Carleton E. Watkins self-portrait, c. 1883, albumen silver print, from the National Portrait Gallery which has explicitly released this digital image under the CC0 license. (<a rel="nofollow" class="external free" href="https://npg.si.edu/object/npg_NPG.2007.123">https://npg.si.edu/object/npg_NPG.2007.123</a>)
Carleton E. Watkins
National Portrait Gallery