“A very great deal, Mister Ambassador,” answered the engineer, suddenly equally serious and formal. “You are quite correct in thinking that this material will have many applications, some of which we are only now beginning to foresee. And one of them, for better or for worse, is going to make your quiet little island the centre of the world. No – not merely the world. The whole Solar System. Thanks to this filament, Taprobane will be the steppingstone to all the planets. And one day, perhaps – the stars.”

Paul and Maxine were two of his best and oldest friends, yet until this moment they had never met nor, as far as Rajasinghe knew, even communicated. There was little reason why they should; no-one outside Taprobane had ever heard of Professor Sarath, but the whole Solar System would instantly recognise Maxine Duval, either by sight or by sound.

His two guests were reclining in the library's comfortable lounge chairs, while Rajasinghe sat at the villa's main console. They were all staring at the fourth figure, who was standing motionless.

Too motionless. A visitor from the past, knowing nothing of the everyday electronic miracles of this age, might have decided after a few seconds that he was looking at a superbly detailed wax dummy. However, more careful examination would have revealed two disconcerting facts. The “dummy” was transparent enough for highlights to be clearly visible through it; and its feet blurred out of focus a few centimetres above the carpet.

“Do you recognise this man?” Rajasinghe asked.

“I've never seen him in my life,” Sarath replied instantly. “He'd better be important, for you to have dragged me back from Maharamba. We were just about to open the Relic Chamber.”

“I had to leave my trimaran at the beginning of the Lake Saladin races,” said Maxine Duval, her famous contralto voice containing just enough annoyance to put anyone less thick-skinned than Professor Sarath neatly in his place. “And I know him, of course. Does he want to build a bridge from Taprobane to Hindustan?”

Rajasinghe laughed. “No – we've had a perfectly serviceable causeway for two centuries. And I'm sorry to have dragged you both here – though you, Maxine, have been promising to come for twenty years.”

“True,” she sighed. “But I have to spend so much time in my studio that I sometimes forget there's a real world out there, occupied by about five thousand dear friends and fifty million intimate acquaintances.”

“In which category would you put Dr. Morgan?”

“I've met him – oh, three or four times. We did a special interview when the Bridge was completed. He's a very impressive character.”

Coming from Maxine Duval, thought Rajasinghe, that was tribute indeed. For more than thirty years she had been perhaps the most respected member of her exacting profession, and had won every honour that it could offer. The Pulitzer Prize, the Global Times Trophy, the David Frost Award – these were merely the tip of the iceberg. And she had only recently returned to active work after two years as Walter Cronkite Professor of Electronic Journalism at Columbia.

All this had mellowed her, though it had not slowed her down. She was no longer the sometimes fiery chauvinist who had once remarked: “Since women are better at producing babies, presumably Nature has given men some talent to compensate. But for the moment I can't think of it.” However, she had only recently embarrassed a hapless panel chairman with the loud aside: “I'm a newswoman, dammit – not a newsperson.”

Of her femininity there had never been any doubt; she had been married four times, and her choice of REMS was famous. Whatever their sex, Remotes were always young and athletic, so that they could move swiftly despite the encumbrance of up to twenty kilos of communications gear. Maxine Duval's were invariably very male and very handsome; it was an old joke in the trade that all her REMs were also RAMS. The jest was completely without rancour, for even her fiercest professional rivals liked Maxine almost as much as they envied her.

“Sorry about the race,” said Rajasinghe, “but I note that Marlin III won very handily without you. I think you'll admit that this is rather more important… But let Morgan speak for himself.”

He released the PAUSE button on the projector, and the frozen statue came instantly to life.

“My name is Vannevar Morgan. I am Chief Engineer of Terran Construction's Land Division. My last project was the Gibraltar Bridge. Now I want to talk about something incomparably more ambitious.”

Rajasinghe glanced round the room. Morgan had hooked them, just as he had expected.

He leaned back in his chair, and waited for the now familiar, yet still almost unbelievable, prospectus to unfold. Odd, he told himself, how quickly one accepted the conventions of the display, and ignored quite large errors of the Tilt and Level controls. Even the fact that Morgan “moved” while staying in the same place, and the totally false perspective of exterior scenes, failed to destroy the sense of reality.

"The Space Age is almost two hundred years old. For more than half that time, our civilisation has been utterly dependent upon the host of satellites that now orbit Earth. Global communications, weather forecasting and control, land and ocean resources banks, postal and information services – if anything happened to their space-borne 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 indeed 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 generations of research have 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 ultra-violet break-through – 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 anti-gravity or of 'spacedrives'. No-one has ever found the slightest hint that such things are possible; today we believe that they are only fantasy. And yet, in the very decade that the first satellite was launched, 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 which, nowadays, seldom impinged upon his life.