My chest hit something hard, and I found myself with my chin on the edge of an unfathomable abyss that had suddenly opened beneath me, my hand extended stiffly into the void. The whole of that flat circular area was no more than a gigantic lid, that was now sliding sideways from off the pit it had covered into a slot prepared for it.
Had it not been for Cavor I think I should have remained rigid, hanging over this margin and staring into the enormous gulf below, until at last the edges of the slot scraped me off and hurled me into its depths. But Cavor had not received the shock that had paralysed me. He had been a little distance from the edge when the lid had first opened, and perceiving the peril that held me helpless, gripped my legs and pulled me backward. I came into a sitting position, crawled away from the edge for a space on all fours, then staggered up and ran after him across the thundering, quivering sheet of metal. It seemed to be swinging open with a steadily accelerated velocity, and the bushes in front of me shifted sideways as I ran.
I was none too soon. Cavor's back vanished amidst the bristling thicket, and as I scrambled up after him, the monstrous valve came into