or won’t?’
Carey shrugged. ‘All right, then – won’t.’
‘Then I’m turning you down,’ said Denison.
Carey put down his pipe. ‘This is a question of state security, Denison; and we work on the principle of “need to know”. Mrs Hansen doesn’t need to know. Ian Armstrong doesn’t need to know. You don’t need to know.’
‘I’ve been kidnapped and stabbed,’ said Denison. ‘My face has been altered and my mind has been jiggered with.’ He raised his hand. ‘Oh, I know that – Harding got that much across – and I’m scared to the marrow about thinking of who I once was. Now you’re asking me to go on with this charade, to go to Finland and put myself in danger again.’ His voice was shaking. ‘And when I ask why you have the gall to tell me I don’t need to know.’
‘I’m sorry,’ said Carey.
‘I don’t care how sorry you are. You can book me on a flight to London.’
‘Now who is using blackmail?’ said Carey ironically.
‘It’s a reasonable request,’ said McCready.
‘I know it is, damn it!’ Carey looked at Denison with cold eyes. ‘If you breathe a word of what I’m going to tell you you’ll be behind bars for the rest of your life. I’ll see to that personally. Understand?’
Denison nodded. ‘I’ve still got to know,’ he said stubbornly.
Carey forced the words through reluctant lips. He said slowly, ‘It seems that in 1937 or 1938 Hannu Merikken discovered a way of reflecting X-rays.’
Denison looked at him blankly. ‘Is that all?’
‘That’s all,’ said Carey curtly. He stood up and stretched. ‘It isn’t enough,’ said Denison. ‘What’s so bloody important about that?’
‘You’ve been told what you want to know. Be satisfied.’
‘It isn’t enough. I must know the significance.’
Carey sighed. ‘All right, George; tell him.’
‘I felt like that at first,’ said McCready. ‘Like you, I didn’t see what all the fuss was about. Merikken was doing a bit of pure research when he came across this effect before the war and in those days there wasn’t much use for it. All the uses of X-rays depended upon their penetrative power and who’d want to reflect them. So Merikken filed it away as curious but useless and he didn’t publish a paper on it.’
He grinned. ‘The joke is that now every defence laboratory in the world is working out how to reflect X-rays, but no one has figured out a way to do it.’
‘What happened to make it important?’ asked Denison.
‘The laser happened,’ said Carey in a voice of iron.
‘Do you know how a laser works?’ When Denison shook his head, McCready said, ‘Let’s have a look at the very first laser as it was invented in 1960. It was a rod of synthetic ruby about four inches long and less than half an inch in diameter. One end was silvered to form a reflective surface, and the other end was half-silvered. Coiled around the rod was a spiral gas discharge lamp something like the flash used in photography. Got that?’
‘All clear so far.’
‘There’s a lot more power in these electronic flashes than people imagine,’ said McCready. ‘For instance, an ordinary flash, as used by a professional photographer, develops about 4,000 horse power in the brief fraction of a second when the condensers discharge. The flash used in the early lasers was more powerful than that – let’s call it 20,000 horse power. When the flash is used the light enters the ruby rod and something peculiar happens; the light goes up and down the rod, reflected from the silvered ends, and all the light photons are brought in step with each other. The boffins call that coherent light, unlike ordinary light where all the photons are out of step.
‘Now, because the photons are in step the light pressure builds up. If you can imagine a crowd of men trying to batter down a door, they’re more likely to succeed if they charge at once than if they try singly. The photons are all charging at once and they burst out of the half-silvered end of the rod as a pulse of light – and that light pulse has nearly all the 20,000 horse power of energy that was put into the rod.’
McCready grinned. ‘The boffins had great fun with that. They discovered that it was possible to drill a hole through a razor blade at a range of six feet. At one time it was suggested that the power of a laser should be measured in Gillettes.’
‘Stick to the point,’ said Carey irritably.
‘The military possibilities were easily seen,’ said McCready. ‘You could use a laser as a range-finder, for instance. Fire it at a target and measure the light bouncing back and you could tell the range to an inch. There were other uses – but there was one dispiriting fact. The laser used light and light can be stopped quite easily. It doesn’t take much cloud to stop a beam of light, no matter how powerful it is.’
‘But X-rays are different,’ said Denison thoughtfully.
‘Right! It’s theoretically possible to make an X-ray laser, but for one snag. X-rays penetrate and don’t reflect. No one has found a way of doing it except Merikken who did it before the war – and the working of a laser depends entirely upon multiple reflection.’
Denison rubbed his chin, feeling the flabbiness. Already he was becoming used to it. ‘What would be the use of a gadget like that?’
‘Take a missile coming in at umpteen thousand miles an hour and loaded with an atomic warhead. You’ve got to knock it down so you use another missile like the American Sprint. But you don’t shoot your missile directly at the enemy missile – you aim it at where the enemy will be when your missile gets up there. That takes time to work out and a hell of a lot of computing power. With an X-ray laser you aim directly at the enemy missile because it operates with the speed of light – 186,000 miles a second – and you’d drill a hole right through it.’
‘Balls,’ said Carey. ‘You’d cut the damned thing in two.’
‘My God!’ said Denison. That’s a death ray.’ He frowned. ‘Could it be made powerful enough?’
‘Lasers have come a long way since the first one,’ said McCready soberly. ‘They don’t use the flash any more on the big ones – they pour in the power with a rocket engine. Already they’re up to millions of horse power – but it’s still ordinary light. With X-rays you could knock a satellite out of orbit from the ground.’
‘Now do you understand the significance?’ asked Carey. When Denison nodded, he said, ‘So what are you going to do about it?’
There was a long silence while Denison thought. Carey stood up and went to the window where he looked across to the Studenterlunden, his fingers drumming on the window sill. McCready lay back on the bed with his hands behind his head, and inspected the ceiling closely.
Denison stirred and unclasped his fingers. He straightened in his chair and stretched his arms, then he sighed deeply. My name is Harry Meyrick,’ he said.
