"Mr. Kjerulf, what is a velocity shift damper?"
Kjerulf looked startled. Jerryberry said, "I took journalism."
"Ah."
"It's not just curiosity. My dad lost a fortune on airline stock-"
"So did I," said Kjerulf, half-smiling with old pain.
"Oh?"
"Sometimes I feel I've sold out. The booths couldn't possibly compete with the airlines, could they? They wouldn't send far enough. Yet they ruined us."
"My dad figured the same way."
"And now the booths do send that far, and I'm working for them, or they're working for me. There wasn't all that much reason to build the long-distance systems at airports. Lots of room here, of course, and an organization already set up. . but they really did it to save the airline companies."
"A little late."
"Perhaps. Some day they'll turn us into a public utility." Kjerulf looked about the room, then called to a man seated near the flat wall of the semicircle. "Dan!"
"Yo!" the man boomed without looking up.
"Can you spare me twenty minutes for a public-relations job?"
The man stood up, then climbed up on his chair. He looked slowly about the room. Jerryberry guessed that he could see every instrument board from where he was standing. He called, "Sure. No sweat."
They took the cart back to the terminal. They entered a booth. Jerryberry inserted his C. B. A. credit card, then waited while Kjerulf dialed.
They were in a concrete building. Beyond large square windows a sunlit sea of blue water heaved and splashed, almost at floor level. Men looked around curiously, recognized Nils Kjerulf, and turned back to their work.
"Lake Michigan. And out there-" Kjerulf pointed. Jerryberry saw a tremendous white mass, a flattened dome, very regular. A great softly rounded island. "-is the United Air Lines velocity damper. All of the dampers look about like that, but they float in different lakes or oceans. Aeroflot uses the Caspian Sea. The T.W.A. damper is in the Gulf of Mexico."
"Just what is it?"
"Essentially it's a hell of a lot of soft iron surrounded by a hell of a lot more foam plastic, enough to float it, plus a displacement-booth receiver feeding into the iron. Look, see it surge?"
The island rose several feet, slowly, then fell back as slowly. Ripples moved outward and became waves as they reached the station.
"That must have been a big load. Now, here's how it works. You know that the rotation of the Earth puts a limit on how far you can send a load. If you were to shift from here to Rio de Janeiro, say, you'd flick in moving up and sideways-mainly up, because Rio and L.A. are almost the same distance from the equator.
"But with the long-distance booths, the receiver picks up the kinetic energy and shunts it to the United Air Lines velocity damper. That big mass of iron surges up or down or sideways until the water stops it-or someone flicks in from Rio and the damping body stops cold."
Jerryberry thought about it. "What about conservation of rotation? It sounds like you're slowing down the Earth."
"We are. There's nothing sacred about conservation of rotation, except that the energy has to go somewhere. There are pumps to send water through the damper bodies if they get too hot."
Jerryberry pulled out the Minox. "Mind if I take some pictures?"
"No, go ahead."
The Minox was a movie camera, but it would not have the resolution of a press camera. No matter. If he had the time he could comeback. . not that he thought he would. He took shots of the men at work in the station, of Nils Kjerulf with his back to the windows. He shot almost a minute of the great white island itself. He was hoping it would surge; and presently it did, sinking sideways, surging up again. Waves beat at the station. A jet of white steam sprayed from the top of the great white mass.
"Good," he said briskly to himself. He folded the spidery tripod legs and dropped the camera in his pocket. He turned to Kjerulf, who had been watching the proceedings with some amusement. "Mr. Kjerulf, can you tell me anything about traffic control? Is there any?"
"How do you mean? Customs?"
"Not exactly.. but tell me about customs."
"The customs terminal in Los Angeles is at T.W.A. You haven't been out of the country recently? No? Well, any big-city airport has a customs terminal. In a small country there's likely to be just one. If you dial a number outside the country, any country, you wind up in somebody's customs terminal. The booths there don't have dials, you see. You have to cross the customs line to dial out."
"Clever. Are there any restrictions on traffic within the United States?"
"No, you just drop your chocolate dollars in and dial. Unless it's a police matter. If the police know that someone's trying to leave the city they may set up a watch in the terminals. We can put a delay on the terminals to give a detective time to look at a passenger's face and see if he's who they want."
"But nothing to stop passengers from coming in."
"No, except that it's possible to Kjerulf trailed off oddly, then finished, "…turn off any booth by remote control, from the nearest JumpShift maintenance system. What are you thinking of, the mall riot?"
There was no more to say. He left Nils Kjerulf in the United terminal in Los Angeles. He dialed for customs.
For several minutes Jerryberry watched them flicking in. There were two types:
The tourists came in couples, sometimes with a child or two. They flicked in looking interested and harried and a little frightened. Their clothing was outlandish and extraordinary. Before they left the booths, they would look about them mistrustfully. Sometimes they formed larger groups.
The businessmen traveled alone. They wore conservative or old-fashioned clothing and carried one suitcase: large or small, but one. They were older than the tourists. They moved with authority, walking straight out of the booths the moment they appeared.
At the barner: four men in identical dark suits with shield-shaped shoulder patches. Jerryberry was on the wrong side of the barrier to command their attention. He was thinking of dialing himself to Mexico and back when one of them noticed him and pegged him as a newstaper.
His name was Gregory Scheffer. Small and round and middle-aged, he perched on the wooden barner and clasped one knee in both hands. "Sure, I can talk awhile. This isn't one of the busy days. The only time these booths really get a workout is Christmas and New Year and Bastille Day and like that. Look around you," he said, waving a pudgy hand expansively.
"About four times as many incoming as there was six months ago. I used to want to search every bag that came through, just to be doing something. If we keep getting more and more of them this way, we'll need twice as many customs people next year."
"Why do you suppose-"
"Did you know that the long-distance booths have been operating for two solid years? It's only in the last six months or so that we've started to get so many passengers. They had to get used to traveling again. Look around you; look at all this space. It used to be full before JumpShift came along. People have got out of the habit of traveling, that's all there is to it. For twenty solid years. They have to get back into it."
"Guess so." Jerryberry tried to remember why he was here. "Mr. Scheffer-"