‘Good for him,’ said Charmian.

Windsor Castle was just over the other side of the Thames, and ever since Henry VI’s day, the English monarchs had taken varying degrees of interest in the school. A boy had once saved the life of Queen Victoria when a madman had tried to shoot her outside the railway station. James had seen the current king, George V, on a couple of occasions, and often wondered what the life of a king must be like, behind those high castle walls.

Charmian took James for lunch at a restaurant on the river and afterwards they made their way down to some meadows next to the river known as the Brocas. A large and excited crowd had gathered here, ready for the main highlight of the day, the Procession of Boats.

The sun was sparkling on the water, turning the usually dull and muddy Thames an attractive bright blue speckled with silver shards.

‘How are you getting on with your lessons?’ Charmian asked, turning her face to catch the sun.

‘I don’t suppose I’ll win many prizes for my work,’ James said. ‘I try to be interested in it all, but I do sometimes wonder what the point of studying Latin is.’

Charmian laughed. ‘Well, don’t ask me! They didn’t teach me much more at school than how to snag a husband. And I don’t think I can have paid enough attention in those particular lessons. Now, good Lord, what’s this?’

The first of the boats had appeared from under the railway bridge, being rowed by a crew of boys wearing old-fashioned sailors’ outfits from Nelson’s time – white trousers, striped shirts, blue jackets and straw hats decorated with huge bunches of flowers. A tiny cox sat in the back, dressed as a miniature admiral, steering.

As the boats reached the end of the Brocas, the rowers stood up and held their oars upright beside them in the boats, a tricky and wobbly manoeuvre. James, like many of the boys watching, hoped that someone might fall in, but it didn’t happen today.

As the other boats went past Charmian turned to James.

‘I know what I’ve been meaning to talk to you about,’ she said. ‘The holidays.’

‘Are you still going away?’ said James.

‘I’m afraid so. It’s the chance of a lifetime. An expedition up the Amazon. We’ll be meeting tribes who’ve never seen an outsider. With a way of life unchanged for thousands of years…’ She paused for a moment and put an arm round James. ‘I’m sorry to abandon you,’ she said, ‘but perhaps we can think of a tame relative to pack you off to.’

‘I’ll be all right,’ said James.

‘I’m sure you will,’ said Charmian.

James stepped back to get a better view and, in so doing, trod on someone’s foot. He turned round to apologise.

It was Mr Merriot, James’s classical tutor.

‘Steady on, there, James,’ he said, with a smile. Merriot was tall, with unruly grey hair and long, gangly arms and legs, like a stick insect. As usual, an unlit pipe jutted out of his face from beneath his big beaky nose.