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Master Class: Britain’s & Ireland’s Walling Treasures: Redrawing Patterns (part 2)

Written by Sean Adcock – Photos copyright the author unless stated

You can find —  Master Class: Britain’s & Ireland’s Walling Treasures: Redrawing Patterns (PART 1) here.

Another suggestion is that the more vertical the stonework the more problems sheep have if their trying to scale the wall. We could be getting into sheep psychology here, one of my favourite discussions. In the interests of ‘brevity’ my observations suggest sheep frequently run at walls at a slight angle and so if they head from the right direction it might actually help. Maybe Welsh sheep are more intelligent than Southern ones, they are certainly not as fat and probably more agile!

Meanwhile, the man in the Langton Matravers Stone Museum suggested that one theory was the walls lasted better if undermined by rabbits. That is the stones slip into the holes more without really affecting the structure, whereas flat laid stone would be more likely to collapse. Would this actually be the case, how much slippage/accommodation of movement would there be? Then some of the walls are on flat laid footings, and most show no signs of rabbit activity, has it always been thus? An interesting but specious theory? Not all the walls in a Purbeck local field pattern have inclined stonework, so they might have been used as a method of marking a boundary between two properties. Something that needs a bit of research (fraught with problems) before it’s dismissed, although with changes over the years, copycat walling, removals and newer subdivisions, ‘concrete’ conclusions are unlikely.

The one substantive written reference to inclined fencing I have found is not British, it is in Carolyn Murray-Wooley and Karl Raitz’s “Rock Fences of the Bluegrass” referring to “edge fences”- in many parts of America they refer to walls as stone/rock fences. I have only seen one short section in the flesh, and photos of others. By and large these seem to have the stone set more vertically than is the rule on Purbeck. Murray-Wooley describes the building process and says the stones are set at an angle of 30-45 degrees (p.44) however the photos suggest most are angled much closer to the vertical than even 45 degrees.

Kentucky Edge fence, courtesy Mark Jurus

Different areas, similar walls, very different theories. Wetlands and steep slopes do not really apply to the Purbeck variety – although many do run at right angles to the coast where there is more of a slope to the land. I have heard it suggested that those near watercourses resist flooding better. This might make some sense and we’ll deal with this more when I look at harbour walls. However we’d all be in trouble if the Purbeck ones needed to resist rising water. I’m fairly confident we can discount that theory here.

On slopes Murray-Wooley/Raitz argue “for the same reason that coping rocks of a flat-coursed fence lean downhill so that its weight is directed perpendicularly into the hillside.” (p.44). I’m not sure the reasoning is right here and not everyone would agree that coping should be sloped downhill. This said there are sound applied mathematics arguments in favour of sloping downhill however this is very different from the perpendicular argument, which I suspect is specious Ignoring the fact that the photographic evidence suggests the stones generally aren’t perpendicular to the slope, it is unclear why it would be important. Gravity has the same effect on a wall on a slope as on the flat, how the foundations interact with the slope willhave far more implications for the wall than the stonework itself. If the footings are flat then the slope has little relevance. In most respects the wall is independent of it. This said my own thoughts are that the angling introduces lateral forces along the wall as well as vertically towards the base. In a normal flat laid wall there is very little force binding adjacent stones other than some friction and the tying effect of ‘1 on 2’. However the physics all gets a little complicated and not really the stuff of this series

This could also be said of another idea forwarded in “Rock Fences…” relating to the climate. It is suggested that during frost heave the angular nature of the stone and the inclined build means that any frost heave “simply locks the fence tighter” (p.46). Again this is an argument which on the surface might have some credibility, but it is far from clear how its importance, or the physics,‘stack up’ under analysis. As far as we can be sure of anything consistent frost heave has not been, and is not likely to be, a problem in Purbeck (in the near future anyway)! There is an associated idea that “the upright courses provide no place for rain and melted snow to collect and freeze”. Very possibly true although not everyone would agree as to how serious water penetration might be. Ever taken down a wall that is not dusty inside? A similar idea is put forward for the walls in Purbeck, with the angle helping them to drain. However the stone there does not seem as friable as it might be in say the Cotswolds, it’s also not exactly a wet area compared to many walling areas. It does not really seem a credible explanation. Even allowing for stone type, if this is truly a method devised to cope with rainfall wouldn’t you expect it to be a little more widespread?

Alvey mentions the edge fence presence on Irish Ridge an area Irish Catholics settling the area in the 1840s there with the implication that they are Irish in origin, adding “Since they were erected in relatively poor areas, most edge fences in the Bluegrass were probably do it yourself projects, no doubt modelled after similar fences in Britain and Ireland.”(p.42) What walls in Britain and Ireland ? My (limited) Irish contacts suggest that inclined walling (as opposed to ‘vertical’ walling which is quite widespread and herringbone) is relatively rare with sporadic/isolated examples only – although when you look at the size of Purbeck it would not be that difficult to miss a whole area in somewhere the size of Ireland. Avey also mentions that they have no footing simply and are simply built on the ground and mentions a flat cope. Clearly he has not noted the same variety as in “Rock Fences…”. So as to the British connection, does he know something, or is he another one just making it up as he goes along…!!

Back in Purbeck looking at these walls being a local pattern, they of course vary between themselves. We have already noted that the angle of incline can vary, but as can be seen in these two examples. The angling is not necessarily consistent within a wall, often taking on more of a meandering nature than a regimented 30, 45 degrees, or whatever, as can be seen above. It can be difficult to tell if they were built this way or have been subject to numerous repairs, although sometimes it is somewhat more obvious that the wall has been repaired ‘correctly’ as would seem to be the case right. This can be an alarming tendency with highly localised patterns as those working on them might not be capable of replicating the original method or maybe just completely oblivious to them, perhaps even determined to ‘put things right’.

This said inclined stonework does level off occasionally and deliberately. This is the Purbeck method at gateways. It would be technically challenging, to say the least, and arguably structurally unsound to end a wall with sloping stonework. Consequently the end is built flat layed as per a ‘normal’ wall with a metre or two of flat laying before the stonework is gradually tilted to merge with the sloped layers, as can be seen left.

Coping also varies on Purbeck walls, it is often little more than rubble. Rarely do the walls have a neat organised coping as seen earlier in the recently rebuilt wall. It is sometimes slightly more organised and covers can be found on older walls too, as seen on the next page.

As was noted in the original article (doubled) walls tend to be categorised as random or coursed, and with tens of thousands of miles of random wall you would expect to see variations. By and  large these variations remain glossed over, often unrecognised and by and large undefined. As a result ‘random’ tends to be used as catch all. Somewhere down the line I hope Walling Treasures will get to terms with this, as local patterns if not recognised are easily lost. For now we have to content ourselves with (hopefully) just a little eye opening.

There is a lack of readily accessible source material on this aspect of our craft, as with many (most?) areas come to think of it. It is easy to get caught up in ‘Chinese whispers’. In the 1999 re-write of BTCV’s “Dry Stone Walling” I reworked the Galloway/single sections and we ended up with “The ‘butt and hudd’ style mixes single and double walling in fairly random sections along the wall, according to the stone available” (p.144). If no-body else publishes anything I guess there is a danger that that might end up as the widely accepted definition! There is always a risk that articles such as these will just perpetuate, even extend, a myth. In the original 1977 edition of “Dry Stone Walling” Brooks refers to the separate panels within butt and hudd as “sneaks”. A marvellous term which somehow didn’t make the 1999 cut… neither did “snecks” perhaps I spotted a potential link or even a misprint, maybe I just missed it altogether. I am however sorely tempted to resurrect the idea of walling ‘sneaks’ and perhaps create an(other) urban myth.

Anyway I’d be grateful for any snippets of information, even urban myths, on any of the subjects I cover. Help me to make it up as I go along…please!

Thanks to Nick Aitken, Mark Jurus, Richard Tufnell, Andrew Rawson, and everyone else who’s ‘ears’ I bent on this one.

BIBLIOGRAPHY
Alvey. R.G. “Kentucky Bluegrass Country”. University of Mississippi Press. 1992
Murray-Wooley.C. & Raitz.K. “Rock Fences of the Blue Grass”.University Press of Kentucky. 1992
Rainsford-Hannay.F. “Dry Stone Walling”. 3rd reprint. South West Scotland Branch of the DSWA. 1999

The content below was copied with the generous permission of the author Sean Adcock.  This Master Class article originally appeared in the No.29,  Summer 2013 of STONECHAT, produced by the North Wales Branch of the Dry Stone Walling Association of Great Brittan.  

This entire issue of Stonechat, and many more, are available at http://www.dswales.org.uk/Stonechat.html  Thank you to Sean for allowing us to provide this content, and please donate to The North Wales Branch.

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