Heather flopped beside Cynthia with a grunt of relief. ‘I think I did stay in too long. Now I feel deliciously weak in the legs.’

‘You’re certainly a glutton,’ Cynthia said, ‘for physical exercise.’

‘Yes, isn’t it hideous? I was just like that at school. In theory the only thing I wanted to be was one of those pale, interesting girls, riddled with elegance and constipation. But I found myself captain of the netball team, captain of the lacrosse team, captain of tennis, and opening bat in the cricket team. I just couldn’t resist running and jumping and making an ass of myself.’

‘All very healthy.’

‘Horribly,’ Heather agreed. ‘But I thought I’d got over it. I really must put my foot down with myself for the rest of our time here.’

‘Why?’

‘I daren’t go back home complaining of physical fatigue. I’ve got two younger brothers, with the filthiest kind of late adolescent minds, and no scruples about expressing them.’