‘You did!’ exclaimed Gerald. ‘That’s one of the things I’ve never ever seen done. You mean jiu-jitsu, I suppose?’

‘Yes. But I am no good at those things — they don’t interest me.’

‘They don’t? They do me. What’s the start?’

‘I’ll show you what I can, if you like,’ said Birkin.

‘You will?’ A queer, smiling look tightened Gerald’s face for a moment, as he said, ‘Well, I’d like it very much.’

‘Then we’ll try jiu-jitsu. Only you can’t do much in a starched shirt.’

‘Then let us strip, and do it properly. Hold a minute —