Probably most people have heard, but seldom at first hand, of unexpected ghosts appearing on plates or films exposed by amateur photographers. On the rare occasions when such accounts can be traced to their source, one usually finds that there is some simple and evident explanation. Streaks and splashes of light on the plates are comparatively common, and are usually the result of the camera, slides, or dark-room not being light-tight; very strange results are sometimes produced in this way. I was once puzzled by a photograph which showed an arch, like a rainbow, across the sky, when it was quite certain that there had been no rainbow in the sky when the photograph was taken. When the result was repeated a few days later, the camera quickly came under suspicion, and was found to have developed a minute pinhole in the bellows. This was sealed up, and the rainbow did not reappear. Many unexplained markings on plates are certainly caused in this or similar ways; but only under very favourable circumstances could an extra face on the plate be so produced. Sometimes unexpected results are caused by an accidental second exposure; but the nature of such a photograph will quickly be apparent. The use of old glass plates may sometimes be responsible for similar results, as has been already explained. But authenticated cases of the appearance of unseen faces in photographs taken in the absence of a professional medium, and which do not show an obvious explanation, are few and far between. The classical example is that of the Combermere photograph, which was published in the _Journal of the S.P.R._, and aroused much discussion and criticism. A Miss Corbet took a photograph of the library of Combermere Abbey, Cheshire, on December 5th, 1891. She was alone at the time, and left the camera during the exposure, as it was a long one. She kept a note-book with records of her photographs, which afterwards showed that an exposure of one hour had been given, namely from 2 to 3 p.m. Unfortunately she did not develop the photograph till eight months later, and was then amazed to find a figure occupying a chair in a prominent position in the photograph. The figure was faint and transparent, the legs being quite invisible; the features were not recognisable; but the presence of a head, shoulders and arm was fairly plain. Inquiries were made, and it was found that not only was the chair in question the one Lord Combermere had been wont to occupy, but that he had died a few days before the photograph was taken, and was actually being buried some two miles from the Abbey at the hour at which the photograph was taken. The photograph was naturally shown to the dead nobleman’s relatives, some of whom professed to recognise it as Lord Combermere. It was further pointed out that he had lost the use of his legs in an accident some three weeks before his death, and that the spirit figure was correspondingly legless!