‘Oh, yes, I heard about her.’

‘That’s when they had their big falling-out, Jacques and Thomas. Anyway, she had a room over the cloister, number twenty-three it was. This was before they were married, when she’d come as a patient. She had lovely skin, very soft, I can still remember. She was always friendly when I went in, then she’d take off her dressing gown and lie there in silence. She was quite strong, you could feel the muscles, even though she was slim. She had ever such sharp little knees, I remember. But there was so much tension as well – and I had to use my elbow sometimes between her shoulders and it made her cry out. But she used to be asleep at the end and I’d cover her with an eiderdown. Anyway, she told Thomas I was a miracle worker and that changed his mind. Though what made her better really was having an operation in the hospital.’

‘And was the clinic a happy place back then or was it … strange?’

‘Sonia and Kitty were the best thing. They were the sun in the morning, we used to say. Jacques was a very clever man and he wanted to help, but he could be moody. Thomas was more cheerful, you never heard him say an unkind word, but he worked too hard. When he’d finished for the day, he’d go underground into that laboratory and work some more.’

Lena looked over at the building, the whitewashed walls and tile roofs behind the birches and the chestnut tree. It looked too placid to contain that much passion, the mania and the arguments. She’d throw away the charcoal sketches and try to use paint: oils might be able to suggest the sun in the morning as well as the shadows at night.

‘Mary, can I draw you now?’

‘You can if you like,’ said Mary.

‘Just sit like that. Don’t move.’

After a few minutes’ silent work, using principles from her evening classes, Lena said, ‘What’s Charlotte like? The other twin? Is she nice?’

‘Oh yes. I think she found it difficult making a life for herself away from the clinic. The clinic was family, a school, a whole world for those little girls. They were adored by all the patients and the staff. But they went back to London for a time, the family. The girls went to a college, then Martha was a schoolmistress for a bit and I think Charlotte worked in an office. And then Thomas fell ill with dementia. The Schloss didn’t do so well after that, but Jacques was doing his own work in Paris and was finished with us. So it was decided that one of the girls should come back and one of them should help look after Thomas. And they always say they just tossed a coin to see which one would come.’

‘It’s funny neither of them’s married.’

‘I know. And them nice-looking as well.’

‘How can you tell?’