NWO Team Science Award for research on Hugo de Groot’s Bookchest
An interdisciplinary team of researchers has won the NWO Team Science Award after conducting research regarding the authenticity of several “Hugo de Groot’s” bookchests for the Dutch TV series Historisch Bewijs. The team consisted of researchers from the University of Amsterdam, the Rijksmuseum and CWI, Center for Mathematics and Informatica, in which Joost Batenburg, professor at LIACS, takes part.
Hugo de Groot’s Bookchest
Hugo de Groot was a Dutch jurist and humanist, who is said to have escaped his imprisonment in Castle Loevenstein through a wooden bookchest in 1621. Several museums, including Rijksmuseum in Amsterdam and Prinsenhof in Delft, are in possession of bookchests that are thought to have been used by Hugo de Groot for his escape. In Kunsthistorisch Bewijs, one episode is dedicated to determining which of these chests is the original one. In order to distinguish when the different chests were produced, the team wanted to use a technique called dendrochronology: analyzing the tree rings in the chests’ wood, in order to make an estimate of its age.
A new CT scanning technique
While using the dendrochronology method, the team was faced with several challenges. Firstly, it was difficult to get to the needed sections of the wood, as it had been covered up by other boards of wood, metal and leather. As the chests were highly valued, it was not possible to take them apart. A way to look at the inside of an object without taking it apart, is through Tomopgraphy (CT) scanning. Joost Batenburg is one of the researchers in the team who is specialized in this field. The chests, however, were too big to easily conduct a regular CT-scan, which is why the team decided to look for alternative scanning options. Eventually, the team discovered that the shape of the tree rings would be perfectly visible in images taken along a line direction, while the object is moved sideways. The images captured are then reconstructed through algorithms to create a tomographic image of the transverse section of wood, where the tree rings can be seen well.
A breakthrough in dendrochronological research
Moving an object sideways instead of rotating it, as one would do with a regular CT-scan, was a an approach to CT scanning that had never been used before. By combining knowledge from different disciplines, such as Archeology, Technical Art History and Computer Science, the team has opened up numerous possibilities in the field of dendrochronological research regarding large objects that cannot be taken apart.
Watch the episode of Historisch Bewijs here.