"I don't know." Steve sat up and rubbed his head. "Y' know, Chief, it really felt more as though I'd just walked squarely into a solid stone wall."
"It has just occurred to me," Gerry said slowly, "that maybe that's exactly what you did do!"
Gerry walked forward cautiously, a foot at a time, one hand stretched out before him. When he reached a spot on line with the place where Steve had been stopped, his hand encountered something cool and firm and smooth. It was like the surface of a highly polished stone wall. Or a sheet of heavy and invisible glass. He ran both his hands over it. The thing was continuous and solid. There was nothing visible to the eye, and he could see far ahead of him across the strangely surfaced rocky plain, but there was an impenetrable barrier blocking the path.
Stepping back a few feet, Gerry picked up a pebble and tossed it upward. The stone bounced sharply back as soon as it came in line with the invisible barrier. He threw the pebble higher and the same thing happened. There was something mysterious and disquieting about the way the stone would soar up into the clear air—and then sharply bounce back from a point in space where nothing at all was visible.
"Magic!" Closana said nervously. Even the Earth-men of the landing party had drawn together in a compact group, ray-tubes ready and eyes alert.
Gerry moved back a few feet farther, then hurled the stone forward and upward as high as he could. This time the pebble did not bounce back. It simply vanished in thin air. And then, from somewhere off in the emptiness of space above them, there came the sound of a deep and mocking laughter!
As though that first laugh had somehow eased the necessity for a carefully enforced silence, there came a whole burst of unseen and eerie merriment. There was a murmur of many voices. Then it died away again. There was still nothing visible, and the silence was once more unbroken.
"For Lord's sake, let's get out of here!" Portok gasped. "This place is ghost ridden!"
"There are no ghosts here, little red-faced man!" boomed a voice.