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Letter to Mrs. Morrisson: Part 2

Karissa Muratore was the Willman Spawn Conservation Intern in the summer of 2017. She now attends the Winterthur/University of Delaware...
Conservator mends letter
Fig. 1: Mending letter. Photo by Anne Downey.

Last time we spoke, I was introducing you to a 19th-century letter in need of treatment. Due to the planned use of this object in the American Philosophical Society’s exhibition, Curious Revolutionaries: The Peales of Philadelphia, there was incentive to improve the object’s long-term stability in addition to its aesthetics. Old mends caused uneven discoloration, and iron gall ink threatened to further deteriorate the paper support due to the presence of free Fe2+ ions. A safe washing system could remove or reduce soluble deterioration products, help release old mends, even out the paper’s tone, and remove free Fe2+ ions, but testing had to be done first.

Conservator washing letter
Fig. 2: Washing the letter. Photo by Anne Downey.

Due to the fact that the letter had a variety of different materials, including letterpress ink, iron gall ink, graphite, and watercolor, it was necessary to make sure that if we washed the letter we wouldn’t accidentally wash away original material. After multiple tests and guidance from Anne I decided on a 25/75 DI water/ethanol bath. I monitored the stability of the various media closely during the bath. Happily, everything stayed put, and I was able to mend the losses, tears, and weak areas with thin but strong Asian paper. Afterward, I humidified and gently flattened the letter, and then used colored pencils to tone the still visible stripping caused by the old mends. Toning with colored pencils is completely reversible, and I only toned the front of the letter, since that was the side that was going to be visible during the exhibition. Overall, I am very pleased with the results. Not only does the letter look nicer and feel nicer in the hand, but I hope it will also have a much longer life at the APS because of this treatment.

Letter before treatment
Letter before treatment.


Letter after cleaning
Letter after treatment.



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