‘Have you had enough, Roddy?’

‘Soon.’

‘Do you prefer watching?’

‘I always prefer watching.’

It was true. He would watch with deep concentration while others moved and took exercise, as if he were drawing them in his mind or getting them by heart; but his own impulses towards physical activity were rare and of brief duration.

‘I like swimming,’ said Judith; careful not to say she adored it.

‘You do it very nicely.’

‘But this is dull compared with swimming at night.’

‘Ah!

‘Have you ever done that?’