'What do they say?' I asked. 'What sort of things?'

'Only what you'd expect. The weather, the journey, the scenery. They ask what time we get to Sudbury, eh? Or Thunder Bay, or Winnipeg, or whatever.'

'Has anyone asked anything that was different, or surprised you?'

'Nothing surprises me, sonny.' He glowed with irony and bonhomie. 'What would you expect them to ask?

I shrugged in frustration. 'What happened before Thunder Bay that shouldn't have?''The Lorrimores' car, eh?'

'Apart from that.'

'You think something happened?'

'Something happened, and I don't know what, and it's what I'm here to prevent.'

He thought about it, then said, 'When it turns up, you'll know, eh?'

'Maybe.'

'Like if someone put something in the food, eh?, sooner or later everyone will be ill.'

'George!' I was dumbstruck.

He chuckled. 'We had a waiter once years ago who did that. He had a grudge against the world. He put handfuls of ground-up laxative pills into the chocolate topping over ice cream and watched the passengers eat it, and they all had diarrhoea. Dreadful stomach pains. One woman had to go to hospital. She'd had two helpings. What a to-do, eh?'

'You've frightened me stiff,' I said frankly. 'Where do they keep the fodder for the horses?'

He stared, his perpetual smile fading.

'Is that what you're afraid of? Something happening to the horses?'

'It's a possibility.'

'All the fodder is in the horse car,' he said, 'except for some extra sacks of those cubes most of the horses are having, which are in the baggage car. Some of the horses have their own special food brought along with them, sent by their trainers. One of the grooms had a whole set of separate bags labelled, "Sunday evening", "Monday morning" and so on. He was showing them to me.'

'Which horse was that for?'

'Um… the one that belongs to that Mrs Daffodil Quentin, I think. The groom said one of her horses died of colic or some such recently, from eating the wrong things, and the trainer didn't want any more accidents, so he'd made up the feeds himself.'

'You're brilliant, George.'

His ready laugh came back.

'Don't forget the water tank, eh? You can lift the lid… where the plank floats, remember? You could dope all those horses at once with one quick cupful of mischief, couldn't you? '

Leslie Brown told us adamantly that no one could possibly have tampered with either the fodder or the water.

'When did the grooms last fill the buckets?' I asked.

During the morning, she said. Each groom filled the bucket for his own horse, when he wanted to. All of them had been in there, seeing to their charges.

The horses' drinking-water tank had been topped up, she said, by a hosepipe from the city's water supply during the first twenty minutes of our stop in Thunder Bay, in a procedure that she herself had supervised.

George nodded and said the whole train had been re-watered at that point.

'Before Thunder Bay,' I said, 'could anyone have put anything in the water?'

'Certainly not. I've told you over and over again, I am here all the time.'

'And how would you rate all the grooms for trustworthiness?' I said.

She opened her mouth and closed it again and gave me a hard look.

'I am here to supervise them,' she said. 'I didn't know any of them before yesterday. I don't know if any of them could be bribed to poison the water. Is that what you want?'

'It's realistic,' I said with a smile.

She was unsoftened, unsoftenable

'My chair, as you see,' she said carefully, 'is next to the water tank. I sit there and watch. I do not think… I repeat, I do not believe, that anyone has tampered with the water.'

'Mm,' I said calmingly. 'But you could ask the grooms, couldn't you, if they've seen anything wrong.'

She began to shake her head automatically, but then stopped and shrugged. 'I'll ask them, but they won't have.'

'And just in case,' I said, 'in case the worst happens and the horses prove to have been interfered with, I think I'll take a sample of what's in the tank and also what's in their buckets at this moment You wouldn't object to that, Ms Brown, would you?'

She grudgingly said she wouldn't. George elected himself to go and see what could be done in the way of sample jars and presently returned with gifts from the Chinese cook in the dome car, in the shape of four rinsed-out plastic tomato-sauce bottles rescued from the rubbish bin.

George and Leslie Brown took a sample from the tank, draining it, at the dragon's good suggestion, from the tap lower down, where the buckets were filled. I visited Voting Right, Laurentide Ice and Upper Gumtree, who all graciously allowed me to dip into their drink With Leslie Brown's pen, we wrote the provenance of each sample on the sauce label and put all four containers into a plastic carrier bag which Leslie Brown happened to have handy.

Carrying the booty, I thanked her for her kindness in answering our questions, and helping, and George and I retreated.

'What do you think?' he said, as we started back through the train.

'I think she now isn't as sure as she says she is.'

He chuckled 'She'll be doubly careful from now on.'

'As long as it's not already too late '

He looked as if it were a huge joke 'We could get the tank emptied, scrubbed and refilled at Winnipeg,' he said.

'Too late If there's anything in it, it was there before Thunder Bay, and the horses will have drunk some of it.

Some horses drink a lot of water… but they're a bit fussy. They won't touch it if they don't like the smell If there's traces of soap in it, for instance, or oil. They'd only drink doped water if it smelled all right to them

'You know a lot about it,' George commented

'I've spent most of my life near horses, one way and another '

We reached his office where he said he had some paperwork to complete before we stopped fairly soon for ten minutes at Kenora. We would be there at five-twenty, he said. We were running thirty minutes behind the Canadian. There were places the race train didn't really need to stop, he said, except to keep pace with the Canadian. We needed always to stop where the trains were serviced for water, trash and fuel.

I had nowhere on our journey to and from the horse car seen the man with the gaunt face George had pointed someone out to me in the dayniter, but he was not the right person grey haired, but too ill-looking, too old The man I was looking for, I thought, was fifty-something, maybe less, still powerful; not in decline.

In a vague way, I thought, he had reminded me of Derry Welfram. Less bulky than the dead frightener, and not as smooth, but the same stamp of man. The sort Filmer seemed to seek out naturally.

I sat for an hour in my roomette looking out at the unvarying scenery and trying to imagine anything else that Filmer might have paid to have done. It was all the wrong way round, I thought' it was more usual to know the crime and seek the criminal, than to know the criminal and seek his crime.

The four sample bottles of water stood in their plastic carrier on my roomette floor. To have introduced something noxious into that tank, gaunt-face would certainly have to have bribed a groom. He wasn't one of the grooms himself, though perhaps he had been one, somewhere, some time. The grooms on the train were all younger, thinner and from what I'd seen of them in their uniform T-shirts less positive. I couldn't imagine any of them having the nerve to stand up to Filmer and demand their money.

I spent the brief stop at the small town of Kenora hanging out of the open doorway past George's office, watching him, on the station side of the train, walk a good way up and down outside while he checked that all looked well. The Lorrimores' car, it appeared, was still firmly tacked on. Up behind the engine, two baggage handlers were loading a small pile of boxes. I hung out of the door on the other side of the train for a while, but no one was moving out there at all.