The Fountains of Paradise

"Capsules for passengers, freight, fuel would ride up and down the tubes at several thousand kilometres an hour. Fusion power stations at intervals would provide all the energy needed; as ninety percent of it would be recovered, the net cost per passenger would be only a few dollars. For as the capsules fall earthwards 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 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 in mid-sentence.

"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 Professor 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?"

"Perhaps 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; indeed, he was 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 Maxine 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?"

"Yhu should ask, Johan! Think of the bureaucratic in-fighting, 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 very 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 kilometres 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, Dr. 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 Maxine Duval suddenly. "That's another piece of your jig-saw 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 him?"

"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. Dr. 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 only discovered it a few days ago, and it's stopped him dead in his tracks."

"Let me go on guessing," said Maxine. "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 Professor Sarath, waving his arms vaguely up and down. "Oh, of course…" His voice trailed away into a thoughtful silence.