Two children who've grown up, who once thought they were sisters and later realized that they were only neighbors, and who were separated rather quickly by the elevated train built over the street separating their houses. Everyday, people went by overhead, and they could barely hear each other when they were able to get together to play because the squeaky tracks were used to full capacity by heavy trains that went by almost every other sentence. So, when ghosts gather overhead and chat, here in later years in the mourning room of the Tavistock Square medium, they have long ago learned to keep their quiet, as the voices roar by overhead.     Each Sunday, ghosts would appear at a seance in Tavistock Square, to be photographed with the living by Ella and her special camera.