The following is a post by Dr. Fenella France, Chief, Preservation Research and Testing Division.
Is one library’s copy of a single book in the same condition as another library’s?
With databases like WorldCat, it is easy to track where copies of “identical” books are all over the world, but what about their condition? “Assessing the Physical Condition of the National Collection” (ANC), a multiyear research project in the Library’s Preservation Research and Testing Division (PRTD) funded by the Andrew W. Mellon Foundation, is attempting to look further into this question. The project focus is to compare 500 of the “same” books from five large research libraries across the United States. The books chosen for the project were printed between 1840-1940, a time period when paper manufacturers began innovating the paper making process and changing paper pulp types. In order to take a nation-wide survey, ANC partner libraries are located in five different climatic zones: Arizona State University Library, University of Colorado Boulder Library, Cornell University Library, University of Miami Libraries, and University of Washington Library.
Why might the ‘same’ not be the same?
Our biggest consideration when beginning this project was to determine what impacts library collection materials. Three main factors that influence paper-based collections were identified:
- the inherent properties of the paper, such as its composition and how it was manufactured – things that cannot be changed about the books.
- the environment, like the temperature, humidity, pollutants, and light – things which are possible to control.
- and usage – how often people use, read, and thumb through the pages; a challenge for libraries that can be hard to mitigate, as providing access to collection items is the major role of library services.
ANC aims to determine the current physical state of items held nationally, with the intent of identifying those materials that are in good condition, where they can be found, and informing institutions about the potential risk of loss that might correlate to the main factors affecting collections. PRTD staff is working to compare the physical and chemical properties, as well as optical characteristics of these “same” books to see if we can observe trends in “at-risk” time periods of print or paper types. The ultimate goal is to fill gaps in our knowledge by answering questions on how materials naturally age and decompose, as well as allowing institutions to be able to predict with a strong probability of accuracy good quality and poor-quality copies of books.
How can you determine the condition of a book?
In extreme cases, it is easy to see by eye how a book is faring, i.e. new from the store compared to crumbling papers and broken spines. In order to objectively understand the condition of the materials for those in-between stages, rather than just judging by eye, it is necessary to take a sample for testing. Our five partner research libraries generously allowed us to sample a 3/8” strip from a single page of each of the 500 “same” general collection books.
To minimize impact on the books, numerous physical, chemical and optical test methods have been miniaturized or are non-invasive (they do not require a sample) so we can maximize results from this single strip of paper. For example, we are using a mini-pH test method to determine the acidity of the paper that requires only 0.01g of sample (generally only about one 3/8” square sample). Tiny 3/8” squares of paper are also being broken on the Instron tensile tester to understand the strength of the paper. Through Size Exclusion Chromatography (SEC), we can use just a few micro-hole punches (0.1 mm diameter) of paper to learn the length of the cellulose chains the paper is made from. We then link the results of these minimally destructive tests with non-invasive spectroscopy, via fiber optic reflectance spectroscopy (FORS) and Fourier Transform Infrared (FTIR) spectroscopy, which help us to identify the composition of the paper.
After completing analysis, we use a technique called chemometrics (chemical statistics) to sort the information from the various analyses into clusters, allowing us to identify and observe patterns in paper composition that can be compared to known reference papers from our Cultural Heritage Analytical Reference Material (CHARM). From these reference samples and research, we can see that, in the early transfer from rag to wood pulp in the 19th century, manufacturers were experimenting with the composition of paper. We are intrigued by its potential impact on paper longevity.
What are we finding so far?
Early on, we discovered that the “same” books from our partner institutions are often not the same after all, with some even having different covers, publishers and publication dates. Adding another layer of complexity, we are seeing many volumes that hold multiple paper types in one book. While these material differences are identifiable through analysis, in some instances they are obvious from visual assessments alone. This has us curious about what has caused some pages to age differently even though they have been exposed to the same environmental conditions over time. These observations have inspired further conversations regarding the production process of the books and their pages.
What’s next for the project?
With so much data being gathered from this project, we are working to share the data in ways that collection care professionals can utilize. At present, we are developing methods for portable intuitive collection assessment tools that can take the information from all the analyses and allow users to predict which books are better in quality versus books that might be more at risk, and therefore should be higher in the digitization queue.
Look for further updates in upcoming blog posts!
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