Then it rolled forward again, but more cautiously. It stopped again, at the same place. It tried again, a few yards to one side.
There was a barrier there of some sort. It clicked, then, in Carson’s mind, that thought projected by the Entity who had brought them there:
“—accident of physical strength will not completely decide the issue. There is a barrier.”
A force-field, of course. Not the Netzian Field, known to Earth science, for that glowed and emitted a crackling sound. This one was invisible, silent.
It was a wall that ran from side to side of the inverted hemisphere; Carson didn’t have to verify that himself. The Roller was doing that, rolling sideways along the barrier, seeking a break in it that wasn’t there.
Carson took half a dozen steps forward, his left hand groping out before him, and touched the barrier. It felt smooth, yielding, like a sheet of rubber rather than like glass, warm to his touch, but no warmer than the sand underfoot. And it was completely invisible, even at close range.
He dropped the stone and put both hands against it, pushing. It seemed to yield, just a trifle, but no farther than that trifle, even when he pushed with all his weight. It felt like a sheet of rubber backed up by steel. Limited resiliency, and then firm strength.
He stood on tiptoe and reached as high as he could and the barrier was still there.
He saw the Roller coming back, having reached one side of the arena. That feeling of nausea hit Carson again, and he stepped back from the barrier as it went by. It didn’t stop.
But did the barrier stop at ground-level? Carson knelt down and burrowed in the sand; it was soft, light, easy to dig in. And two feet down the barrier was still there.
The Roller was coming back again. Obviously, it couldn’t find a way through at either side. There must be a way through, Carson thought, or else this duel is meaningless.
The Roller was back now, and it stopped just across the barrier, only six feet away. It seemed to be studying him although, for the life of him, Carson couldn’t find external evidence of sense organs on the thing. Nothing that looked like eyes or ears, or even a mouth. There was though, he observed, a series of grooves, perhaps a dozen of them altogether, and he saw two tentacles push out from two of the grooves and dip into the sand as though testing its consistency. These were about an inch in diameter and perhaps a foot and a half long.
The tentacles were retractable into the grooves and were kept there except when in use. They retracted when the thing rolled and seemed to have nothing to do with its method of locomotion; that, as far as Carson could judge, seemed to be accomplished by some shifting—just how he couldn’t imagine—of its center of gravity.
He shuddered as he looked at the thing. It was alien, horribly different from anything on Earth or any of the life forms found on the other solar planets. Instinctively, he knew its mind was as alien as its body.
If it could project that almost tangible wave of hatred, perhaps it could read his mind as well, sufficiently for his purpose.
Deliberately, Carson picked up the rock that had been his only weapon, then tossed it down again in a gesture of relinquishment and raised his empty hands, palms up, before him.
He spoke aloud, knowing that although the words would be meaningless to the creature before him, speaking them would focus his own thoughts more completely upon the message.
“Can we not have peace between us?” he said, his voice strange in the stillness. “The Entity who brought us here has told us what must happen if our races fight—extinction of one and weakening and retrogression of the other. The battle between them, said the Entity, depends upon what we do here. Why cannot we agree to an eternal peace—your race to its galaxy, we to ours?”
Carson blanked out his mind to receive a reply.
It came, and it staggered him back, physically. He recoiled several steps in sheer horror at the intensity of the lust-to-kill of the red images projected at him. For a moment that seemed eternity, he had to struggle against the impact of that hatred, fighting to clear his mind of it and drive out the alien thoughts to which he had given admittance. He wanted to retch.
His mind cleared slowly. He was breathing hard and he felt weaker, but he could think.
He stood studying the Roller. It had been motionless during the mental duel it had so nearly won. Now it rolled a few feet to one side, to the nearest of the blue bushes. Three tentacles whipped out of their grooves and began to investigate the bush.
“O.K.,” Carson said, “so it’s war then.” He managed a grin. “If I got your answer straight, peace doesn’t appeal to you.” And, because he was, after all, a young man and couldn’t resist the impulse to be dramatic, he added, “To the death!”
But his voice, in that utter silence, sounded silly even to himself. It came to him, then, that this was to the death, not only his own death or that of the red spherical thing which he thought of as the Roller, but death to the entire race of one or the other of them: the end of the human race, if he failed.
It made him suddenly very humble and very afraid to think that. With a knowledge that was above even faith, he knew that the Entity who had arranged this duel had told the truth about its intentions and its powers. The future of humanity depended upon him. It was an awful thing to realize. He had to concentrate on the situation at hand.
There had to be some way of getting through the barrier, or of killing through the barrier.
Mentally? He hoped that wasn’t all, for the Roller obviously had stronger telepathic powers than the undeveloped ones of the human race. Or did it?
He had been able to drive the thoughts of the Roller out of his own mind; could it drive out his? If its ability to project were stronger, might not its receptivity mechanism be more vulnerable?
He stared at it and endeavored to concentrate and focus all his thought upon it.
“Die,” he thought. “You are going to die. You are dying. You are—”
He tried variations on it, and mental pictures. Sweat stood out on his forehead and he found himself trembling with the intensity of the effort. But the Roller went ahead with its investigation of the bush, as utterly unaffected as though Carson had been reciting the multiplication table.
So that was no good.
He felt dizzy from the heat and his strenuous effort at concentration. He sat down on the blue sand and gave his full attention to studying the Roller. By study, perhaps, he could judge its strength and detect its weaknesses, learn things that would be valuable to know when and if they should come to grips.
It was breaking off twigs. Carson watched carefully, trying to judge just how hard it worked to do that. Later, he thought, he could find a similar bush on his own side, break off twigs of equal thickness himself, and gain a comparison of physical strength between his own arms and hands and those tentacles.
The twigs broke off hard; the Roller was having to struggle with each one. Each tentacle, he saw, bifurcated at the tip into two fingers, each tipped by a nail or claw. The claws didn’t seem to be particularly long or dangerous, or no more so than his own fingernails, if they were left to grow a bit.
No, on the whole, it didn’t look too hard to handle physically. Unless, of course, that bush was made of pretty tough stuff. Carson looked round; within reach was another bush of identically the same type.
He snapped off a twig. It was brittle, easy to break. Of course, the Roller might have been faking deliberately, but he didn’t think so. On the other hand, where was it vulnerable? How would he go about killing it if he got the chance? He went back to studying it. The outer hide looked pretty tough; he’d need a sharp weapon of some sort. He picked up the piece of rock again. It was about twelve inches long, narrow, and fairly sharp on one end. If it chipped like flint, he could make a serviceable knife out of it.