For over thirty years photographs have been taken in London, on which, when they were developed, figures appeared for the presence of which there seemed to be no physical cause. They appeared both with professional photographers and in private studios. Two or three professional photographers laid themselves out to encourage such appearances. Others were annoyed by them. One in particular, whom I knew personally, was greatly annoyed in this way, fearing it might injure his business. Naturally, but unfortunately, the term "spirit photographs" was invented. Unfortunately, because, granting the reality and genuineness of some of the results, it by no means follows that a "spirit" stood or sat for its portrait, as a human sitter does. Naturally also, various explanations were soon alleged, two being, either that the plates had been used before, and had been imperfectly cleaned, or that the results were produced by deliberate artifice and fraud on the part of the photographer. There is no doubt that artificial results can be obtained in a variety of ways, which are extremely difficult, if not impossible to distinguish from the professed genuine article. It may therefore be said that no examination of a professed "spirit photograph," or as we should prefer to call it, a "psychic photograph," is sufficient to determine its nature and origin. The true test must be sought for in the conditions under which the photograph was taken. Very few of those who have had to do with "spirit photography" have possessed the necessary technical knowledge, and also been sufficiently careful, in the various stages of the process. The result is that scarcely any of the photographs shown as "spirit photographs" possess any evidential value. In common with several other alleged phenomena, but little attention has been given to the subject by scientific men, or by trained experimenters. The most notable exception to this which I am able to quote is that of the late Mr. J. Traill Taylor, who was for a considerable time the editor of the _British Journal of Photography_. The following quotations are from a paper on "Spirit Photography" by Mr. Taylor. It was originally read before the London and Provincial Photographic Association in March 1893, and was reprinted in the _British Journal of Photography_ for 26th May 1904, shortly after Mr. Taylor's death.