He felt Murgatroyd's pulse, and timed it with his sweep-second watch. He timed the muscular spasms that Murgatroyd displayed. They coincided with disturbances in his heart-beat. They came at approximately two-second intervals, and the tautening of the muscles lasted just about half a second.
"But I don't feel it!" said Calhoun.
Murgatroyd whimpered again and said, "Chee-chee!"
"What's going on?" demanded Allison, with the impatience of a very important man indeed. "If the beast's sick, he's sick! I've got to find—"
Calhoun opened his med kit and went carefully through it. He found what he needed. He put a pill into Murgatroyd's mouth.
"Swallow it!" he commanded.
Murgatroyd resisted, but the pill went down. Calhoun watched him sharply. Murgatroyd's digestive system was delicate, but it was dependable. Anything that might be poisonous, Murgatroyd's stomach rejected instantly. But the pill stayed down.
"Look!" said Allison indignantly. "I've got business to do! In this attaché-case I have some millions of interstellar credits, in cash, to pay down on purchases of land and factories! I ought to make some damned good deals! And I figure that that's as important as anything else you can think of! It's a damned sight more important than a beast with a belly-ache!"
Calhoun looked at him coldly.
"Do you own land on Texia?" he asked.
Allison's mouth dropped open. Extreme suspicion and unease appeared on his face. As a sign of the unease, his hand went to the side coat pocket in which he'd put a blaster. He didn't pluck it out. Calhoun's left fist swung around and landed. He took Allison's elaborate pocket-blaster and threw it away among the monotonous rows of olive-green plants. He returned to absorbed observation of Murgatroyd.
In five minutes the muscular spasms diminished. In ten, Murgatroyd frisked. But he seemed to think that Calhoun had done something remarkable. In the warmest of tones he said:
"Chee!"
"Very good," said Calhoun. "We'll go ahead. I suspect you'll do as well as we do—for a while."
The car lifted the few inches the air-columns sustained it above the ground. It went on, still to the eastward. But Calhoun drove more slowly, now.
"Something was giving Murgatroyd rhythmic muscular spasms," he said coldly. "I gave him medication to stop them. He's more sensitive than we are so he reacted to a stimulus we haven't noticed yet. But I think we'll notice it presently."
Allison seemed to be dazed at the affront given him. It appeared to be unthinkable that anybody might lay hands on him.
"What the devil has that to do with me?" he demanded angrily. "And what did you hit me for? You're going to pay for this!"
"Until I do," Calhoun told him, "you'll be quiet. And it does have the devil to do with you. There was a Med Service gadget, once—a tricky little device to produce contraction of chosen muscles. It was useful for restarting stopped hearts without the need of an operation. It regulated the beat of hearts that were too slow or dangerously irregular. But some business man had a bright idea and got a tame researcher to link that gadget to ground induction currents. I suspect you know that business man!"
"I don't know what you're talking about," snapped Allison. But he was singularly tense.
"I do," said Calhoun unpleasantly. "I made a public-health inspection on Texia a couple of years ago. The whole planet is a single, gigantic, cattle-raising enterprise. They don't use metal fences. The herds are too big to be stopped by such things. They don't use cowboys. They cost money. On Texia they use ground-induction and the Med Service gadget linked together to serve as cattle fences. They act like fences, though they're projected through the ground. Cattle become uncomfortable when they try to cross them. So they draw back. So men control them. They move them from place to place by changing the cattle-fences which are currents induced in the ground. The cattle have to keep moving or be punished by the moving fence. They're even driven into the slaughterhouse chutes by ground-induction fields! That's the trick on Texia, where induction fields herd cattle. I think it's the trick on Maya, where people are herded like cattle and driven out of their cities so the value of their fields and factories will drop—so a land-buyer can find bargains!"
"You're insane!" snapped Allison. "I just landed on this planet. You saw me land! I don't know what happened before I got here. How could I?"
"You might have arranged it," said Calhoun.
Allison assumed an air of offended and superior dignity. Calhoun drove the car onward at very much less than the headlong pace he'd been keeping to. Presently he looked down at his hands on the steering-wheel. Now and then the tendons to his fingers seemed to twitch. At rhythmic intervals, the skin crawled on the back of his hands. He glanced at Allison. Allison's hands were tightly clenched.
"There's a ground-induction fence in action, all right," said Calhoun calmly. "You notice? It's a cattle-fence and we're running into it. If we were cattle, now, we'd turn around and move away."
"I don't know what you're talking about!" said Allison
But his hands stayed clenched. Calhoun slowed the car still more. He began to feel, all over his body, that every muscle tended to twitch at the same time. It was a horrible sensation. His heart-muscles tended to contract too, simultaneously with the rest, but one's heart has its own beat-rate. Sometimes the normal beat coincided with the twitch. Then his heart pounded violently—so violently that it was painful. But equally often the imposed contraction of the heart-muscles came just after a normal contraction, and then it stayed tightly knotted for half a second. It missed a beat, and the feeling was agony. No animal would have pressed forward in the face of such sensations. It would have turned back long ago.
Calhoun stopped the car. He looked at Murgatroyd. Murgatroyd was completely himself. He looked inquiringly at Calhoun. Calhoun nodded to him, but he spoke—with some difficulty—to Allison.
"We'll see—if this thing—builds up. You know that it's the Texia—trick. A ground—induction unit set up—here. It drove people—like cattle. Now we've—run into it. It's holding people—like cattle."
He panted. His chest-muscles contracted with the rest, so that his breathing was interfered with. But Murgatroyd, who'd been made uneasy and uncomfortable before Calhoun noticed anything wrong, was now bright and frisky. Medication had desensitized his muscles to outside stimuli. He would be able to take a considerable electric shock without responding to it. But he could be killed by one that was strong enough.
A savage anger filled Calhoun. Everything fitted together. Allison had put his hand convenient to his blaster when Calhoun mentioned Texia. It meant that Calhoun suspected what Allison knew to be true. A cattle-fence unit had been set up on Maya, and it was holding—like cattle—the people it had previously driven like cattle. Calhoun could even deduce with some precision exactly what had been done. The first experience of Maya with the cattle-fence would have been with a very mild version of it. It would have been low-power and cause just enough uneasiness to be noticed. It would have been moved from west to east, slowly, and it would have reached a certain spot and there faded out. And it would have been a mystery and an uncomfortable thing, and nobody would understand it on Maya. In a week it would almost be forgotten. But then there'd come a stronger disturbance. And it would travel like the first one; down the length of the peninsula on which the colony lay, but stopping at the same spot as before, and then fading away to nothingness. And this also would have seemed mysterious but nobody would suspect humans of causing it. There'd be theorizing and much questioning, but it would be considered an unfamiliar natural event.
Probably the third use of the cattle-fence would be most disturbing. This time it would be acutely painful. But it would move into the cities and through them and past them—and it would go down the peninsula to where it had stopped and faded on two previous occasions. And the people of Maya would be disturbed and scared. But they considered that they knew it began to the westward of Maya City, and moved toward the east at such-and-such a speed, and it went so far and no farther. And they would organize themselves to apply this carefully-worked-out information. And it would not occur to any of them that they had learned how to be driven like cattle.