Ann in ambrotype

This photo is of my mother’s mother’s father’s mother’s mother... In other words my great great great grandmother. Ann Gomm was born in 1796 in Milton-under-Wychwood, Oxfordshire. She married Thomas Young (1791-1855) in May 1818. She died in 1880 in Shipton-under-Wychwood. This photo was almost certainly taken between the late 1850s and the mid 1860s when Ann Young, as she had become, was in her sixties.


How can I date the photo so closely? The answer lies in the nature of the print - it is a positive image on glass – an ambrotype. The ambrotype process (from Greek ambrotos, "immortal") is a photographic process that creates a positive photographic image on a sheet of glass using the wet plate collodion process. It was patented in 1854 by James Ambrose Cutting of Boston, in the United States. The wet plate collodion process was invented just a few years before that by Frederick Scott Archer, but Archer used it as a negative.

One side of a glass plate was covered with a thin layer of collodion, then dipped in a silver nitrate solution. The plate was exposed while still wet. (Exposure times varied from five to sixty seconds or more depending on the amount of available light.) The plate was then developed and fixed. The lengthy exposure time is one reason why people tended not to smile. It was easier to maintain a still serious face than smile without moving.


The resulting negative, when viewed by reflected light against a black background, appears to be a positive image: the clear areas look black, and the exposed, opaque areas appear light. This effect is achieved by coating one side of the glass negative with black varnish. Either the emulsion side or the blank side can be covered with the varnish: when the blank side is blackened, the thickness of the glass adds a sense of depth to the image. In either case, another plate of glass is put over the fragile emulsion side to protect it, and the whole is mounted in a metal frame and kept in a protective case. This particular photo has lost its frame and case over the years.

The ambrotype was much less expensive to produce than the daguerreotype, and it lacked the daguerreotype's shiny metallic surface, which some found unappealing. By the late 1850s, the ambrotype was overtaking the daguerreotype in popularity but by the mid-1860s, the ambrotype itself was supplanted by the tintype and other processes.