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Damage in Special Collections: Risks Revealed Weissman Preservation Center Harvard University Library June 2007.
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Damage in Special Collections:Risks RevealedWeissman Preservation Center Harvard University Library June 2007
Motivated by heightened interest worldwide in the conversion of library resources to electronic form, the Weissman Preservation Center has compiled a number of photographs that illustrate the important relationship between imaging and the conservation of important library and archives collections. The images that follow suggest the risks that should be addressed before rare and unique materials of significance are handled extensively or produced.
Media on parchment (ink or paint, for example) is prone to degradation. Shown here is an enlarged view of a single stroke of a pen. Flakes of ink are loosely adhered to the surface of the animal skin and pop off with little provocation. Even minor disruption can cause irreversible damage. • This problem can be resolved by consolidating the media (readhering it), and then reproducing the documents carefully using methods suitable to parchment. MS Eng 886.2 Izaak Walton Will, 1683, Houghton Library
Media loss also affects paper-based materials. The corrosion of iron gall ink, for example, leads to breaks in paper supports, many of which are not readily visible. Fine webs of damage eventually connect, and paper falls away. • Flexing of deteriorating paper during handling increases the likelihood of damage. • Physical stabilization involves reinforcing damage without obscuring text or accelerating corrosion. MS Keats 4.3.7 Letter to Joseph Severn, 1821, Houghton Library
Vulnerabilities and damage may not be visible without magnification. • Note, for example, the bottom-most figure in this illuminated page. MS Richardson 42 De Buz Hours, Ca. 1415, Houghton Library
A detail from this image shows the limitations of casual observation. • At a distance the eye completes the deteriorating areas of hair and beard, where pigment is cracking and breaking away. Magnification reveals this decay. • Residue from blue pigment (below beard) hides near-complete losses. MS Richardson 42 De Buz Hours, Ca. 1415, Houghton Library
Careful examination of objects is essential. • The loss of white pigment, for example, may be masked when it occurs over white parchment. MS Richardson 42 De Buz Hours, Ca. 1415, Houghton Library
MS Richardson 42 De Buz Hours, Ca. 1415, Houghton Library
Here the light touch of a cotton swab reveals delicate, friable media. MS Richardson 34, Book of Hours, 15th C., Houghton Library
Working under a microscope, pigment or ink can be re-adhered, using a fine brush to apply adhesive beneath loose flakes. MS Eng 886.2 Izaak Walton Will, 1683, Houghton Library
Some powdery media can be consolidated by applying an organic adhesive carried in an ultrasonic mist. MS Richardson 34, Book of Hours, 15th C., Houghton Library
Fragile, weak bindings can be damaged easily when opened and manipulated to accommodate imaging. • Although this volume reveals deterioration that signals vulnerability, the fragile nature of many bindings is typically hidden beneath leather or other covering material. • Careful examination of problem volumes like the one here, followed by stabilization and proper physical cradling and handling can make safe imaging possible.
Volume safely cradled for copy photography at HCL Imaging Services.
Modern materials are also susceptible to media and structural breakdown. • Here, for example, is an example of a fragile, easily damaged illustration in an important 19th century volume. Note the powdery blue pigment. Typ 820.10.7582 Farben-Kugel, 1810, Houghton Library
Modern pigments are also susceptible to flaking. “Handwritten Selections from the Koran” by Pao Ming Chen Ching Yang Cheng Jung, calligrapher, 1863 Harvard Yenching Library
Graphite in modern manuscripts is easily smudged during handling and must be treated carefully. MS Keats 2.2, Severn Sketch Book, Houghton Library
Even modern inks, as shown in this lithograph, may be prone to deterioration, flaking, and media loss if not conserved and handled appropriately. *43-847F Histoire d’Angleterre, 19th C wooden puzzle, Houghton Library
Stiff binding structures are also at risk during reproduction. • Opening a volume like this one too widely during reproduction can result in broken leaves and sewing thread. • Potential problems can be avoided by providing special structural support for the volume during imaging.
** Text about high-quality cradle set-up during imaging • ** The measures that can be taken • ** Include the beautiful image of the manuscript prepared for photographing.
Close examination of aging materials by conservators, followed by stabilization or full conservation treatment as needed — coupled with careful handling by photographers and skillful cradling and lighting, makes safe imaging possible. • Fragile library materials can be made available to a worldwide audience, and this work proceeds daily in the Weissman Preservation Center (Harvard University Library) and Imaging Services (Harvard College Library). MS Typ 443 Emerson-White Hours, ca. 1485, Houghton Library
Thea BurnsHelen H. Glaser Conservator • Jan Merrill-OldhamMalloy-Rabinowitz Preservation Librarian • Alan PugliaConservator for the Harvard University Library • Pam SpitzmuellerJames W. Needham Chief Conservator for Special Collections Harvard University Library Weissman Preservation Center June 2007