Day 3 of the Stroud 'Big Dig' 2017
I was twitching a bit last night at the thought that we had a lot of people expected at Stroud today and I did not know for sure that Carl would be able to get the resistivity machine working because of the battery problems. I was dreading having to cancel at short notice. Of course I needn't have worried; the new batteries worked fine and lasted us all day.
We started off keen to finish the resistivity scans in the grid squares in the villa field that we had been unable to finish yesterday. This we duly did whilst the magnetometry team raced off round the corner to do another part of the field between Myrtle Farm (Ellis and Pam) and the New Buildings Farm driveway. This is of interest because it is on higher ground (so less likely to have been marshy in Roman times), is not far from where we found the Neolithic axe head last year and we also thought we might find traces of a building shown on a copy of a tithe map from the 1830s that Ellis and Pam have shown us previously. So far no copies of the geophys rush results from Carl this evening, so I am still in the dark.
At tea break I put the drone up to look for parch marks at the field end of Finchmead Lane. This is one of the images, looking down vertically from an altitude of 120 metres:
You can see a parch mark from the underground drainpipe that runs due south from the end of Finchmead Lane, but I am bemused by the sheep tracks. Why do they always follow each other along these tracks, and why do they always run close past any post, whether concrete boundary post or power pole? You can also make out all the mole hills and all the very prickly thistles.
Also during tea break I got into an interesting email exchange with David Staveley, whose blog posts at http://geophyswithsnuffler.blogspot.co.uk/ about his ground-penetrating radar and geophysics I always find fascinating. We were sharing theories about the trackways at Stroud we are going to be investigating next weekend.
Here is a drone's eye view of morning tea break, with me on the left doing the flying:
Seen here is the magnetometry machine, which has behaved impeccably unlike its resistivity counterpart:
Fighting their way through all the thistles in the villa field while using the resistivity machine, with new member Jason on the left:
Donna and Lyn doing the magnetometry dance, with Butser lurking under the clouds in the background:
Trying to avoid the mole holes while doing 'res' next to Myrtle Farm:
The welds on the bracket have finally given way and the logging unit is only held onto the resistivity machine (upside down) by the cable ties I scrounged:
Finally, a salutary health and safety lesson today for me. I was wearing an old pair of gardening shoes today because I could not be bothered to go back to the car to get my boots. I managed to put the spike of the resistivity machine through the toe of my shoe, narrowly missing my big toe. I was lucky. Next time I pay attention to my own risk assessment and take the trouble to wear my protective footwear!
On the way home I met Jeremy Mitchell who says he is looking forward to seeing us do test pits in his garden in Finchmead Lane next weekend. It will be good to do some digging after all the geophys this weekend.