William Mumler sells the first spirit photographs
1861
Mumler, a Boston engraver, produced what he described as an accidental self-portrait showing his dead cousin, and turned spirit photography into a business serving families bereaved by the American Civil War. He was tried for fraud in New York in April 1869; P. T. Barnum testified against him and had the photographer Abraham Bogardus fake an image of Barnum with Lincoln's ghost to show how easily it was done. Mumler was acquitted because the prosecution could not prove the method beyond doubt. His best-known image, showing Mary Todd Lincoln with a spectral Abraham Lincoln, is variously dated; Mumler himself later said February 1872.
Source: Wikipedia
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