“Snake, or wild-cat,” he said.

“Eh?” said Mr. Hume, waking at once.

There was a ring of metal, a sudden babel of fierce cries, the flash of a rifle-shot, and the clap of the report, followed by shrieks.

“It’s all right, lad,” shouted Mr. Hume, as Venning straggled to rise; “keep down.”

There was a sharp hissing.  Something struck the rock above the Hunter as he was stooping over Venning, and fell down into the fire.  It was a barbed arrow.  He fired again, scattered the fire with a kick, and crouched over the boy.  Several arrows rang viciously against the rock.  He felt for Venning’s carbine, swung it round with one hand, and emptied the magazine, firing at different points.  With yells of disappointment, rage, and fear, the creatures of the night fled once more.

“Are you all right, my boy?”

“Yes; but what does it mean?  What were they?  I thought the thing was a snake.”

“What did you see?”

“Something staring out of the shadows.  I could not make out what it was, and as you awoke it seemed to jump forward and strike.”

“Ay, the blow fell on my belt.  Thank God, you warned me; but it was my fault.  I should have kept awake.  They’re only women, lad.  Don’t let any fancies come into your head.”

Venning sniffed.  “Smell anything?  Seems to me like sulphur.”

“It’s the gunpowder fumes, hanging low.”

Venning sat up.  “What is that booming noise?”

“The sound of falling water.”

The boy was silent for some time, while the Hunter reloaded the carbine and his Express.

“So—–­we are still down below.”

“But I know the way out, and as soon as it is daylight we’ll get back into the valley.  Have no fears.”

Venning’s hand went out to feel for his companion.  “I must have given you a lot of trouble.  You’ve got your coat off.”

“I didn’t want it, and it came in handy as a pillow.”

“Put it on,” said Venning, “and give me my gun.”

Mr. Hume laughed cheerily.  “Feeling yourself again—­eh?  Well, that’s good.  And now we’ll put an end to this nonsense.”

“I certainly smell sulphur,” said Venning; “and what is that blue streak there?” He took a step towards the smooth cone.  “It is sulphur!” he cried.  “See, it’s burning.”

Mr. Hume stepped to his side, and saw the unmistakable blue flame given off by burning sulphur, while a whiff of the fumes made him choke.

“You’re right; it’s a mass of sulphur.  The burning wad front the cartridge must have set it alight.”  He sliced off the burning patch with his knife.  “We don’t want to be fumigated, or to die of suffocation.  Now, if you feel strong enough, we’ll explore the cave.”

“Is it safe?  I mean, are there any chasms?”

“Smooth as a floor.  Keep close by me.”

They examined the cavern carefully by means of the strange lantern filled with fungus, and Mr. Hume halted by the second exit.