‘I got it in writing,’ shouted Smith belligerently. ‘I’m not childish yet. I got it in writing while he was still worried I’d turn nasty over the train. Far-sighted. That’s me.’

Dikon burst out laughing.

‘Aw, turn it up and go to hell,’ roared Smith. ‘I’m a disappointed man. I’m going to bed.’ He gave an indignant belch and left them.

‘He’d be all right,’ said Simon apologetically, ‘if he kept off the booze.’

‘Have you told him about your views on Questing?’

‘Not more than I could help. You can’t be sure he won’t talk when he’s got one or two in. He still reckons Questing went up to the Peak for curios. I didn’t say anything. You want to keep quiet about the signals.’

‘Yes,’ agreed Dikon and rubbed his nose. ‘On that score I’m afraid you’re not going to be very pleased with me.’ And he explained that he had told the whole story to the Colonel and Dr Ackrington. Simon took this surprisingly well, reserving his indignation for Mr Falls’s behaviour at Taupo-tapu which Dikon now revealed to him. In Simon’s opinion Falls had no right, however suspicious the circumstances, to exceed the limit that he himself had set. ‘I don’t like that joker,’ he said. ‘He’s a darned sight too plausible.’

‘He’s no fool.’

‘I reckon he’s a crook. You can’t get away from those signals.’

Rather apprehensively Dikon advanced Dr Ackrington’s views on the signals. ‘And I must confess,’ he added, ‘that to me it seems a likely explanation. After all, why on earth should Falls take such an elaborate and senseless means of introducing himself to Questing? All he had to do was to take Questing on one side and present his credentials. Why run the danger of someone spotting the signal? It doesn’t make sense.’

Unable to answer this objection, Simon angrily reiterated his own views. ‘And if you think I’m dopey,’ he stormed, ‘there are others that don’t. You may be interested to hear I went to the police station this afternoon.’ He observed Dikon’s astonishment with an air of satisfaction. ‘Yes,’ he said, ‘after you’d told me it was Falls tapped out the signal, I hopped on my bike and got going. I know the old sergeant and I got on to him. He started off by acting as if I was a kid but I convinced him. Well, anyway,’ Simon amended, ‘I stuck to it until he let me in to see the super.’

‘Well done,’ Dikon murmured.