They had by this time reached the marks.
‘Here we are,’ said Burnley. ‘What do you think of these?’
‘I don’t see anything very remarkable about them.’
‘Look again.’
Felix shook his head.
‘See here, Mr. Felix. Stand out here on the gravel and put your right foot in line with this first print. Right. Now take a step forward as if you were walking to the house. Right. Does anything occur to you now?’
‘I can’t say that it does, unless it is that I have taken a very much longer step.’
‘But your step was of normal length.’
‘Well then, conversely, the unknown must have taken a short one.’
‘But did he? Assume it was Watty, as I think it must have been. You were with him and you saw him walking.’