Davidson College, a four-year liberal arts college located in Davidson, NC, is using a flexible and portable technology from Digitome Corporation for taking three-dimensional x-radiographic examinations of various archaeological objects. The Digitome software constructs a volumetric display of an imaged object using multiple images of the object from different perspectives. Typically, a 3D exam is constructed from around eight images of the object.
This technology has potential applications in art and object conservation, archaeology, and other fields requiring non-destructive testing. Over the summer of 2014, Dr. Dan Boye (Professor of Physics, Davidson College) and I, (Ryan Kozlowski, Davidson College class of 2016) applied the Digitome technology to archaeological artifacts from the Queen Anne’s Revenge (QAR), the flagship of infamous Blackbeard the Pirate. This research was funded by the Davidson Research Initiative. The QAR Conservation Laboratory, located in Greenville, NC, is a part of the North Carolina Department of Cultural Resources (NCDCR).
Students in Davidson College’s physics department have been examining artifacts from a long-ago grounded ship off the North Carolina coast that state officials say was Blackbeard’s Queen Anne’s Revenge. But this isn’t a treasure hunt.
For them, the prize is in the discovery – uncovering clues about life in the early 1700s, perhaps even solidifying evidence that these are indeed pieces from Blackbeard’s ship – and in the chance to gain and share knowledge in many fields based on what they’ve learned from new technology.
At first glance, this painting appears to be quite normal. However, on closer inspection you begin to see faint signs of another woman who has been hidden and painted over. The bottom of her skirt is starting to show under the top layer of paint near the bottom, and when you look at the painting with a slight glare (as we did in this picture) you see the ghost of a face next to the woman in profile. Who changed the composition of this painting? Why was the original woman painted over?
Older oil paintings are made with paint mixed from metals, which will show up in an x-radiograph. To investigate this mysterious woman, we took a traditional x-ray of the painting. Because we do not see the overpainted woman in the x-radiograph we believe that she was added using different paints that either do not include metals or include metals like zinc and copper which do not always appear in x-radiographs. Her face does not appear to be painted by the same hand that painted the seated man.
The x-radiograph shows that the two women have different styles of clothing, are facing different ways, and are engaged in different activities. The original woman has a lower neckline and a different style of collar, as well as a different hat. If you look at the bright dots on the x-radiograph, they line up with the pitcher on the table and the vase above the man. This leads us to believe that she is holding some type of container above the man’s glass. The original woman is closer to the man and is interacting with him, while the overpainted woman is in the background slightly behind the doorframe.
To discover more, a near infrared picture was taken that shows other aspects of the original woman. We can see her face more clearly and can tell that she is facing the man. The bottom of the pitcher she is holding is visible. We see that the man has not been changed from the original.
With x-rays and infrared radiation, we can see much more of the original painting. This new knowledge makes one wonder what the reasons behind the change are. Was the original woman the man’s wife or just a maidservant? Did the owner’s view on the role of women in general change?
We would like to acknowledge Professor Ruth Beeston of Davidson College Chemistry Department for directing us to this as an example of an underpainting and for her help with the infrared reflectography.