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Unfolding Letters

Our culture is changing the way we communicate with each other. We now correspond using phones, fax machines and e-mail in addition to letters. But letters are special things, especially when they are from previous generations and contain a glimpse of history. 

To preserve these documents, it's important to understand how to unfold them. 

Paper is hygroscopic—it reacts to changes in temperature and humidity on the molecular level. Its cellulose fibers are fragile. Folding the paper to insert it in an envelope weakens these fibers. If you try to flatten the paper by bending in the reverse direction or by applying heat, many of the weakened fibers will break and, in a worse case scenario, tear. Fortunately, with a little patience and care, a letter can be flattened without damaging the paper and the writing on the surface. 

Use humidity. The National Park Service has a detailed article on how to relax folds using humidity. Read this article thoroughly. It will spell out the process, the factors to consider and the supplies that you will need.

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National Park Service Conserve O Gram

How to Flatten Folded or Rolled Paper Documents

Or contact the National Park Service, Curatorial Services Division, Harpers Ferry, WV 25425. Phone (304) 535-6410.

Remember that it isn't simply a matter of adding moisture to the paper or of forcing the letter open and ironing it flat!