The phenomena are usually phenomena of sight, or sound, or both. As a rule the sounds are footsteps, rustling of dresses, knocks, raps, heavy bangs, noises as of dragging heavy weights, and of disarranging heavy furniture. These sometimes occur freely, where nobody can testify to having _seen_ anything spectral. Next we have phantasms, mostly of figures beheld for a moment with 'the tail of the eye' or in going along a passage, or in entering a room where nobody is found, or standing beside a bed, perhaps in a kind of self-luminous condition. Sometimes these spectres are taken by visitors for real people, but the real people cannot be found; sometimes they are at once recognised as phantasms, because they are semi-transparent, or look very malignant, or because they glide and do not walk, or are luminous, or for some other excellent reason. The combination, in due proportions, of pretty frequent inexplicable noises, with occasional aimless apparitions, makes up the _type_ of orthodox modern haunted house story. The difficulty of getting evidence worth looking at (except for its uniformity) is obviously great. Noises may be naturally caused in very many ways: by winds, by rats, by boughs of trees, by water pipes, by birds. The writer has known a very satisfactory series of footsteps in an historical Scotch house, to be dispelled by a modification of the water pipes. Again he has heard a person of distinction mimic the noises made by _his_ family ghosts (which he preserved from tests as carefully as Don Quixote did his helmet) and the performance was an admirable imitation of the wind in a spout. There are noises, however, which cannot be thus cheaply disposed of, and among them are thundering whacks on the walls of rooms, which continue in spite of all efforts to detect imposture. These phenomena, says Kiesewetter, were known to the Acadians of old, a circumstance for which he quotes no authority. {140a} Paracelsus calls the knocks pulsatio mortuorum, in his fragment on 'Souls of the Dead,' and thinks that the sounds predict misfortune, a very common belief. {140b} Lavaterus says, that such disturbances, in unfinished houses are a token of good luck!