The Fountains of Paradise

by Arthur C. Clarke

  “Global communications, weather forecasting and control, land and ocean resources, banks, postal and information services—if anything happened to their spaceborne systems, we would sink back into a dark age. During the resultant chaos, disease and starvation would destroy much of the human race.

  “And looking beyond the Earth, now that we have self-sustaining colonies on Mars, Mercury, and the moon, and are mining the incalculable wealth of the asteroids, we see the beginnings of true interplanetary commerce. Though it took a little longer than the optimists predicted, it is now obvious that the conquest of the air was only a modest prelude to the conquest of space.

  “But now we are faced with a fundamental problem, an obstacle that stands in the way of all future progress. Although the research work of generations has made the rocket the most reliable form of propulsion ever invented . . .”

  “Has he considered bicycles?” muttered Sarath.

  “. . . space vehicles are still grossly inefficient. Even worse, their effect on the environment is appalling. Despite all attempts to control approach corridors, the noise of take-off and re-entry disturbs millions of people. Exhaust products dumped in the upper atmosphere have triggered climatic changes, which may have very serious results. Everyone remembers the skin-cancer crisis of the twenties, caused by ultraviolet breakthrough—and the astronomical cost of the chemicals needed to restore the ozonosphere.

  “Yet if we project traffic growth to the end of the century, we find that earth-to-orbit tonnage must be increased almost fifty percent. This cannot be achieved without intolerable costs to our way of life—perhaps to our very existence. And there is nothing that the rocket engineers can do. They have almost reached the absolute limits of performance, set by the laws of physics.

  “What is the alternative? For centuries, men have dreamed of antigravity and of ‘spacedrives.’ No one has ever found the slightest hint that such things are possible; today we believe that they are only fantasy.

  “In the very decade that the first satellite was launched, however, one daring Russian engineer conceived a system that would make the rocket obsolete. It was years before anyone took Yuri Artsutanov seriously. It has taken two centuries for our technology to match his vision.”

  Each time he played the recording, it seemed to Rajasinghe that Morgan really came alive at this point. It was easy to see why; now he was on his own territory, no longer relaying information from an alien field of expertise. And despite all his reservations and fears, Rajasinghe could not help sharing some of that enthusiasm. It was a quality that, nowadays, seldom impinged upon his life.

  “Go out of doors any clear night,” continued Morgan, “and you will see that commonplace wonder of our age—the stars that never rise or set, but are fixed motionless in the sky. We, and our parents, and their parents have long taken for granted the synchronous satellites and space stations, which move above the equator at the same speed as the turning earth, and so hang forever above the same spot.

  “The question Artsutanov asked himself had the childlike brilliance of true genius. A merely clever man could never have thought of it—or would have dismissed it instantly as absurd.

  “If the laws of celestial mechanics make it possible for an object to stay fixed in the sky, might it not be possible to lower a cable down to the surface, and so to establish an elevator system linking earth to space?

  “There was nothing wrong with the theory, but the practical problems were enormous. Calculations showed that no existing materials would be strong enough. The finest steel would snap under its own weight long before it could span the thirty-six thousand kilometers between earth and synchronous orbit.

  “However, even the best steels were nowhere near the theoretical limits of strength. On a microscopic scale, materials had been created in the laboratory with far greater breaking strength. If they could be mass-produced, Artsutanov’s dream could become reality—and the economics of space transportation would be utterly transformed.

  “Before the end of the twentieth century, super-strength materials—hyperfilaments—had begun to emerge from the laboratory. But they were extremely expensive, costing many times their weight in gold. Millions of tons would be needed to build a system that could carry all earth’s outbound traffic. So the dream remained a dream—until a few months ago.

  “Now the deep-space factories can manufacture virtually unlimited quantities of hyperfilament. At last we can build the Space Elevator—or the Orbital Tower, as I prefer to call it. In a sense it is a tower, rising clear through the atmosphere, and far, far beyond. . . .”

  Morgan faded out, like a ghost that had been suddenly exorcised. He was replaced by a football-sized Earth, slowly revolving. Moving an arm’s breadth above it, and keeping always poised above the same spot on the equator, a flashing star marked the location of a synchronous satellite.

  From the star, two thin lines of light started to extend—one directly down toward the earth, the other in exactly the opposite direction, out into space.

  “When you build a bridge,” continued Morgan’s disembodied voice, “you start from the two ends and meet in the middle. With the Orbital Tower, it would be the exact opposite. You have to build upward and downward simultaneously from the synchronous satellite, according to a careful program. The trick is to keep the structure’s center of gravity always balanced at the stationary point. If you don’t, it will move into the wrong orbit, and start drifting slowly around the earth.”

  The descending line of light reached the equator; at the same moment, the outward extension also ceased.

  “The total height must be at least forty thousand kilometers, and the lowest hundred, going down through the atmosphere, may be the most critical part, because there the Tower may be subject to hurricanes. It won’t be stable until it’s securely anchored to the ground.

  “And then, for the first time in history, we will have a stairway to heaven—a bridge to the stars. A simple elevator system, driven by cheap electricity, will replace the noisy and expensive rocket, which will then be used only for its proper job of deep-space transport. Here’s one possible design for the Orbital Tower.”

  The image of the turning earth vanished as the camera swooped down toward the Tower, and passed through the walls to reveal the structure’s cross-section.

  “You’ll see that it consists of four identical tubes—two for up traffic, two for down. Think of it as a four-track vertical subway or railroad, from earth to synchronous orbit.

  “Capsules for passengers, freight, fuel would ride up and down the tubes, at several thousand kilometers an hour. Fusion power stations at intervals would provide all the energy needed; since ninety percent of it would be recovered, the net cost per passenger would be only a few dollars. As the capsules fall earthward again, their motors will act as magnetic brakes, generating electricity. Unlike re-entering spacecraft, they won’t waste all their energy heating up the atmosphere and making sonic booms; it will be pumped back into the system. You could say that the down trains will power the up ones. So even at the most conservative estimate, the Space Elevator will be a hundred times more efficient than any rocket.

  “And there’s virtually no limit to the traffic it could handle, for additional tubes could be added as required. If the time ever comes when a million people a day wish to visit Earth—or to leave it—the Orbital Tower could cope with them. After all, the subways of our great cities once did as much. . . .”

  Rajasinghe touched a button, silencing Morgan.

  “The rest is rather technical. He goes on to explain how the Tower can act as a cosmic sling, and send payloads whipping off to the moon and planets without the use of any rocket power at all. But I think you’ve seen enough to get the general idea.”

  “My mind is suitably boggled,” said Sarath. “But what on earth—or off it—has all this to do with me? Or with you, for that matter?”

  “Everything in due time, Paul. Any comments, Maxine?”

  “Pe
rhaps I may yet forgive you. This could be one of the stories of the decade—or the century. But why the hurry—not to mention the secrecy?”

  “There’s a lot going on that I don’t understand, which is where you can help me. I suspect that Morgan’s fighting a battle on several fronts; he’s planning an announcement in the very near future, but doesn’t want to act until he’s quite sure of his ground. He gave me that presentation on the understanding that it wouldn’t be sent over public circuits. That’s why I had to ask you here.”

  “Does he know about this meeting?”

  “Of course. He was actually quite happy when I said I wanted to talk to you, Maxine. Obviously, he trusts you and would like you as an ally. And as for you, Paul, I assured him that you could keep a secret for up to six days without apoplexy.”

  “Only if there’s a very good reason for it.”

  “I begin to see light,” said Duval. “Several things have been puzzling me, and now they’re starting to make sense. First of all, this is a space project; Morgan is Chief Engineer, Land.”

  “So?”

  “You should ask, Johan! Think of the bureaucratic infighting when the rocket designers and the aerospace industry get to hear about this! Trillion-dollar empires will be at stake, just to start with. If he’s not very careful, Morgan will be told ‘Thank you very much—now we’ll take over. Nice knowing you.’”

  “I can appreciate that, but he has a good case. After all, the Orbital Tower is a building—not a vehicle.”

  “Not when the lawyers get hold of it, it won’t be. There aren’t many buildings whose upper floors are moving at ten kilometers a second, or whatever it is, faster than the basement.”

  “You may have a point. Incidentally, when I showed signs of vertigo at the idea of a tower going a good part of the way to the moon, Morgan said, ‘Then don’t think of it as a tower going up; think of it as a bridge going out.’ I’m still trying, without much success.”

  “Oh!” said Duval suddenly. “That’s another piece of your jigsaw puzzle. The Bridge.”

  “What do you mean?”

  “Did you know that Terran Construction’s Chairman, that pompous ass Senator Collins, wanted to get the Gibraltar Bridge named after himself?”

  “I didn’t. That explains several things. But I rather like Collins. The few times we’ve met, I found him very pleasant, and very bright. Didn’t he do some first-rate geothermal engineering in his time?”

  “That was a thousand years ago. And you aren’t any threat to his reputation; he can be nice to you.”

  “How was the Bridge saved from its fate?”

  “There was a small palace revolution among Terran’s senior engineering staff. Morgan, of course, was in no way involved.”

  “So that’s why he’s keeping his cards close to his chest! I’m beginning to admire him more and more. But now he’s come up against an obstacle he doesn’t know how to handle. He discovered it only a few days ago, and it’s stopped him dead in his tracks.”

  “Let me go on guessing,” said Duval. “It’s good practice—helps me to keep ahead of the pack. I can see why he’s here. The earth end of the system has to be on the equator; otherwise it can’t be vertical. It would be like that tower they used to have in Pisa, before it fell over.”

  “I don’t see . . .” said Sarath, waving his arms vaguely up and down. “Oh, of course . . .” His voice trailed away into thoughtful silence.

  “Now,” continued Duval, “there are only a limited number of possible sites on the equator. It’s mostly ocean, isn’t it? And Taprobane’s obviously one of them. Though I don’t see what particular advantages it has over Africa or South America. Or is Morgan covering all his bets?”

  “As usual, my dear Maxine, your powers of deduction are phenomenal. You’re on the right line—but you won’t get any further. Though Morgan’s done his best to explain the problem to me, I don’t pretend to understand all the scientific details.

  “Anyway, it turns out that Africa and South America are not suitable for the Space Elevator. It’s something to do with unstable points in the earth’s gravitational field. Only Taprobane will do. Worse still, only one spot in Taprobane. And that, Paul, is where you come into the picture.”

  “Mamada?” yelped Sarath, indignantly reverting to Taprobani in his surprise.

  “Yes, you. To his great annoyance, Morgan has just discovered that the one site he must have is already occupied—to put it mildly. He wants my advice on dislodging your good friend Buddy.”

  Now it was Duval’s turn to be baffled.

  “Who?” she queried.

  Sarath answered at once. “The Venerable Anandatissa Bodhidharma Mahanayake Thero, incumbent of the Sri Kanda temple,” he intoned, almost as if chanting a litany. “So that’s what it’s all about.”

  There was silence for a moment. Then a look of pure mischievous delight appeared on the face of Paul Sarath, Emeritus Professor of Archaeology of the University of Taprobane.

  “I’ve always wanted,” he said dreamily, “to know exactly what would happen when an irresistible force meets an immovable object.”

  11

  The Silent

  Princess

  When his visitors had left, in a very thoughtful mood, Rajasinghe depolarized the library windows and sat for a long time staring out at the trees around the villa, and the rock walls of Yakkagala looming beyond. He had not moved when, precisely on the stroke of four, the arrival of his afternoon tea jolted him out of his reverie.

  “Rani,” he said, “ask Dravindra to get out my heavy shoes, if he can find them. I’m going up the Rock.”

  Rani pretended to drop the tray in astonishment.

  “Aiyo, Mahathaya!” she keened in mock distress. “You must be mad! Remember what Dr. McPherson told you.”

  “That Scots quack always reads my cardiogram backward. Anyway, my dear, what have I got to live for, when you and Dravindra leave me?”

  He spoke not entirely in jest, and was instantly ashamed of his self-pity. For Rani detected it, and the tears started in her eyes.

  She turned away so that he could not see her emotion, and said in English:

  “I did offer to stay—at least for Dravindra’s first year. . . .”

  “I know you did, and I wouldn’t dream of it. Unless Berkeley’s changed since I last saw it, he’ll need you there.” (Yet no more than I, though in different ways, he added silently to himself.) “And whether you take your own degree or not, you can’t start training too early to be a college president’s wife.”

  Rani smiled.

  “I’m not sure that’s a fate I’d welcome, from some of the horrid examples I’ve seen.” She switched back to Taprobani. “You aren’t really serious, are you?”

  “Quite serious. Not to the top, of course—only to the frescoes. It’s five years since I visited them. If I leave it much longer . . .” There was no need to complete the sentence.

  Rani studied him in silence for a few moments, and decided that argument was futile.

  “I’ll tell Dravindra,” she said. “And Jaya—in case they have to carry you back.”

  “Very well—though I’m sure Dravindra could manage that by himself.”

  Rani gave him a delighted smile, mingling pride and pleasure. This couple, he thought fondly, had been his luckiest draw in the state lottery, and he hoped that their two years of social service had been as enjoyable to them as it had been to him. In this age, personal servants were the rarest of luxuries, awarded only to men of outstanding merit. Rajasinghe knew of no other private citizen who had three.

  To conserve his strength, he rode a sun-powered tricycle through the pleasure gardens. Dravindra and Jaya preferred to walk, claiming that it was quicker. They were right; but they were able to take short cuts. He climbed very slowly, pausing several times for breath, until he had reached the long corridor of the Lower Gallery, where the Mirror Wall ran parallel to the face of the Rock.

  Watched by the usual inquisitive t
ourists, a young archaeologist from one of the African countries was searching the wall for inscriptions, with the aid of a powerful oblique light. Rajasinghe felt like warning her that the chance of making a new discovery was virtually zero. Paul Sarath had spent twenty years going over every square millimeter of the surface, and the three-volume Yakkagala Graffiti was a monumental work of scholarship that would never be superseded—if only because no other man would ever again be so skilled at reading archaic Taprobani inscriptions.

  They had both been young men when Paul had begun his life’s work. Rajasinghe could remember standing at this very spot while the then Deputy Assistant Epigrapher of the Department of Archaeology had traced out the almost indecipherable marks on the yellow plaster, and translated the poems addressed to the beauties on the rock above. After all these centuries, the lines could still strike echoes in the human heart:

  I am Tissa, Captain of the Guard.

  I came fifty leagues to see the doe-eyed ones,

  but they would not speak to me.

  Is this kind?

  May you remain here for a thousand years,

  like the hare which the King of the Gods

  painted on the moon. I am the priest Mahinda

  from the vihara of Tuparama.

  That hope had been partly fulfilled, partly denied. The ladies of the Rock had been standing here for twice the time that the cleric had imagined, and had survived into an age beyond his uttermost dreams. But how few of them were left! Some of the inscriptions referred to “five hundred golden-skinned maidens”; even allowing for considerable poetic license, it was clear that not one tenth of the original frescoes had escaped the ravages of time or the malevolence of men. But the twenty that remained were now safe forever, their beauty stored on countless films and tapes and crystals.

  Certainly they had outlasted one proud scribe, who had thought it quite unnecessary to give his name.

  I ordered the road to be cleared, so that pilgrims could

  see the fair maidens standing on the mountainside.