Even more exciting? There are thousands and thousands of books sitting in libraries, personal collections, and book stores ripe for this treatment.
What’s new here is the technology. Scholars have known for a long time that early modern book production used cartonnage (layers of linen or papyrus) composed of fragments of older discarded manuscripts to strengthen the bindings of books. Kwakkel told The Guardian that as many as one in five books produced between the 15th and 18th centuries was made this way. The same technique was used seventeen hundred years earlier by Egyptians, who used manuscripts as papier mache to construct mummy masks for use in the burial of the dead. We knew the documents were hidden in the bindings of the books, but getting them out meant dismantling or destroying ancient historical artifacts.
This new technology, though, allows scholars to read the fragments in the bindings without dismantling the books themselves. It uses macro x-ray fluorescence spectrometry (MA-XRF) to detect iron, copper, and zinc in the medieval ink. Professor Joris Dik, of the Delft University of Technology in the Netherlands, developed this new process. In 2011 he used it to discover a previously unknown self-portrait of Rembrandt underneath another work. The discovery cleared up the questions that surrounded the painting’s attribution and value.