This was easier said than done. They went on once more, and soon, without warning, stepped into water up to their knees.
"Back!" cried Dick, who was in advance. "We don't want to get drowned.
That would be as bad as being burnt up."
"We can swim," answered Tom as he scrambled back.
"True, but I want to know where I am swimming to, don't you?"
Tom got out his waterproof match safe and found that it contained just one match. This was lit, and then he set fire to some leaves from a notebook in his pocket. By this light, they saw another turn of the passageway, leading upward.
"That must be a way out," exclaimed Tom, and started in the direction, followed by his brother.
"Now, go slow," warned Dick when they were once more in darkness, the paper having burnt itself out. "We don't want to run into any more danger, if we can avoid it."
"I am on my guard," answered Tom.
They soon found that the side passage narrowed greatly, so that they had to proceed in single file and with heads bent. They moved with their hands in front of their heads, so as to avoid a possible collision with the rocks along the way.
Presently Dick's hand came in contact with something long and straggling. He drew back, thinking he had touched a snake. But then he grew bolder and found it to be a tree root.