“Halt! Now, all together,” cried the captain from behind, and another series of shouts were given.

There was no response, and the party went spreading out and examining every nook as they passed through the echoing chambers, but found nothing.

“Is it likely that he did come out with us?” said Lennox as they neared the second well-like opening over the rushing water.

“Can’t say, sir,” said the sergeant. “The last I saw of him was when we were down in the lowest place, advancing to meet the second prisoner. I just had a squint of his face then by the lantern, and it looked like tallow.”

“Effect of the light,” said Dickenson.

“No, sir. It was the getting down that tree and hearing the water.”

“That’s it, sergeant,” said the nearest man behind. “I never thought of it till you said that.”

“Thought of what?” said the sergeant roughly.

“’Bout what Corporal May said to me.”

“What was it?”