One of the ongoing research agendas with the Stanford group is Binchester Kiln Project. This is part of a broader initiative that is exploring ceramic technology, aiming to get to the human experience of making in clay. We are funded by the Stanford Presidential Fund for Innovation in the Humanities, by the Metamedia Lab and through the generosity of a donor. We set out last year to make a replica Romano-British kiln on campus as a practice run for a similar kiln to be built on site in England, at Binchester. Ideally, we will make a pottery kiln that is an exact duplicate of one that we find at Binchester. Based on the results of the geophysical survey, it is likely we will find one this summer. In the meantime, we constructed a kiln on campus that is a composite of several key features found in Late Iron Age and early Roman kilns of Britain.
In mid-January, we fired our Stanford Binchester Kiln for 19.5 hours to bake about 40 pots, which were made by the Ceramics Club and the student-run Ceramics studio on campus. Over this period, we weighed wood in a bucket suspended from a ladder and took temperature readings using a digital data logger with 3 thermocouples: two positioned in the ware chamber and one between the layers of sod over the fire tunnel.
Using a mixture of hard woods and wood from fruit trees, we sustained a high temperature of about 950º Celsius that was achieved about 15 hours after ignition. Students and volunteers stayed late into the night, and a few into the early morning as the dew began to settle on our grassy kiln.
We let the kiln cool for about 30 hours before opening it up. The sod covering the ware chamber cracked and crumbled in our hands. All of the 40 pots survived, although some had experienced some heat warping. The wall of the kiln, with no clay lining other than the clay matrix of the mound, sustained some cracking but no spalling, which was good for the pots. However, these cracks might need to be repaired before our next firing.
A few of the pots in the mix, such as the orange one in the foreground of the photo below, were made with clay we shipped back from a clay mine near Binchester. As luck would have it, the world’s largest brick manufacturer, Wienerberger, has a brick factory about a mile from the site and has been an enthusiastic supporter of the kiln project. Taking the lessons we learned from our experience at Stanford, we will design and build our Durham Binchester Kiln over the next few field seasons. With access to all the geologic strata of clay in the region, including the clay available in prehistory, we will continue our experimental work in the acquisition and transmission of craft knowledge.
For more information about the construction process of this kiln and continuing research, please visit the Burnt Earth Blog at http://burntearthblog.wordpress.com.