Portrait of John Torrey
Photographer unknown
ca. 1840
Quarter plate
Gray Herbarium (1202)
(GH-3)
Photographer unknown
ca. 1840
Quarter plate
Gray Herbarium (1202)
(GH-3)
Daguerreotypes are
unique images created by a direct-positive process that produces no original negatives. Thus
the preservation of these unique images becomes critical if their availability for future
research is to be ensured.