I remember sitting in the dark and seeing the throat of the Khyber Pass at sunset - gloomy, ominous, mysterious, lonely, haunted by the ghosts of murdered men and by the prowling outlaws who live by the rifle and shun the daylight. As if the word were almost spoken in my ear I heard Death roosts in the Khyber while he preens his wings. It seemed like a good line, so I made a note of it.