Frederick Langenheim. Deaf and Dumb Asylum. Philadelphia, 1856. Glass stereograph.
Stereographs harkened the commodification of photography. Issued commercially in England in 1852, the three-dimensional photographs were introduced to the United States in 1854 by Langenheim and his brother William, first in glass and then in paper. The pioneer Philadelphia photographers also marketed lantern slides in America and thus promoted genres of photographs intended to be replicated and shared as opposed to tucked away as unique treasures. By the mid-1870s reproductive techniques that used photography to create a printing plate for use in a press furthered even more the commercial uses of the medium.