only the outer rind and mask of some subterranean world? And if so, what sort of world? What sort of inhabitants might it not presently disgorge upon us?
And then, stabbing the aching stillness as vivid and sudden as an unexpected thunderclap, came a clang and rattle as though great gates of metal had suddenly been flung apart.
It arrested our steps. We stood gaping helplessly. Then Cavor stole towards me.
"I do not understand!" he whispered close to my face. He waved his hand vaguely skyward, the vague suggestion of still vaguer thoughts.
"A hiding-place! If anything came . . ."
I looked about us. I nodded my head in assent to him.
We started off, moving stealthily with the most exaggerated precautions against noise. We went towards a thicket of scrub. A clangour like hammers flung about a boiler hastened our steps. "We must crawl," whispered Cavor.
The lower leaves of the bayonet plants, already overshadowed by the newer ones above, were beginning to wilt and shrivel so that we could thrust our way in among the thickening stems without serious injury. A
