How an 800-Year-Old Library Preserves Its Books from Mold and Bugs

Old books are being preserved at Japan's oldest school and perhaps oldest library in a manner I had not seen before. The founding dates of the school and library are unknown, but it is believed that the library dates to the 12th century, the school earlier. Currently, it holds 17,000 volumes, including some that are very old. Presumably, they have some experience with preserving books though I don't know how long this practice has been used.

The Ashikaga Gakko (school), north of Tokyo, airs out their books once a year. This is to protect them from mold and bugs. They take a group of books from the library, in this particular group 53, and lay them out on the floor of an adjoining room. Staff members don face masks and gloves. They then proceed to open the pages, one-by-one, to expose them to dry air. If it is a rainy day, they take a pass. They also check out the bindings for any damage. The process goes on through October and November until all the old and valuable books have been aired out.

Do any libraries in America do this? Some collectors apparently air out their books on occasion but I don't know if this is done by any with seriously valuable books. The major libraries are climate controlled and presumably this is sufficient to discourage mold and bugs. Airing out may be a low-tech way for a library without the funds to provide advanced climate controls.

One obvious downside of this method is that the books are being opened and the pages turned once a year. The reality is every time a book is opened and the pages turned, it suffers some damage, even if miniscule and unnoticeable. Add that up for a few decades, even centuries, and the book is unlikely to be quite the same. This is why major libraries consider their most valuable volumes untouchable. Maybe once in awhile they will open one to a page and put it in a display case, but don't expect to get any closer.

Still, if you have books of medium value, but don't have perfect climatic conditions in your house, this might be a good idea. But, I'm not an expert on this, so here is some advice from the people who have to know – the Library of Congress.