Last week we took the Ground Penetrating Radar equipment to Brimlow Farm to try our newly acquired geophysics skills on the area where we had discovered the Roman road in 2004. It may seem a futile exercise to use the machine on a site where we know there to be the remains of the road. It would, however, be very useful to know whether this technique is able to detect this type of feature in clay-soil conditions where we know resistivity proved totally ineffective. These conditions are generally detrimental to the GPR system as well, but maybe the stony surface of the road might provide a good target for the radar to reflect off.
The two fields we have investigated over the years at Brimlow, lie at the north end of Gidlow Lane and straddling the boundary between Wigan and Standish. Despite developer pressure, the farmer, Roy Brandon, has managed to retain the area free from encroaching housing development. However no one knows how long the situation will last as these fields are prime targets for the relentless spread of urbanisation in the outskirts of Wigan. We decided to target the south field with the GPR as this was the one we had particular problems with resistivity. Our excavation in 2004 revealed the road in an area to the south of the pond, where the increased depth of plough soil seemed to give it better protection to the remnants of the road. We therefore planned our GPR survey just south of the previous dig site. Before starting this, however, Roy had told us about an area next to his duck pond where he had observed a square shaped pattern emerge during a dry spell a few years ago. Within the square he had also seen a round feature. This was quite intriguing as there is nothing showing on earlier maps in this area. We therefore decided to explore this region first, as it was easy enough to mark out (especially as I was struggling to re-establish our baseline from 12 years ago). The original baseline, which ran from the corner of the allotment in front of Gidlow New Houses to the apex on the gable of the sheltered housing to the south of the site, was first established in the mid 80's. The problem, of course, is that over the years trees have grown and various obstacles have appear along the sight line, making it really difficult to re-establish the line, but it is essential if we want to relate our findings to previous work.
Our first surveys (a 10m x 10m and a 10m x 20m) on the site next to the duck pond did not reveal the shapes describe by the farmer. However it did show a large linear reading at a depth of between 50cm and 80cm which would be well worth investigating at some point in the future.
Our second survey over the Roman road site (once I'd got a fix on the baseline) did produce some intriguing results (see below) at various depths of between 60cm and 80cm. A very thin feature, running perpendicular to our baseline, looks suspiciously like a field drain. One of the main readings, however, a large reflection in the centre of the scan, looks to be on the right alignment and wide enough to represent the road. This is great news as it suggests that we may be able rely on GPR for other sites with this type of soil condition.
Tribute to a Gentleman
 It was very sad to hear the news last month that Jim Preston had died after a short illness with cancer. Jim and his wife Ruth were long term members of our Society having joined in 1999. Over the years Jim has been very supportive of our group, particularly during the troubled times we had a few years ago when the Society nearly folded. His particularly interest was industrial archaeology and donated DVDs of routes through our industrial heritage, along old paths and disused mineral lines around the Wigan area. However his interests were wide-ranging and in 2011 he even gave us a talk on Chedworth Roman Villa having visited it with Ruth the previous summer. Jim was a true gentleman and will be surely missed all who knew him - our thoughts of course are with Ruth and his family.
Next Meeting
Wednesday 1st Junein the Standish Suite at the Brocket Arms (7.30pm as usual). This month we have Dr Andrew Fear, who is lecturer in classics at Manchester University. He will be coming to give us a talk about Chariot Racing in Ancient Rome. Sounds like it could be very entertaining - hope to see you there, BA.
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