'Sorry, old chap,' he said simply. 'I thought you understood.'

Ken smiled back.

'I'm afraid I took it for granted that you had it all pat. You see, I don't know the first thing about mountaineering myself. Can't we get back the same way we came?'

Roy shook his head.

'It's too big a reach. But don't worry. We'll find some way out. Stop here a minute and I'll go and have a squint round.'

Ken looked at him.

'You'll be careful, Roy? Hadn't I better come and give you a hand?'

'I'll call you if I want you,' said Roy. 'I'm going to see where this ledge leads.'

He strolled off as calmly as though walking along a twelve-inch ledge over a two hundred foot drop was as simple as a promenade down the sunny side of Piccadilly. Ken, feeling anything but happy, watched him until he was hidden behind a shoulder of rock.

It was quite five minutes before he came back.