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Harvard College Library News: News from around the libraries

Rare Photograph Uncovered in Houghton Collection

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Elena Bulat, left, and Maggie Wessling, demonstrate the hand-held XRF device used to uncover a rare Kallitype print in a Houghton Library collection.


March 30, 2010 – The discovery of a rare Kallitype print in a Houghton Library collection of historical photographs suggests the long-defunct photographic process may have been more commonly-used than historians believed and that similar prints may be lurking, unidentified, in archival collections, a finding which could fundamentally rewrite scholar’s understanding of the history of photography.

The Kallitype process was invented in the late 1800s as an alternative to making expensive platinum prints. Though briefly popular, it was quickly replaced by gelatin silver prints, which became the dominant photographic process until the introduction of color film in the 1960s. Believed to be the first Kallitype ever identified in Harvard’s libraries or archives, the rare image was uncovered by a photograph conservation team at Harvard’s Weissman Preservation Center while working to preserve a photo taken from the William James Family collection held by Houghton Library. The team that identified the photo was made up of Brenda Bernier, the Paul M. and Harriet L. Weissman Senior Photograph Conservator; Elena Bulat, photograph conservator; and conservation technicians Andrea Youngfert and Maggie Wessling.

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“Elena and I have been working with photographs for many years, but neither of us remembers knowingly seeing a Kallitype in any collection, either at the George Eastman House or at the National Archives,” Bernier said. “This discovery opens a lot of doors, because if we discover that Kallitypes are widely dispersed and we didn’t know it, that will tell us something about the history of photography and about how studios did or did not use this process.”

While the discovery of the rare photo opens new research avenues for scholars, identifying the Kallitype required some detective work from Weissman staff. Initially believed to be a gelatin silver print, the image was one of several which were sent to the Weissman Center for treatment of “silver mirroring” – areas where the silver in the image moves slightly out of place over time, leaving a patina on the surface of the print that some consider disfiguring.

“When we looked at the photograph using a 30x magnifier, we saw that the paper used in the print revealed lots of paper fibers,” Bulat said. “Gelatin silver prints don’t show as many fibers because of the way the prints are processed, so we knew this wasn’t a gelatin silver print.”

The possibility that the photograph was actually a platinum print was also ruled out, because silver mirroring only occurs in images produced using silver. Platinum prints do not use silver.

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The rare Kallitype print recently uncovered by Weissman Preservation Center staff shows William James, right, talking with carpenter Paul Ross.

Having ruled out the most common photographic techniques, the conservation team began researching other, less commonly-used processes, and eventually began to suspect the image might be a Kallitype. Yet some doubt remained, because silver mirroring has never been seen on a Kallitype, and is unlikely to happen given the way the prints are made.

The ultimate proof of the Kallitype hypothesis came from a hand-held XRF (X-ray fluorescence) device. Using X rays, the instrument identifies the metals present in a sample and produces a unique, chemical “signature” for each item. Tests performed on the James family photograph allowed conservators to match its chemical signature to that of a known Kallitype print made by Bernier as part of a project in graduate school.

“This is an important discovery for the library, because we can now identify this image as a Kallitype in our cataloging,” Leslie Morris, Curator of Modern Books and Manuscripts at Houghton Library, said. “It also illustrates the incredibly valuable benefit of having a preservation program. If we didn’t have photo conservators on staff we wouldn’t have learned about this photo. It’s because they bring their own materials expertise to our conservation efforts that we are able to learn something new about our collections.”

“I’m sure there are other Kallitypes in this collection,” noted Morris, who said the discovery came as a surprise. “It looks just like other photographs from that period. This was an exciting moment, when you learn something new about an object in the library’s collections.”

The photo, taken from one of the four James family albums held by Houghton Library, will be included in an August exhibit marking the centennial of William James’ death, Morris said. Organized in conjunction with the William James Society, the exhibition is one of several events which will mark the centennial. Other events include a panel discussion organized by the Division of Social Sciences, and a three-day conference organized by the William James Society. The final day of the conference will include sessions at Houghton and Lamont libraries as well as a walking tour of Harvard’s campus and a stop at the James family home in Cambridge.