(1) 24-48 hours after intra-muscular injection of the pure culture, inflammation of one or more of the heart valves commences. At this time, apart from a slight rise in temperature and occasional palpitations, no other symptoms are seen unless the horse is subjected to severe exertion, when auricular fibrillation or interference with the blood supply to the lungs occurs; both occasion severe distress which only resolves after 2-3 hours rest.

(2) Between the second and the sixth day pyrexia (tempera- ture rise) increases and white cell count of the blood increases and the horse is listless and off food. This could easily be loosely diagnosed as 'the virus'. However examination by stethoscope reveals a progressively increasing heart murmur. After about ten days the temp- erature returns to normal and, unless subjected to more than walk or trot, the horse may appear to have recovered. The murmur is still present and it then becomes necessary to retire the horse from fast work since this induces respiratory distress.

(3) Over the next few months vegetations grow on the heart valves, and arthritis in some joints, particularly of the limbs, may or may not appear. The condition is perma- nent and progressive and death may occur suddenly following exertion or during very hot weather, some- times years after the original infection.

I looked up. 'That's it, exactly, isn't it,' I said.

'Bang on the nose.'

I said slowly, 'Intra-muscular injection of the pure culture could absolutely not have occurred accidentally.'

'Absolutely not,' he agreed.

I said, 'George Caspar had his yard sewn up so tight this year with alarm bells and guards and dogs that no one could have got within screaming distance of Tri-Nitro with a syringeful of live germs.'

He smiled, 'You wouldn't need a syringeful. Come into the lab, and I'll show you.'

I followed him, and we fetched up beside one of the cupboards with sliding doors that lined the whole of the wall. He opened the cupboard and pulled out a box, which proved to contain a large number of smallish plastic envelopes.

He tore open one of the envelopes and tipped the contents onto his hand: a hypodermic needle attached to a plastic capsule only the size of a pea. The whole thing looked like a tiny dart with a small round balloon at one end, about as long, altogether, as one's little finger.

He picked up the capsule and squeezed it. 'Dip that into liquid, you draw up half a teaspoonful. You don't need that much pure culture to produce a disease.'

'You could hold that in your hand, out of sight,' I said.

He nodded. 'Just slap the horse with it. Done in a flash. I use these sometimes for horses that shy away from a syringe.' He showed me how, holding the capsule between thumb and index finger, so that the sharp end pointed down from his palm. 'Shove the needle in and squeeze,' he said.

'Could you spare one of these?' 'Sure,' he said, giving me an envelope. 'Anything you like.'

I put it in my pocket. Dear God in heaven.

Ken said slowly, 'You know, we might just be able to do something about Tri-Nitro.'

'How do you mean?' He pondered, looking at the large bottle of Zingaloo's blood, which stood on the draining board beside the sink.

'We might find an antibiotic which would cure the disease.'

'Isn't it too late?' I said.

'Too late for Zingaloo. But I don't think those vegetations would start growing at once. If Tri-Nitro was infected… say…'

'Say two weeks ago today, after his final working gallop.'

He looked at me with amusement. 'Say two weeks ago, then. His heart will be in trouble, but the vegetation won't have started. If he gets the right antibiotic soon, he might make a full recovery.'

'Do you mean… back to normal?'

'Don't see why not.'

'What are you waiting for?' I said.

CHAPTER FIFTEEN

I spent most of Sunday beside the sea, driving north-east from Newmarket to the wide deserted coast of Norfolk. Just for somewhere to go, something to do, to pass the time.

Even though the sun shone, the wind off the North Sea was keeping the beaches almost empty; small groups were huddled into the shelter of flimsy canvas screens, and a few intrepid children built castles.

I sat in the sun in a hollow in a sand dune which was covered with coarse tufts of grass, and watched the waves come and go. I walked along the shore, kicking the worm casts. I stood looking out to sea, holding up my left upper arm for support, aware of the weight of the machinery lower down, which was not so very heavy, but always there.

I had often felt released and restored by lonely places, but not on that day. The demons came with me. The cost of pride… the price of safety. If you didn't expect so much of yourself, Charles had said once, you'd give yourself an easier time. It hadn't really made sense. One was as one was. Or at least, one was as one was until someone came along and broke you all up.

If you sneezed on the Limekilns, they said in Newmarket, it was heard two miles away on the racecourse. The news of my attendance at Gleaner's post mortem would be given to George Caspar within a day. Trevor Deansgate would hear of it: he was sure to.

I could still go away, I thought. It wasn't too late. Travel. Wander by other seas, under other skies. I could go away and keep very quiet. I could still escape from the terror he induced in me. I could still… run away.

I left the coast and drove numbly to Cambridge. Stayed in the University Arms Hotel and, in the morning, went along to Tierson Pharmaceuticals Vaccine Laboratories. I asked for, and got, a Mr Livingston, who was maybe sixty and greyishly thin. He made small nibbling movements with his mouth when he spoke. He looks a dried-up old cuss, Ken Armadale had said, but he's got a mind like a monkey.

'Mr Halley, is it?' Livingston said, shaking hands in the entrance hall. 'Mr Armadale has been on the 'phone to me, explaining what you want. I think I can help you, yes I do indeed. Come along, come along, this way.'

He walked in small steps before me, looking back frequently to make sure I was following. It seemed to be a precaution born of losing people, because the place was a labyrinth of glass-walled passages with laboratories and gardens apparently intermixed at random.

'The place just grew,' he said, when I remarked on it. 'But here we are.' He led the way into a large laboratory which looked through glass walls into the passage on one side, and a garden on another, and straight into another lab on the third.

'This is the experimental section,' he said, his gesture embracing both rooms. 'Most of the laboratories just manufacture the vaccines commercially, but in here we potter about inventing new ones.'

'And resurrecting old ones?' I said. He looked at me sharply. 'Certainly not. I believe you came for information, not to accuse us of carelessness.'

'Sorry,' I said placatingly.

'That's quite right.'

'Well then. Ask your question.'

'Er, yes. How did the serum horses you were using in the nineteen forties get swine erysipelas?'

'Ah,' he said. 'Pertinent. Brief. To the point. We published a paper about it, didn't we? Before my time, of course. But I've heard about it. Yes. Well, it's possible. It's possible. It happened. But it shouldn't have done. Sheer carelessness, do you see? I hate carelessness. Hate it.'

Just as well, I thought. In his line of business, carelessness might be fatal.

'Do you know anything about the production of erysipelas antiserum?' he said.

'You could write it on a thumbnail.'

'Ah,' he said. 'Then I'll explain as to a child. Will that do?'

'Nicely,' I said.

He gave me another sharp glance in which there was this time amusement.

'You inject live erysipelas germs into a horse. Are you with me? I am talking about the past, now, when they did use horses. We haven't used horses since the early nineteen fifties, and nor have Burroughs Wellcome, and Bayer in Germany. The past, do you see?'