By: J. M. Iacchei
A Cornellian, Elsa Guerdrum Allen (1888-1969) was an ornithologist, lecturer, and writer. The Division of Rare and Manuscripts Collections at Cornell University holds a collection of her work: manuscripts, photographs, prints. Selected items from this collection have been brought to the conservation lab for treatment. This box contained 38 beautiful, but tightly rolled and heavily creased, ornithological photostat prints, and two color lithographs, the subject of this post.
The lithograph prints had been rolled and subsequently crushed during storage, leaving them with sharp vertical creases. They were discolored, rather brittle, and contained excessive edge damage and areas of loss. These characteristics heightened the potential for further damage to occur, making the prints unsafe to handle, and therefore inaccessible to patrons and researchers.
Of the two litho prints, I will present you with this one:
The goal of the selected treatment was to prevent further deterioration and make these items accessible by repairing tears, filling areas of loss and stabilizing the paper support with a tissue lining. The basic treatment steps are discussed below:
Washing: During washing, soluble deterioration products that cause papers to become discolored and brittle are reduced. The process can improve the paper’s flexibility and reactivate fiber to fiber bonding, thereby improving strength. The inks were first tested for solubility to determine whether or not an aqueous treatment was advisable. They proved to be stable and we proceeded with washing the lithographs in three successive baths of filtered water at a pH of 8-8.5.
Mending Tears, Filling Areas of Loss, and Lining
If you have ever let a wet piece of paper dry unrestrained, you have probably found that it did not dry flat. If that paper had a tear in it, you may also have found that some distortion occurred during drying-the edges of the tear are no longer in alignment. To reduce the potential for this unwanted distortion, significant tears were mended and areas of loss were filled directly after washing and prior to lining with Japanese tissue and wheat starch paste. The areas of loss were filled using toned Japanese tissue.
Once lined, the print was left to dry under weight between blotter and polyester web. Washing has a tendency to “grey” the support, bringing it closer to its original color. This can be anticipated to some degree, but the fills were a little lighter in color than anticipated. An additional fill was added to compensate. The item was then re-humidified using Gore-tex, and dried under weight. It now looks like this:
In retrospect …
Overall, this treatment was very successful. However, it was not without its challenges and learning opportunities. Alternative methods to filling large areas of loss, choice of lining material, and the use of toned tissue were re-evaluated. After treatment, the larger areas of loss showed some cockling. This is a risk when applying a fully pasted out tissue fill to an area extending the entire width of the document, even when supported with a sheet of mylar. A thicker tissue lining may have helped to reduce the cockling that occurred. Another alternative would have been to fill the larger areas of loss after lining.
The tissue used for the fills and mends was toned with acrylic paints. Once dry, the larger filled areas showed some discoloration. This is possible due to 1)”movement” of the pigment with the application of paste in the lining process or 2) the result of an uneven distribution of paste.
Despite these setbacks, the lithographs, along with the other contents of the box have been stabilized and rehoused. The beautiful imagery that was once too fragile and unstable to be unrolled is now accessible to patrons and researchers to view.
If you are interested in ornithology, or birding, and have not found it already, you may enjoy visiting The Cornell Lab of Ornithology.