As the convict walked on, and Nic followed close behind, the splashing of their feet echoed softly from the walls, and the man’s voice sounded shut in and smothered. The air felt hot too, and oppressive, while the smouldering wood glowed and made the convict’s figure stand out like a solid carved block moving dimly outlined before Nic as he went on.

Then, all at once, the echoes of the disturbed water grew louder, and went whispering away; and as Leather went on talking his voice seemed to grow free, and the air was cool and damp.

“Now listen,” he said; and he paused, waved his smouldering torch, and uttered a loud cooey.

Nic caught at his arm, for there was a crash, and a bellowing roar as the cry went echoing away and then gradually died out in whispers.

“Startling, isn’t it? But only sound. The cavern is enormous here.”

“It’s dreadful!” panted Nic.

“No: wonderful and grand, boy. Ah! who knows what may be deeper down in the interior of this mighty world on which we crawl! Come along; you’ll have other chances of exploring here—that is, if you come to see me, Nic. Would you venture alone?”

“No,” said Nic frankly. “I don’t think I should dare.”

“Familiarity breeds contempt—even for darkness, Nic,” said the convict with a laugh, which sounded horrible. “Don’t be in a hurry to say that. I believe that with a lantern you would come. Forward, boy!”

“Is it much farther?”