The Leighton Buzzard and District Archaeological and Historical Society (LBDAHS) having been trying to locate the “Holy Well” at Linslade since 2018. The well was very popular in the medieval period, especially in the 13th century. The waters reputedly had healing properties. The well is marked on old maps such as the first edition OS map, but the accuracy of the location is uncertain. The Society have managed to locate a small cottage of 18th or early 19th century date on the banks of the canal which they have partially excavated (Figure 1). In 1915 local historian J. G. Gurney mentioned an old cottage and garden that lay “on the exact site of the Holy Well”, and included a sketch map. This is certainly the cottage which is being excavated.
As well as a variety of post-medieval finds, some of the features have included some sherds of medieval pottery of the right date, and one trench a little to the north of the cottage contained a Romano-British pottery sherd.
From a geophysics point of view the site is quite difficult. The main area of interest is the strip along the edge of the canal which has thick riverside vegetation. The excavation trenches regularly fill with water. The site is, however, on the edge of a steep slope down the canal and so gets drier quite quickly as one moves upslope. What were we hoping to find? One suggestion was that because the well was so popular there might be some form of path or track to the well. If we could detect that, perhaps this would give a clue as to its location.
Pauline, stalwart member of both LBDAHS and CAGG, arranged for us to undertake an exploratory Earth Resistance survey at the site. Due to covid and other commitments this took a bit of time to organise, but finally we managed to earmark a couple of days on site (Fig. 2).
The survey was somewhat jinxed! On the first day, we couldn’t get a reading at all to begin with. I spent quite some time checking the cables and connections and generally making sure all seemed OK to no avail. In desperation I reset the machine to its “factory” defaults and hey presto, all started to work again. Then, as we were working, one of the welds on the frame broke. Luckily we could keep on working by holding the frame on the sides, and the next day a temporary repair was effected by the liberal use of duck tape. On the second morning I found that we had dropped a bracket from the GPS the day before when packing-up. Thankfully, using the GPS to locate where we packed-up and some careful searching around that point, we managed to find it again. Phew.
On the first day, Pauline, Rhian, Kate and I surveyed a line of grid squares parallel to the canal. Partly due to the vegetation we did not get too close to the canal. Also, the waterlogging would result in featureless results and so it simply was not worth the effort (Fig. 3).
On the second day we surveyed a block of grids closer to the current road to see if we could pick-up any buildings in that area. As we usually do, we used the 1+2 method. The RM85’s built-in multiplexer (basically a fancy switching box) means that we collect three readings with each movement of the frame. The first reading has a 1m probe separation and the second two have a 0.5m separation. The 1m separation looks about a meter or so into the ground and the 0.5m separation roughly 0.5–0.7m into the ground. The deeper survey, however, has half the resolution of the shallower survey (1m transect spacing and a 0.5, sample spacing compared to a 0.5m transect spacing and a 0.5m sample spacing).
Figure 4 shows the results of the shallower survey, and Figure 5 the deeper survey.
Looking at Figure 5 first, I would argue that most of what we can see here is geology rather than archaeology. The ground slopes from the bottom of the image to the canal at the top. We can see in the strip of survey at the top of image a band of low resistance readings parallel with the canal. This is almost certainly the transition from the more solid bedrock to river/canal-side deposits and the presence of water. In the area near the road, the high resistance areas near the building are again related to topography rather than archaeology.
The 0.5m probe separation survey in Figure 4 has a few potential features. I have labelled these in Figure 6.
- There is a faint higher resistance line running towards the excavated area on the canalside. This could be a path?
- A small rectangular high resistance feature might be the foundation for something.
- The blue lines indicate two low-resistance linear features. These might be some sort of cut feature (pipeline, robbed wall lines?).
- A high resistance vaguely linear feature.
I wish I could be much more positive with these results and I am the first to admit that none of them are 100% convincing. It might be worth “ground truthing” my tentative interpretations a little more.
Lastly, a thank you to Mike who has subsequently rewelded the frame, and to Jim for making-up some new jump leads ready for the res meter’s next outing.