“Shall we go inside?” asked Jack presently.
“We might as well now as at any other time,” said the professor, “Ralph, will you and Walter go back to the camp and get the torches?”
The lads at once hastened off on their errand. Truth to tell, they were each rather glad to get, for a short time only, out of the spell of that somber spot.
The torches referred to were of the kerosene variety, but specially made to burn for twenty-four hours continuously. They had been made to the professor’s order for the expedition.
The boys returned shortly with the illuminants. Ralph also brought a supply of matches and a canteen of water, and both boys had stuffed their pockets full of what food they could hastily get together. The professor praised their foresight and then, from his own pocket, produced a huge spool of coarse, strong thread.
“I took the hint from the classics,” he said, “you all recollect the tale of the labyrinth? Well, we will make this thread fast at the entrance, and as we go along we will unwind it. In that way if we get lost we can find our way back by feeling along the thread.”
“That’s a splendid idea,” cried Jack, “I tell you I shouldn’t much fancy the idea of going in there, unless I was pretty sure how I was going to get out again.”
“I don’t blame you,” said the professor, “and now are we all ready?”
“All right!” came in a chorus, and led by the man of science, the adventurers crossed the mystic threshold. A thrill shot through even Coyote Pete, the least impressible of the party, as they did so. How long had it been since the race of ancient dwellers of the Chinipal had swarmed those subterranean corridors, now as silent as midnight?