To reveal the erased words on the palimpsests, the researchers photograph each page 12 times while it is illuminated with different-colored visible light, ultraviolet light, and infrared light. Other images are taken with light shining from behind the page or off to one side at an oblique angle, helping to highlight tiny bumps and depressions in the surface. Together, these photographs help reveal the minute traces of ink left on the pages after they were erased or the scratches left by a scribe’s quill. Computer algorithms then analyze and combine the images so the text on top can be separated from the words below.
Over five years, the researchers gathered 30 terabytes of images from 74 palimpsests—totaling 6,800 pages. In some cases, the erased texts have increased the known vocabulary of a language by up to 50 percent, giving new hope to linguists trying to decipher them. One of the languages to reemerge from the parchments is Caucasian Albanian, which was spoken by a Christian kingdom in what is now modern day Azerbaijan. Almost all written records from the kingdom were lost in the 8th and 9th century when its churches were destroyed.
“There are two palimpsests here that have Caucasian Albanian text in the erased layer,” says Michael Phelps, the director of the Early Manuscripts Electronic Library and leader of the project. “They are the only two texts that survive in this language ... We were sitting with one of the scholars and he was adding to the language as we were processing the images. In real time he was saying ‘now we have the word for net’ and ‘now the word for fish.’”
Another dead language to be found in the palimpsests is one used by some of the earliest Christian communities in the Middle East. Known as Christian Palestinian Aramaic, it is a strange mix of Syriac and Greek that died out in the 13th century. Some of the earliest versions of the New Testament were written in this language. “This was an entire community of people who had a literature, art, and spirituality,” says Phelps. “Almost all of that has been lost, yet their cultural DNA exists in our culture today. These palimpsest texts are giving them a voice again and letting us learn about how they contributed to who we are today.”