looked at him curiously.
"Are you waiting for me to tell you my price?"
"I'm waiting," said Allison reprovingly, "for you to agree not to cause me embarrassment. I won't be ungrateful. After all, I'm a person of some influence. I could do a great deal to your benefit. I'd be glad—"
"Are you working around to guess at a price I'll take?" asked Calhoun with the same air of curiosity.
He seemed much more curious than indignant, and much more amused than curious. Allison sweated suddenly. Calhoun didn't appear to be bribable. But Allison knew desperation.
"If you want to put it that way—yes," he said harshly. "You can name your own figure. I mean it!"
"I won't say a word about you," said Calhoun. "I won't need to. The characters who're operating your cattle fence will do all the talking that's necessary. Things all fit together,—except for one item. They've been dropping into place all the while we've been driving down this road."
"I said you can name your own figure!" Allison's voice was shrill. "I mean it! Any figure! Any!"
Calhoun shrugged.
"What would a Med Ship man do with money? Forget it!"
He drove on. The highway turnoff to Tenochitlan appeared. Calhoun went steadily past it. The other connection with the road through the town appeared. He left it behind.
Allison's teeth chattered again.
The buildings of Maya City began to appear, some twenty minutes later. Calhoun slowed and the other cars closed up. He opened a window and called:
"We want to go to the landing-grid first. Somebody lead the way!"
A car went past and guided the rest assuredly to a ramp down from the now-elevated road, and through utterly dark streets, of which some were narrow and winding, and came out abruptly where the landing-grid rose skyward. At the bottom its massive girders looked huge and cyclopean in the starlight, but the higher courses looked like silver lace against the stars.
* * * * *
They went to the control building. Calhoun got out. Murgatroyd hopped out after him, dust clinging to his fur. He shook himself, and a ten-thousand-credit interstellar credit certificate fell to the ground. Murgatroyd had made a soft place for sleeping out of the contents of Allison's attache case. It was assuredly the most expensive if not the most comfortable sleeping cushion a tormal ever had. Allison sat still as if numbed. He did not even pick up the certificate.
"I need you two electronics men," said Calhoun. Then he said apologetically to the others, "I only figured out something on the way here. I'd believed we might have to take some drastic action, come daybreak. But now I doubt it. I do suggest, though, that you turn off the car headlights and get set to do some shooting if anybody turns up. I don't know whether they will or not."
He led the way inside. He turned on lights. He went to the place where dials showed the amount of power actually being used of the enormous amount available. Those dials now showed an extremely small power drain, considering that the cities of a planet depended on the grid. But the cities were dark and empty of people. The demand needle wavered back and forth, rhythmically. Every two seconds the demand for power went up by six million kilowatts, approximately. The demand lasted for half a second, and stopped. For a second and a half the power in use was reduced by six million kilowatts. During this period only automatic pumps and ventilators and freezing equipment drew on the broadcast power for energy. Then the six-million-kilowatt demand came again for half a second.
"The cattle fence," said Calhoun, "works for half a second out of every two seconds. It's intermittent or it would simply paralyze animals that wandered into it. Or people. Being intermittent, it drives them out instead. There'll be tools and parts for equipment here, in case something needs repair. I want you to make something new."
The two electronics technicians asked questions.
"We need," said Calhoun, "an interruptor that will cut off the power broadcast for the half-second the ground-induction field is supposed to be on. Then it should turn on the broadcast power for the second and a half the cattle fence is supposed to be off. That will stop the cattle-fence effect, and I think a ground car should be able to work with power that's available for three half-seconds out of four."
The electronics men blinked at him. Then they grinned and set to work. Calhoun went exploring. He found a lunch box in a desk with three very stale sandwiches in it. He offered them around.
It appeared that nobody wanted to eat while their families—at the end of the highway—were still hungry.
The electronics men called on the two mechanics to help build something. They explained absorbedly to Calhoun that they were making a cutoff which would adjust to any sudden six-million-kilowatt demand, no matter what time interval was involved. A change in the tempo of the cattle-fence cycle wouldn't bring it back on.
"That's fine!" said Calhoun. "I wouldn't have thought of that!"
He bit into a stale sandwich and went outside. Allison sat limply, despairingly, in his seat in the car.
"The cattle fence is going off," said Calhoun without triumph. "The people of the city will probably begin to get here around sunrise."
"I—I did nothing legally wrong!" said Allison, dry-throated. "Nothing! They'd have to prove that I knew what the—consequences of the research project would be. That couldn't be proved! It couldn't! So I've done nothing legally wrong...."
Calhoun went inside, observing that the doctor who was also tennis champion, and the policeman who'd come to help him, were keeping keen eyes on the city and the foundations of the grid and all other places from which trouble might come.
There was a fine atmosphere of achievement in the power-control room. The power itself did not pass through these instruments, but relays here controlled buried massive conductors which supplied the world with power. And one of the relays had been modified. When the cattle-fence projector closed its circuit, the power went off. When the ground-inductor went off, the power went on. There was no longer a barrier across the highways leading to the east. It was more than probable that ground cars could run on current supplied for one and a half seconds out of every two. They might run jerkily, but they would run.
* * * * *
Half an hour later, the amount of power drawn from the broadcast began to rise smoothly and gradually. It could mean only that cars were beginning to move.
Forty-five minutes later still, Calhoun heard stirrings outside. He went out. The two men on guard gazed off into the city. Something moved there. It was a ground-car, running slowly and without lights. Calhoun said undisturbedly:
"Whoever was running the cattle fence found out their gadget wasn't working. Their lights flickered, too. They came to see what was the matter at the landing-grid. But they've seen the lighted windows. Got your blasters handy?"
But the unlighted car turned and raced away. Calhoun only shrugged.
"They haven't a prayer," he said. "We'll take over their apparatus as soon as it's light. It'll be too big to destroy, and there'll be fingerprints and such to identify them as the men who ran it. And they're not natives. When the police start to look for the strangers who were living where the cattle-fence projector was set up.... They can go into
