One curious incident in the story is the instantaneous appearance on the stairs of the woman herself and her ghostly double, one in a white dress, one in the fatal blue. This sort of spectral warning, this wireless service for the conveyance of bad news and hint of threatening danger, serves to link the ghost story of the present with those of the past. The records of the Psychical Society show hundreds of such instances, and much use is made in fiction of plots hinging on such motif. Scott's White Lady of Avenel appears as a death portent, as also the "Bahr-geist" in another novel. [127] In _The Substitute_. [128] In _A Haunted Island_. The revenge ghost looms large in fiction as in the drama. He was the most important figure in Elizabethan as in classical drama, and Shakespeare's ghosts are principally of that class. A terrible example of the type is in Robert Lovell Beddoes' _Death's Jest-Book_, that extraordinary example of dramatic supernaturalism, where the ghost of the murdered man comes back embodied from the grave and is an active character to the end of the play. He is summoned to life through a hideous mistake, the murderer having asked the magician to call up the spirit of his dead wife, but the body of his victim having been secretly buried beside her so that the murderer may have no rest even in the grave, the awful accusing spirit rises to confront him, instead of his wife's phantom. The revenge ghost is both objective and subjective in his manifestation and his impelling motive adds a touch of frozen horror to his appearance. He appears in various forms, as dismembered parts of the body--illustrated in the stories above referred to,--in a horrific invisibility, in a shape of fear visible only to the guilty, or in a body so objectified as to seem absolutely real and living to others beside the one haunted. The apparently casual, idle figure that strolls about the docks and streets in _The Detective_, seen by different persons and taken for a man interested only in his own pursuits, is a revenge ghost so relentless that he hounds his victim from country to country, at last killing him by sheer force of terror as he sits on his bed at night, leaving the imprint of his body on the mattress beside the dead man whose face is rigid with mad horror. He has come back in physical embodiment to avenge the betrayal of his daughter. Ambrose Bierce shows us many spirits animated by cold and awful revenge, sometimes visible and sometimes unseen, as where a soldier killed for striking an officer answers, "Here!" to the roll-call, just at which moment a mysterious bullet from nowhere strikes the officer through the heart.[129] Crawford sends a drowned sailor back in wet oil-skins to slay his twin brother who has impersonated him to win the girl they both loved. When the two bodies wash ashore one is a newly dead corpse, the other a skeleton in oil skins; while the dreadful rattle of the accusing lump of lead