'That's the funny thing,' he explained.'1 don't really know, you see. I couldn't think of anything to write until just before Sampson got to me. Then those words just came into my head from nowhere and - it was very strange - I could see a sort of picture of it in my head. I think it means "Remember the well among the four trees". When Sampson read it he went quiet for a long time, then he started to ask me questions about my family and where 1 came from. Then he let me go.'