“Never, sir. It’s all natural rock. Look at the crystals.”

“That’s what I thought. But look up there at Joe.”

“Eh? Where’s Mr Joe Jollivet?”

“Clambering up that hole where Grip must have gone. He must have got up to the surface.”

Hardock shook his head.

“Why not?” continued Gwyn, eagerly. “The wind rushes up there.”

“Ay, but wind will go where even a mouse couldn’t.”

“But if Grip hadn’t got up there, he’d have come back.”

“If he could, sir—if he could. But don’t, don’t ask me questions; I’m all mazed like, and can’t think or do anything. I only want to go to sleep, sir, out of it all, never to have any more of this horror and trouble.”

“Look here, Sam,” continued Gwyn; “this noise of the wind coming up means the water filling up the passages and driving it out, doesn’t it?”