Chapter Five

      The word research, from the lips of Roberta Ryder, held certain negative past associations for Ben. After all, it had been some bizarre experimental research of her own that had first not only brought them together but drawn the attention of ruthless people who’d very nearly succeeded in killing them both.

      ‘You told me Claudine was a lecturer,’ he said. ‘Lecturer in what?’

      ‘Physics,’ Roberta replied.

      ‘It doesn’t sound very dangerous.’

      ‘But then, what do you know about physics?’

      He said nothing. Aside from weapons ballistics, the complexities of calculating long-range rifle bullet trajectories, the cold mathematics of war and destruction that he wanted to forget he’d ever learned, he didn’t know much.

      ‘That’s what I thought,’ she said. ‘Then I don’t suppose you’ve ever heard of a guy called Tesla? He was the subject of Claudine’s research, ever since I first knew her.’

      ‘Of course I’ve heard of him,’ he said defensively. ‘First to experiment with electricity, back in the nineteenth century. Made dead frogs’ legs dance about by passing current through them. I don’t see what—’

      ‘That was Galvani, Ben,’ Roberta interrupted impatiently. ‘I’m talking about the great Serbian scientist Nikola Tesla, born 1856. Actually I’m not surprised you didn’t know about him,’ she added after a beat. ‘I mean, everyone’s heard of the Marconis and Faradays and Edisons of this world, but Tesla’s the pioneer genius who somehow wound up forgotten. Which is pretty incredible, considering he came up with the principles behind wireless communication, remote control, radar, sonar, robotics, neon and fluorescent light, and foresaw the internet and cell phones as early as 1908. Not to mention his work on—’

      ‘I get the picture,’ Ben interrupted, knowing she was liable to launch into a whole science lecture if he didn’t break her stream.

      ‘I don’t know that you do get it,’ she said. She paused a moment. Gazed across the park, where the young mother was still pushing her son to and fro on the swing. The child was howling in delight as the swing’s arc carried him higher and higher.

      ‘Look at that,’ Roberta said, pointing. ‘That kid’s mother can’t weigh more than a hundred and five pounds soaking wet. She’s even smaller than I am. But see how little force it takes, at just the right moment, to make the swing go up high in the air.’ She looked round at Ben. ‘That’s what Claudine’s research was about.’

      ‘About shoving a kid back and forth on a swing?’

      She tutted. ‘Don’t be so obtuse, Hope. It’s about the principle of resonance, the idea that tiny forces, precisely enough timed and placed, can accumulate to create massive energies.’

      ‘You’re going to have to be more specific.’

      ‘Okay, let me put it another way. The Earth’s vibrations have a periodicity of about an hour forty-nine minutes. In other words, if I were to hit something solid against the ground right now, it would send a wave of contraction through the whole planet that would return to the same point one hour forty-nine minutes later in the form of expansion. Follow me?’

      ‘Oh, absolutely,’ he said.

      Missing his sarcasm, she went on: ‘So you see, the Earth, like everything else, is in a constant state of vibration, ever expanding and contracting. Now imagine that at the exact moment when it begins to contract, I detonate a ton of high explosive in the exact same spot. That would accelerate the contraction, so that one hour forty-nine minutes later there would come back a wave of expansion that was equally accelerated. Now, if as that expansion wave began to ebb I set off another ton of explosive, and I kept repeating that pattern again and again … eventually, what do you suppose would happen?’

      Ben looked blank.

      ‘It’s obvious, if you think about it. Given time, Tesla calculated that he could build up enough of an energy wave to split the Earth.’

      ‘Split the Earth,’ Ben repeated in a flat tone.

      She nodded matter-of-factly, as if splitting the Earth were all part and parcel of a scientist’s everyday routine. ‘That’s the idea. See? Small input, big effect. Pretty much all of Tesla’s work was based on those principles, and that’s what Claudine was interested in. She was talking about it when I first met her, and she was still talking about it the last time we had a conversation on the phone, which was about five months ago.’

      ‘I still don’t understand where this is leading, Roberta.’

      ‘Let me explain a little more, okay? In the late nineteenth century Tesla invented a small hand-held device called the electro-mechanical oscillator. Based on the same kind of principles, he used it to show that even a subtle vibration, at just the right frequency, could unleash a whole lot of power. I mean enormous, and almost instantaneously. Enough to, say, bring down a building. A house, even a skyscraper.’

      ‘Sounds more like a bomb to me.’

      ‘No explosives involved,’ she replied, shaking her head. ‘No noise or smoke, nothing chemical, just some basic mechanical moving parts powered by steam.’

      ‘Steam? What kind of bollocks contraption is that?’

      ‘A very simple one. Basically a miniature piston engine, with a small on-board boiler heated by internal combustion. In those days, steam was the only power source that could produce enough energy to operate the mechanicals. The whole thing was supposed to have been about six, seven inches long. You could carry it in your pocket.’

      ‘And use it to bring down a building.’

      She nodded. ‘Sure.’

      ‘But it can’t split the Earth.’

      ‘Oh no, you’d need a bigger version to do that kind of damage.’

      ‘I would have hoped you’d do me more credit than to expect me to believe such utter bloody nonsense,’ he said. ‘I mean, come on.’

      ‘It really existed, Ben,’ Roberta insisted. ‘According to Tesla’s findings its theoretical potential was limitless.’

      Ben was losing patience. ‘Theoretical, as in, it’s never actually been done or proved. This is what your friend was into? And you think this is why someone killed her? To do with some pie-in-the-sky notion that you can vibrate a building to pieces with some daft Heath Robinson device?’ He waved his hand dismissively. ‘Listen, I spent years in the army learning how to blow stuff up. Nobody can do it as efficiently as we did. Millions are spent developing high-tech explosives and training people like me how to use them without getting themselves