"The matter was very simply done. Mr. Dinwiddie asked one of the ladies from the office to come in, and, she consented to pose as a spirit. She was placed before the camera at a distance of about six feet, a red background was given her, so that it might photograph dark, and she was asked to put on a saintly expression. This she did, and Mr. Dinwiddie gave the plate a half-second exposure. Another head was taken on the other side of the plate in much the same manner. After this was done the other or central photograph was taken with an exposure of four seconds, the plate being rather sensitive. "The plate was then taken to the dark room and developed. The negative came out very well at first, and the halo was put on afterward, when the plate had been dried. The halo was made by rubbing vignetting paste on the back, thus shutting out the light and leaving the paper its original hue. The white shadowy heads which are frequently shown in black coats, and which the mediums claim cannot be explained, are also done in this manner with vignetting paste, the picture being afterward centred over these places, which will be white, the final result showing soft and indefinite, and giving the required spiritual look. "Mr. Dinwiddie did not attempt to produce the hazy effect, but this is very easily accomplished in the photograph by taking the spirit heads a trifle out of focus. He claims that all of these apparent spiritual manifestations are but tricks of photography, and ones which might be accomplished by the veriest tyro, if he were to study the matter, and give his time to the experiment. It is only a wonder that the mediums do not do more of it. "The photograph mediums have always claimed that they were set upon by photographers for business reasons, but Mr. Dinwiddie is employed by the government and has no interests whatever in such a dispute." [Illustration: FIG. 30--SPIRIT PHOTOGRAPH BY PRETENDED MEDIUM.] The eminent authority on photography, Mr. Walter E. Woodbury, gives many interesting exposes of mediumistic photographs in his work, "Photographic Amusements," which the student of the subject would do well to consult. Fig. 30, taken from "Photographic Amusements" is a reproduction of a "spirit" photograph made by a photographer claiming to be a medium. Says Mr. Woodbury: "Fortunately, however, we were in this case able to expose the fraud. Mr. W. M. Murray, a prominent member of the Society of Amateur Photographers of New York, called our attention to the similarity between one of the 'spirit' images and a portrait painting by Sichel, the artist. A reproduction of the picture (Fig 31) is given herewith, and it will be seen at once that the 'spirit' image is copied from it." 5. Thought Photography.