Dr. Theodor Hansmann (1821-1912) was a physician and Spiritualist from Washington, D.C. He is reported to have served as a medical advisor to President Abraham Lincoln. He had many sittings with celebrated spirit photographers and mediums. He gained notoriety for having his photograph taken with famous spirits such as John Wilkes Booth, Robert E. Lee, George Washington, and Abraham Lincoln.
An article in The New York Harold describes Hansmann’s photographs as follows:
“Dr. Hansmann’s collection of ‘spirit’ photographs is most interesting. There is one with the face of the Empress Josephine, and on the same plate is the head of Professor Darius Lyman, for a long time Chief of the Bureau of Navigation. The head of the Empress Josephine has a diadem around it, and the lights and shadows remind one of the well-known portrait of her. On another plate are Grant and Lincoln. Among his other photographs Dr. Hansmann brought out one of a man who was described to me as an Indian agent. Around his head were eleven smaller ‘spirit’ heads of Indians. In looking at the blue print closely it seemed to me as if I had seen those identical heads— the same as to light, shade and posing—somewhere before.”New York Herald – Nov. 9, 1895
Hansmann frequently worked with William M. Keeler. In one experiment Keeler and Hansmann both setup their own camera, provided their own plates, and took a photograph of Hansmann. The resulting photographs both contained the same materialized spirit, one article stated “this experiment is remarkable”.
 Religio-Philosophical Journal – October 6th, 1898.