Merry wrote in with a question about marks on an ambrotype:
I’m doing some photo detective work of my own–if I have a cased, sealed ambrotype with a stamped mat (E.R. Perkins), can I assume that the photographer was probably the person stamped on the mat? That might help me narrow down where the picture was taken, right?
Congratulations on researching your photos! If you have a cased image such as an ambrotype with a stamped mat you’re right to assume that identifies the photographer. An excellent resource on photographers in the daguerreotype era is John Craig’s Daguerreian Register. There is an Elijah R. Perkins listed who worked as an ambrotypist from 1856 to 1860 in Newburyport, Massachusetts. He was in Salem, Massachusetts in 1859.