Janus wet his lips and looked a little shamefaced. "I guess I'm kind of taut."
"That's what I taut," said Allenby.
The creature darted from behind its rock and, looking at us over its shoulder, employed six legs to make small but very fast tracks.
We turned our attention again to the desert. Far out, black against Mars' azure horizon, was a line of low hills.
"Shall we go look?" asked Burton, eyes gleaming at the mystery.
Janus hefted his gun nervously. It was still crackling faintly from the discharge. "I say let's get back to the ship!"
Allenby sighed. "My leg hurts." He studied the hills. "Give me the field-glasses."
Randolph handed them over. Allenby put them to the shield of his mask and adjusted them.
After a moment he sighed again. "There's a hole. On a plane surface that catches the Sun. A lousy damned round little impossible hole."
"Those hills," Burton observed, "must be thousands of feet thick."