whopper suggested that they have something to eat.
"I am willing," said Snap. "But don't eat too much. There is no telling how long we'll have to remain down here."
So they ate sparingly, and washed the meal down with water from the underground stream, which was as pure as it was cold.
The afternoon was passed in looking around the cave. All they found of interest were the bones of several wild animals.
"Perhaps they fell into this place and couldn't get out again," suggested Shep, gloomily.
Snap had obtained a long stick and with this he was poking at the ceiling in various spots. He worked with care, and the others watched him with interest.
"There, look at that!" he cried, presently. "The stick has gone through into something!"
He withdrew the stick as he concluded, and the boys saw a single ray of light shoot down upon them. All sprang to the opening quickly.