Just been on the National Anthropological Arhives of the Smithsonian Institution web site, where I came across the portrait of Silas Jefferson. The photographer was Charles Milton Bell and was taken in the year 1877. Take a look at the title of the photograph:
Portrait (Front) of Ho-Tul-Ko-Mi-Ko (Chief Of The Whirlwind), Called Silas Jefferson, Interpreter (Mixed Blood) 1877.
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