Mr. Crawford, a mathematician and engineer of Belfast, has published reports of investigations of table-lifting seances, and builds up a theory of spiritual cantilevers which he believes to explain his results. The theory is pretty and the diagrams are impressive, but the facts first call for examination. Reading his accounts, I find that the experiments are carried out in a dim red light, for a sudden white light causes the immediate cessation of the phenomena. In addition there is a sacred line between the medium and the levitated table which must not be investigated on pain of dreadful results to the medium. This threat of physical evil to the medium if the sceptic should investigate at a crucial point is a common pretext, but though sceptics have often taken the risk, and seized a spirit to discover a disguised medium, there is no record of such disastrous results as Mr. Crawford would have us fear. I suggest that this investigator should use his technical knowledge to show how a simple but material cantilever, operated by the medium along the sacred line, can produce levitation of the table. The complaint is made that scientific men scoff at spiritualism and yet refuse to investigate it; in the last two examples we see why this is inevitable. Investigation is prevented in each at the very point where fraud might be detected; so long as such obstruction is maintained the spiritualists are likely to continue their complaints, and one must be content to speculate on the mental state which allows a few men of scientific training to support their claims. The reader must not think that my aim is to convert spiritualists from their belief. It is, as I have tried to show in earlier chapters, useless to attack rationalisations in an effort to penetrate a logic-tight compartment; as soon as one defence is broken down another is built up, and one can only take comfort from the history of other examples of _Pseudodoxia Epidemica_, as Sir Thomas Browne (he himself being, strangely enough, an active believer in witchcraft) called them, and look forward to the fading away of this delusion. Just as the belief in witchcraft passed away from the educated and intelligent, lingering only amongst the ignorant, so this delusion will pass and leave our descendants to wonder how some of us came to be its victims. CHAPTER XIII THE EVOLUTION OF THE MEDIUM After meeting my first medium I came away with the feeling that he was a rather artful liar; but now, whilst retaining that opinion, I am ready to admit that perhaps his lying was not a product of his consciousness. I know nothing of his history, but he was accepted by intelligent people as honest and respectable; moreover, records of spiritualism contain so many examples of people whose belief in their own supernatural powers must be accepted as real in spite of manifest deceit, that we must again fall back upon dissociation to explain their state of mind.