We were talking about ghosts. Mark had been even more vain, pompous and absurd than usual, and I could see that Miss Norris was irritated by it. After dinner she suggested dressing up as a ghost and frightening him. I thought it my duty to warn her that Mark took any joke against himself badly, but she was determined to do it. I gave way reluctantly. Reluctantly, also, I told her the secret of the passage. (There is an underground passage from the library to the bowling-green. You should exercise your ingenuity, Mr. Gillingham, in trying to discover it. Mark came upon it by accident a year ago. It was a godsend to him; he could drink there in greater secrecy. But he had to tell me about it. He wanted an audience, even for his vices.)