Conserving Harrison's Words
The IHS Conservation Lab has recently been reviewing the conservation needs of the entire Harrison Collection, which includes both manuscripts and printed documents. To create an initial conservation condition survey, conservators examined each piece for physical problems such as tears, soiling, damaging tapes and acidic mount boards. Conservator Susan Rogers and Conservation Technician Elise Calvi are working on the collection
Our newly acquired 1812 Harrison letter to William Eustis needs some attention from the conservation lab as well. An initial examination in the lab produced evidence of some unusual visual characteristics such as erasures, a watermark and evidence of a missing second section of the document, which may provide a tantalizing mystery for further research.
The Harrison Collection items were composed on rag-fiber papers in either printing inks or manuscript inks of the period. Printing inks were manufactured chiefly from carbon black and boiled oils. Manuscript inks were often hand-formulated mixtures consisting mainly of iron filings, pulverized oak galls and whatever liquid was available at the time and place. For this reason, battlefield inks can be particularly unstable, and most iron-gall inks need conservation attention because of their acidic nature. Aging ink acids can burn through paper layers, causing the cracking and flaking away of vital script.
Soiled Harrison papers will first be dry cleaned with shredded polymer. Once cleaning has taken place, any torn or cracking areas of the paper can be stabilized with specially formulated adhesives and hand-made tissues. Since old transparent tapes and animal glues can fail or cause staining, they will be removed with solvents and enzymes. Documents will then be re-repaired with safer materials. Once treatments are complete, the documents will be protected by rehousing them in archival folders, acid-free interleaving and polyester film sleeves.