Florian Cajori made the first X-ray photographs west of
the Mississippi soon after hearing of Wilhelm Roentgen's accomplishment in
Germany. He apparently read of the work in the February 5, 1896
issue of the local newspaper. The requisite equipment was already
in his lab - a Crookes tube and a Rumkorff coil. Within hours Cajori
was showing x-ray photographs to his advanced physics class.
The hand is either Frank Loud's or a student's.
The foot is Frank Loud's complete with boot nails.