The Ork sat upon its haunches much as a cat does, but used the finger-like claws of its front legs almost as cleverly as if they were hands. Perhaps the most curious thing about the creature was its tail, or what ought to have been its tail. This queer arrangement of skin, bones and muscle was shaped like the propellers used on boats and airships, having fan-like surfaces and being pivoted to its body. Cap'n Bill knew something of mechanics, and observing the propeller-like tail of the Ork he said:

"I s'pose you're a pretty swift flyer?"

"Yes, indeed; the Orks are admitted to be Kings of the Air."

"Your wings don't seem to amount to much," remarked Trot.

"Well, they are not very big," admitted the Ork, waving the four hollow skins gently to and fro, "but they serve to support my body in the air while I speed along by means of my tail. Still, taken altogether, I'm very handsomely formed, don't you think?"

Trot did not like to reply, but Cap'n Bill nodded gravely. "For an Ork," said he, "you're a wonder. I've never seen one afore, but I can imagine you're as good as any."

That seemed to please the creature and it began walking around the cavern, making its way easily up the slope. While it was gone, Trot and Cap'n Bill each took another sip from the water-flask, to wash down their breakfast.

"Why, here's a hole—an exit—an outlet!" exclaimed the Ork from above.

"We know," said Trot. "We found it last night."

"Well, then, let's be off," continued the Ork, after sticking its head into the black hole and sniffing once or twice. "The air seems fresh and sweet, and it can't lead us to any worse place than this."

The girl and the sailor-man got up and climbed to the side of the Ork.

"We'd about decided to explore this hole before you came," explained Cap'n Bill; "but it's a dangerous place to navigate in the dark, so wait till I light a candle."

"What is a candle?" inquired the Ork.

"You'll see in a minute," said Trot.

The old sailor drew one of the candles from his right-side pocket and the tin matchbox from his left-side pocket. When he lighted the match the Ork gave a startled jump and eyed the flame suspiciously; but Cap'n Bill proceeded to light the candle and the action interested the Ork very much.

"Light," it said, somewhat nervously, "is valuable in a hole of this sort. The candle is not dangerous, I hope?"

"Sometimes it burns your fingers," answered Trot, "but that's about the worst it can do—'cept to blow out when you don't want it to."

Cap'n Bill shielded the flame with his hand and crept into the hole. It wasn't any too big for a grown man, but after he had crawled a few feet it grew larger. Trot came close behind him and then the Ork followed.