‘I can’t remember,’ said Noel, who had never seen one. Mattie had trusted her own judgement in all matters political, educational and medical, and Vee rigorously avoided talking to anyone at all in authority, just in case they wrongfooted her with a trick question such as ‘What is your name?’

‘I’ve noticed that you’ve recently had a growth spurt, which can accentuate minor ocular irregularities. But apart from that’ – the doctor peered at the cluster of organs laid out like a Lilliputian butcher’s display – ‘you’ve done quite well. Where is the spleen?’

‘I must have vented it,’ said Noel. There was no change of expression on the doctor’s face beyond a slight crease of puzzlement. ‘I don’t know,’ he amended, rather feebly.

‘Perhaps you should think about studying medicine,’ said Dr Parry-Jones as he helped her to clear up, swabbing the marble counter-top with disinfectant. ‘You have both the brain and the stomach for it.’ Noel mentally filed the suggestion next to ‘architectural historian’.

On the way back to Hampstead, the combination of Jeyes Fluid and formaldehyde meant that he had the front seat of the bus to himself. The morning frost had held hard, though a strip had melted along the very tops of the hedges, and the sight of this prompted Noel to ring the bell two stops early, and alight at Winnington Road. The official entrance to the nine-hole Hampstead golf course was halfway down it, but Noel took his usual route, walking brazenly along the side passage of a house called The Cedars, and squeezing between a fence post and a tree. He emerged into a crystalline world, every twig and bramble feathery with hoar frost, the grass of the fairway squeaking underfoot. A single golfer was visible in the far distance, teeing up on the third.

Noel kept to the sunlit parts of the course, his gaze on the ground. Almost immediately he spotted a ball at the edge of the rough, its skull-cap of ice newly melted. It was greenish-grey, old but intact, and he pocketed it and carried on looking, kneeling to grope around the familiar hollows at the base of a beech, and to prise the ice from a half-thawed rivulet. He’d found another two by the time he’d reached the solitary golfer.

‘Available for purchase,’ said Noel, holding out a ball.

‘Is it, indeed?’ The man looked at it speculatively. ‘How much?’

‘Six shillings.’

‘Oh, don’t be ridiculous.’

Noel nodded and turned away.

‘No, no, wait a moment.’

The man was already groping for his wallet. He was wearing a Russian fur hat, dewed with condensation, and a leather coat, a muffler at the neck. ‘Do you just have the one?’

‘Three, altogether.’

‘I’ll give you ten bob for them.’

‘No, the total for three is eighteen shillings.’

‘Don’t be cute. I’m bargaining.’

‘And I’m selling golf balls at six shillings apiece. You’re welcome to buy them elsewhere.’

‘Yes, very amusing, you know quite well that they’re not available.’ The man took off a glove and picked out two notes and a handful of coins. ‘I’ve been jewed, no doubt. Why aren’t you at school?’ he asked, stowing the balls in his golf bag.