The international team of researchers, led by Jana Dambrogio and Amanda Ghassaei, used a technique they developed called “virtual unfolding” to read the letter, which was sent from French merchant Jacques Sennacques in Lille to his cousin Pierre Le Pers in the Hague in 1697. They used X-ray microtomography scans of the letter to see inside the document in thin slices and grafted those scans together to create a 3D image; then they used flattening algorithms on those scans to “virtually unfold” the letter. After doing so, they learned Sennacques’s letter asked his cousin for a copy of a Daniel Le Pers’s death notice.
This is a major breakthrough for historians and conservators; now, when examining sealed historic letters, researchers won’t have to damage or change the form of a document to learn what’s inside. The document’s original folds and packaging can be preserved.
Said the research team in their paper, published yesterday in Nature Communications, “We could have simply cut these letters open, but instead we took the time to study them . . . letters can be a lot more revealing when they are left unopened. Using virtual unfolding to read an intimate story that has never seen the light of day—and never even reached its recipient—is truly extraordinary.”