Thursday, 10 October 2013

Report: By Director Kurt - What did we find in Trench 1?

From an early stage, the gravel surface at the south end of the trench and the alignments of large stone blocks in the middle of the trench seemed good candidates for the Roman street with timber building to one side that were indicated on the 2011 geophysical survey. However, the stony layer overlying the building contained post-medieval as well as Roman pottery, and the use of such large, if not massive, stones as a foundation was in contrast with the foundations evident in Trenches 2 and 3. Overall, this left a nagging doubt that we were dealing with a relatively recent building that happened to follow the Roman alignment.

However, two further layers of rubble, with distinct dumps (barrowloads?) of cobbles, stone and shale fragments contained only Roman pottery. Furthermore, similar deposits appear to continue beneath the building, which suggests that infilling of the ditch as its fills settled had been a long process. The current interpretation is that the massive blocks are the foundations for a timber building, perhaps of two storeys, with the rubble forming a bed for earth floors that have been removed by ploughing.

Although it is assumed the building extended to the edge of the street as is usually the case, the massive blocks as found were restricted to the rear part. It is suspected that the blocks had subsided into the fills of a large east-west ditch that became disused before the building was constructed. The blocks (and associated rubble layers) appear to have been an unsuccessful attempt to form a solid base for the building on the unstable ground. The front of the building, on firmer ground, may have had much slighter footings or even been built with earth-fast posts, and we hope to find evidence of this next year. 

An alternative theory is that large stone blocks also formed the foundation of the front of the building. If so, as these blocks would not have settled into the ditch they would have obstructed ploughing, and may even have protruded above the ground surface. Consequently they would have been removed, presumably for re-use elsewhere. If so, we will find only a gap in the building construction marking the absent stones. Either way, there is the exciting possibility of finding a large ditch beneath the building next year.

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