So the next morning he overhauled his suit and patched it. He got fresh oxygen and bought a meager supply of food. He had one more good meal and started out south again with the single stone in his watch-pocket.

It took him seven hours to reach the place where he had left the constrictor. It was gone, of course. How far, he could not know. He took the one telepathic stone from his pocket. He found a spot where he could sit in the open, cross-legged, with his eyes fixed on the stone. From the corner of his eye he saw a brown detached eye on a stalk pop up from the surface of the water, but he paid no attention. He concentrated on the stone.

The stone had a fair polish. He looked at its surface and shut out all the normal sounds from his ears. The stone seemed to be in motion on the inside, and presently that motion communicated itself to his mind. He had a picture of a constrictor, lying sleepily in a pool of brown water surrounded by heavy, deep grass that hung over the banks and grew down into the water.

He heard now the distant bellow of a swamp-ox, the buzzing of aquatic bees. Slowly he turned the stone on its edge and revolved it carefully. When the picture was clearest in his mind he picked out an orientation point in the distant mountains. Then, well pleased, he put the stone in his pocket, got into his diving-suit, screwed on the helmet, adjusted the oxygen, and stepped off into the brown water of the swamp.

The bottom here was steep but it was good. It was hard and not more than knee-deep in mud. He traveled carefully, freezing on occasion when huge shadows moved above him. He was in fifty feet of water and he liked that better because it was easier to go unnoticed. He avoided a patch of electric cactus, for the spines would have electrocuted him even through the suit, and he went far around an area of white bull-root,