By Heather Hamilton, Conservator
When faced with damaged or fragile books, conservators have several approaches they may take. A damaged book might be conserved by repairing a binding that is breaking. The covers may need to be replaced with new ones or the text block may have to be resewn. These treatments are intensive and time-consuming. At any given time, libraries and archives will have many books in need of conservation, and not every volume can be considered for full treatment. Another preservation option is to create custom enclosures for books. A common book enclosure is the phase box.
The term “phase box” has been in use for a long time, but it is often a misnomer. “Phase box” indicates that the book will be placed into the enclosure until the time comes when it can be more fully repaired.
However, many books remain in their phase boxes long-term, and that is a good thing, especially for leather bindings. Leather is inherently unstable over time. It becomes brittle and can develop red-rot, the dusty red powder we are familiar with on old leather books. Brittle leather is prone to breaking on the book’s hinge, where it flexes for opening. The leather spine piece, where a book usually has its title, will often break away from the binding when the hinges have failed. These damages can be repaired by replacing the damaged spine with new leather, but the replacement leather will age eventually as well. Nevertheless, leather rebindings and leather repairs are used by conservators. They are appropriate when a book’s binding is of particular artistic or historical significance. Book conservators are trained in historic methods and can repair or replicate leather bindings to restore the original appearance.
To build a phase box, the book’s length, width, and thickness are measured precisely in a measuring device made just for this purpose. Using these dimensions, two lengths of acid-free board are cut and folded to match the book. When the fit is just right, the book will be snug and will not shift inside the box.
There are a number of other protective enclosures used for library and archives collections. A clam-shell box is made much like a book binding and is usually covered in book cloth. These attractive and strong boxes are often made for high-value books. A portfolio with a four-flap enclosure inside can be used for thinner, lighter-weight books.
Phase boxes can be used for more than bound materials. Here at TSLAC, our historic photographs (daguerreotypes, ambrotypes, and tintypes) are housed in individual phase boxes within a storage cabinet. The enclosures protect these glass and metal plates from physical damage and limit direct handling.
What about preserving family artifacts?
Protective enclosures are used in libraries and archives, but they are also appropriate for preserving family artifacts such as scrapbooks, family Bibles, and other bound volumes. For family documents that are unbound sheets, like photographs or certificates, another housing system is preferable. Place documents, unfolded whenever possible, into archival paper folders. Don’t overfill them. Place groups of folders into archival boxes. Choose a box that fits the folders well. If the folders are placed vertically and there is extra space in the box, fill it in with wadded-up, acid-free tissue so that folders do not fall over. Boxes and other archival supplies can be purchased from online stores. Look for high-quality, acid-free materials and comparison shop to make sure you are not over-paying for these specialty items.
More tips on preservation from the State Archives here: https://www.tsl.texas.gov/arc/preserve/index.html