3. The more usual type of “spirit photograph,” with which this article is chiefly concerned. Here a plate is exposed upon a sitter or sitters, and on development an “extra” appears, varying from splashes of light to fully-formed features or figures. The presence of a medium is usually regarded as being essential for such phenomena; but similar appearances have occasionally been obtained by amateurs on several well-attested occasions, either unexpectedly, or upon plates deliberately exposed for the purpose, no professional medium being present. 4. In some cases the plates are not exposed in a camera, but merely submitted to “spirit influences,” which results in more or less distinct faces, or even screeds of writing, appearing on development. It is not perhaps surprising to find that the spirit photograph originated in America, where it dates back to the days of the wet-plate process. The first recorded case comes from Boston, in 1862. One Mumler, an engraver by trade, made chemistry and photography his hobby; and having among his friends a professional photographer, he was frequently dabbling with plates and chemicals in his studio. Up to this time he had shown no mediumistic tendencies, although it is safe to assume that he must have known something of spiritualism, since this was attracting much attention in America at the time. One day Mumler suddenly produced a photograph of himself, standing, with a chair by his side supporting a shadowy female figure. The face of this figure was not clear, though the upper part of the body was fairly well defined; below the waist it faded away. The chair and background were distinctly visible through the extra. He alleged that this was an untouched photograph, which he had taken by focussing the camera on the chair, inserting the plate, and standing by the chair for the period of the exposure. This picture raised a considerable stir, and Mumler published the following declaration in the press: “This photograph was taken of myself, by myself, on Sunday, when there was not a living soul in the room beside myself--‘so to speak.’ The form on my right I recognise as my cousin who passed away about twelve years since.--W. H. MUMLER.” Not unexpectedly, other people soon wanted their dead relatives to be photographed with them, and Mumler’s services were in considerable demand. Many of his sitters were rewarded with extras, and he soon started a regular business, claiming that he was a medium for taking spirit photographs. His pictures aroused much interest both in America and in this country, and he evidently found it a paying business. The following advertisement with regard to copies of his photographs appeared in the _Spiritual Magazine_ for 1863: “The packet of three photos may be obtained from Mr. Pitman, 20, Paternoster Row; price 3s. 6d.”