In a previous post, we told you that the two wooden heads were going to be X-rayed and CT-scanned, alongside with some other artifacts from the Lab.
In this post we will deal with what we learned about the wooden heads’ eyes from the X-radiographs only.
A lot of our readers will probably know what X-rays are, for they may have experienced them in a hospital. X-rays are also successfully used in Art and Archaeology (for a general overview and some examples, see SCHREINER et al, “X-rays in Art and Archaeology – An overview). The principle of the X-ray is to expose a material to x-ray energy of a particular wavelength. According to the molecular weight of the material, the x-rays will, or won’t, be allowed to go completely through it. The energy that does penetrate passes through to a detector.
In digital radiography, the data is then processed by a computer and, eventually, we obtain a picture where dense (high molecular weight) materials appear white and lighter ones (low molecular weight) are black.
X-ray photograph of E17911 – We can see a lot of termite tunnels and the big hole inside the head, on the right-hand side, and the shining eyes.
E17911, in profile – This picture allows us to see more clearly the structure of the eyes.
E17910 – Also helpful about the inserting of the eyes.
In these radiographs, we clearly see the structure of the inlaid eyes. In fact, those eyes are quite similar to those studied at the Louvre Museum on Kay’s statue (ZIEGLER, Les statues égyptiennes de l’Ancien Empire, Musée du Louvre, 1997, p.256). This statue is from the Vth Dynasty, not so far in time from our heads.
Eventually, we can conclude that the eyes are made of a metallic sheet soldered in the back, which is flat. It is shell-shaped and the hippo ivory is inserted inside. Then the black pupils (made of obsidian?) are placed in the ivory, maintained inside by an adhesive (resin ? plaster ?).
X-ray radiography photograph of Kay’s statue eyes (from ZIEGLER, 1997, p.256).
Structure of Kay’s eyes (from ZIEGLER, 1997, p.259); the back of the metallic part is flat and the edges were folded so as to form the eyelids.
Structure of Kay’s eyes and identification of the materials we have on Adu’s eyes (from ZIEGLER, 1997, p.259)
Fortunately, the Penn Museum has some inlaid eyes in storage, allowing us to figure out more clearly what we have on the heads.
The eye n.E6789B – Limestone and obsidian.
Back of the eye n.E12905A – Copper alloy.
Again, fortunately for us (yes, fortunately!), the Louvre Museum has a very interesting statue, also from the Old Kingdom, with missing eyes. This statue of a nobleman named Tcheti informs us on how the inlaid eyes were inserted into the wood.
Tcheti statue, Louvre Museum n.E11566 – Detail of the missing eyes.
We can see that a hole was cut in the wood, fitting the eyes’ size. We can suppose that an adhesive was used to prevent the eyes from falling off the statue.
As you can see, a conservation intervention, apart from treating the objects, can also allow us to study them more closely and to know them better.
We will talk about the CT-scan in a next post and, in the meantime, you’re more than welcome to visit us at the Lab or to post a comment below !