Francis turned the repair around faster than expected. Less than a week later, I returned to collect my machine and the bill cured me of any sentimentality. Francis charged me £90 for the repair and £10 each for two new ribbons. This time, I took a closer look at the price tags of the typewriters on the shelves and I understood that nostalgia was not his motive for continuing in his occupation. As one of only a handful of people in the country still selling and servicing manual typewriters, he was able to charge what he liked. The twenty-first century, confounding all expectations, was a good moment to be in the manual typewriter business.

‘Castle, wasn’t it?’ he said, as he passed me my handwritten receipt. It took me a second to understand.

He led me to the back of the shop and worked himself slowly down the stairs into the basement. The room was lit by a series of naked bulbs that he frugally switched on and off as we made our way along a narrow corridor between wooden shelves piled with old machines. They weren’t just typewriters: there were old fax machines and printers, as well as various primordial computers. I had the impression that the basement had been extended out far under the main road, and I wondered if it was entirely legal.

Finally, in a puddle of yellow light from a bulb above it, stood a shabby pine roll-top desk. ‘Castle,’ he said, and jabbed a brown thumb at the picture that lay on the desktop.

It was a team photograph of men and boys in woollen bathing suits. They were standing in formation in front of the building that once served as the main entrance to the lido. Beneath it was written ‘Streatham and Surrey Swimming Club, 1914’. Francis turned it over. A piece of yellowing paper was glued to its reverse side, with a list of names typed on it. Between ‘G. L. K Townsend’ and ‘A. P. Quinlon’ I read ‘W. L. Castle’. The man it referred to looked uncannily like my son – something about his pointed chin, and the way his eyes crinkled against the light.

Was it Leonard? It struck me that someone might easily have transposed the letters of his first and second names. I wasn’t sure of Leonard’s middle name, but my grandfather’s was Wallace, and that seemed like a form of confirmation.

I asked Francis if I could borrow the photograph and show it to my mum. A careful, shrewd look came into his face. He said it was too precious to let it out of his sight, but he’d see if he could make a copy.

*

YOU’D THINK WRITERS would be story-proof, would understand how all narrative attempts to understand the world are partial and misleading. Not a bit of it. The writer is usually the most wedded to a story, the most deceived, his own first dupe.