Back in Scotland, our neighbours had been amazed at my father’s job offer. Freddie and Sylvie didn’t even bat an eye. I shrank back in my chair, embarrassed that I’d tried so obviously to impress them.

‘The “lunatic line”,’ Freddie said. ‘That’s what they call it around here.’

I’d heard the name too. My father didn’t like it.

‘Of course it was going to be a difficult project,’ he’d said once. ‘It was the biggest we’d ever undertaken.’ The line had taken five years to construct, and he’d lost many of his Indian workers, shipped over by the British for the job. They’d been struck down by dysentery or malaria, and, in the worst cases, the malaria developed into blackwater fever, where the red blood cells burst in the bloodstream.

‘You have to know the symptoms to look out for,’ he’d told us. ‘Chills, rigor, vomiting. Black urine was the worst. If we saw that, we knew they were as good as dead.’

Sylvie took a cigarette case out of the pocket of her slacks. Her fingers were slim and delicate, but her nails were ragged and unvarnished. ‘I took the train when I first got in,’ she said. There was a kind of bubble in her voice, like she was holding back laughter. ‘My husband was sick after eating that brown stuff they serve.’

‘Windsor soup,’ I said, surprised. I couldn’t imagine Freddie being ill.

She leaned forwards and lit her cigarette with our candle. ‘I hear it built the British Empire.’ She bowed her head when she was talking, making it hard to tell who she was looking at.

‘Oh, here’s William,’ my mother said.

We all turned to look at my father, who was picking his way around the other tables on the terrace. He knocked into the back of a white-haired old lady’s chair, and she glared at him. I wished suddenly that he was younger, more dashing.

‘I’m sorry I’m late, darling,’ he said to my mother as he reached us.

She tipped her face upwards to receive his kiss. ‘Freddie, Sylvie, this is my husband, William.’

My father held out his hand and Freddie removed his from my shoulder; Freddie’s nails were in much better condition than Sylvie’s – smooth and blush-coloured.

‘Pleased to meet you,’ my father said. He shook hands with Freddie and Sylvie then mopped his forehead with a handkerchief. Out of the corner of my eye I saw Freddie wipe his fingers on his trousers.

‘Would you like to join us for a drink?’ my mother asked.

‘We’d love to,’ Freddie said.

‘Theo, Maud, give up your seats,’ she said, and we hopped up.

The grown-ups ordered drinks and we hovered nearby, Maud busy cradling Roderigo. It was well after our usual suppertime, but I was still brimming with energy somehow, even with an empty stomach.