I have no doubt it is the same with the producers or the agents of occult phenomena. Sensory hallucinations may be stimulated. They may be stimulated by intoxication and disease, or they may be stimulated by the morbid conditions of a spiritualistic _séance_. Everything in these conditions--the prolonged darkness, the emotional expectancy--promotes the peculiar frame of mind apparently requisite. Constant exercise--perpetual aspiration develops the power of seeing visions. After a time, in well-known cases, they appear to need no inducement to come spontaneously. One well-known medium, Mr Hill Tout, confesses that building and peopling _chateaux en Espagne_ was a favourite occupation of his in his earlier days. This long-practised faculty is doubtless a potent factor in all his characterisations, and probably also in those of many another full-fledged medium. Hallucinations need not be visual only; they are frequently auditory. Miss Freer gives an account of one induced by merely holding a shell to the ear. There is another case of a young woman in whom auditory hallucinations would be excited on hearing the sound of water running through a tap. Given the basis of actual sound, the hallucinable person quickly causes it to become articulate and intelligible. Thus, is it unreasonable to suppose that the vague, nebulous lights seen at dark _séances_ would furnish the raw material, so to speak, for sense deception? Thus, we have the basis and beginning, from one point of view, of modern spiritualism. But before we examine the question of clairvoyance or trance utterances of spiritualistic mediums we must first of all go into the subject of physical phenomena. * * * * * So-called physical phenomena are a comparatively modern excrescence on the main growth. It is only within the last half-century that they have attained any considerable development. The faith in the communion and intervention of spirits originated before their appearance and will probably outlast their final discredit. At the best, whatever effect they may have had in advertising the movement with the vulgar, they seem to have exerted only a subsidiary influence in inducing belief with more thoughtful men and women.