level outcropping of igneous rock and sat staring at the nothing where the greenish-black sky met the pale gray horizon.

The tube was loosened on its shackles and presently fell, with a tinkling sound, upon the surface of Avis Solis. The opening was sealed and welded. Mr. Wordsley was practically finished, but he did not hurry. Instead, he went around to the opposite side of the ship on a pretense of inspection, and sat down where DeCastros could not see him.

For awhile he stared at the many-faceted depths of the crystals; then he leaned over and touched them with his lips. They were smooth and exciting. They cut his lip.

But he had the distinct feeling that there was something wrong with this idyll. It seemed to him that he was being spied upon. He sneaked a furtive glance behind him. DeCastros was still sitting where he had been, with his back to him.

Mr. Wordsley slowly lifted his gaze to the plateau of shimmering glass that was before him. At its rim, a hundred feet above him, a silent figure stood gazing down upon him.

A man even six feet tall might easily have frightened Mr. Wordsley into a nervous breakdown by staring at him with that gaunt, hollow-eyed stare, but this creature, though manlike, was fully fifty feet tall, incredibly elongated, and stark naked. Its hair was long and matted; its cheeks sunken, its lips pulled back in an expression which might have been anything from a smile to a cannibalistic snarl.

Mr. Wordsley cried out.

Captain DeCastros heard and came running across the intervening distance with swiftness incredible in one of his bulk at this gravity. His blizzer was out. It was one of the very latest models of blizzers. Very destructive. Mr. Wordsley had always been afraid to touch it.

He fired, and part of the plateau beneath the titan's feet fell away in a sparkling shower. The creature vanished.

DeCastros was red-faced and wheezing. "That was Malmsworth," he said. "Now how the devil do you suppose he managed to stick it out all these years!"

"If that was Malmsworth," Mr. Wordsley said, "he must be a very tall man."

"That was merely dimensional mirage. Come along. We'll have to hurry if we catch him."

"Why do we want to catch him?" Mr. Wordsley said.

Captain DeCastros made a sound of sober surprise. Even of pious wonder. "Malmsworth is my only brother," he said.

Mr. Wordsley wanted to say, "Yes, but you shot at him." He did not, because there was no time. He had to hurry to catch up with DeCastros, who was even now scrambling up the steep slope.

From the rim they could see Malmsworth out there on the flat. He was making good time, but Captain DeCastros proceeded to demonstrate that he was no mean hiker, himself. Mr. Wordsley's side began to hurt, and his breath came with difficulty. He might have died, if he had not feared to incur DeCastros' anger.

At times the naked man was a broad, flat monster upon that shimmering tableland. Again he seemed almost invisible; then gigantic and tenuous.

Presently he disappeared altogether.

"Oho!" DeCastros said, "If I am not mistaken, old Malmsworth has holed up in that very same rift where we caught him at his dirty business seventeen years ago. He's as mad as a Martian; you can lay to that. He'd have to be."

The rift, when they arrived at its upper reaches, was cool and shadowy. In its depths nothing sparkled. It was ordinary limestone. The walls were covered with a dull yellow moss, except for great, raw wounds where it had been torn off.

"That's Malmsworth's work," Captain DeCastros said. "In seventeen years, Mr. Wordsley, one will consume a lot of moss, I daresay. Shall we descend?"

The rift had reached its depth quite gradually, so that Mr. Wordsley scarcely realized that they were going down until the surface glare was suddenly gone, and the green-walled gloom surrounded them. It might have been a pleasant place, but Mr. Wordsley did not like it.

Captain DeCastros was taking his time now,