"Yes, sure!" said Peer impatiently. "They're cute! They're all lined with glass or something." She spread her arms wide. "Jump, and I'll catch you!"
Channok laughed, flopped over on his stomach with his legs over the edge of the rock, and slid down in a fair imitation of Peer's nonchalant style of descent, spraining his ankle only a little. Well, he hadn't grown up skipping from craggy moon to asteroid to heavy-planet to whatnot like she had....
They threaded their way about the rocks to the spot she had been studying. She explained that he'd have to climb into the burrow to get a good idea of what it was like.
"Well, look now, Peer!" Channok protested, staring into the big, round hole that slanted downwards under a big boulder—it did seem to be lined with black glass or some similar stuff. "That cave's got 'No Trespassing' written all over it. Supposing I slide down a half a mile and land in a mess of ghouls!"
"No, you won't," Peer said hurriedly. "It goes level right away, and they're never more than thirty feet long. And the ghoul's out—there's never more than one to a burrow; and I saw this one pop out and run off just before we started here! You're not scared, are you? Wilf and I crawled in and out of hundreds of them!"
"Well, just for a moment then," said Channok resignedly.
He got down on hands and knees and crept into the tunnel. After about six feet, he stopped and found he could turn around without too much trouble. "Peer?" he called back.
"Yes?" said Peer.
"How can I see anything here," Channok demanded peevishly, "when it's all dark?"