Rowberrow Barrows on Mendip, Somerset

8/14/2019 Rowberrow Barrows on Mendip, Somerset

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Rowberrow Barrowson Mendip, Somerset

Rowberrow barrow, from Plummers Lane 10 June 2006

Earthwork & Geophysical Surveys

CHERT 2004-6


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Rowberrow Barrowsin Priddy on Mendip, Somerset

Earthwork & Geophysical Surveys 2004-6CHarterhouse Environs Research Team

Summary

Earthwork and resistivity surveys were conducted on and around a group of three roundbarrows on Mendip. The earthwork survey revealed a circular ditch around the eastern barrow,which the resistivity survey confirmed to some extent. The resistivity survey also revealed acomparable ditch around the western barrow. It also suggested several phases of linear ditches,some apparently underlying the barrow group. Other areas of ground, probably disturbed andlater flattened by ploughing, may represent post-Medieval mining activity.

IntroductionA small Bronze Age barrow cemetery lies at the high point of 275m OD beside theB3135 Plummers Lane, Priddy. Four bowl barrows are Scheduled Monuments (SM13853-6 and also recorded on the Somerset HER 24003-6) and one barrow (SM 13855)has long been called Rowberrow. (Cover photograph & Fig.6). The three easternmost

barrows that were surveyed lie in pasture fields, one with considerable scrub of gorseand hawthorn (cleared by December 2006). The surveys were undertaken by volunteermembers of the Charterhouse Environs Research Team (CHERT) in 2004-6 and permis-sion was granted by English Heritage to undertake the geophysical survey in February2006. The fourth barrow to the west (SM 13853, HER 24003), much damaged byploughing in an arable field, was not included in the survey.

Fig.1 Location map of Rowberrow barrows.Background map Crown copyright/database right 2004. An Ordnance Survey/EDINA supplied service. 1


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AimsThere were two main aims of the work; the first to produce accurate measured earth-work surveys and the second to investigate any buried features around and betweenthe three easternmost barrows.

LocationRowberrow barrow itself (SM 13855) now in the parish of Priddy, formerly lay on the

boundary between the parishes of Rodney Stoke and East Harptree at NGR ST 5225

5232. As a boundary marker the barrow is recorded in the Perambulation of the Libertyor Royalty of East Harptree in 1768 (Grinsell 1971). The name of the barrow has also

been spelled Rowbarrow, Roburrow, Rough Barrow and none should be confused withthe former mining parish of Rowberrow 9 km to the NW at NGR ST 449586. Thespelling used in this report follows that of the Somerset HER.

Fig.2. Map of barrow groups visible from Rowberrow.Background map taken from Crown copyright Ordnance Survey Explorer 141 1:25,000 scale. 2


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From Rowberrow a number of other important Bronze Age barrow groups are clearlyvisible on the horizon, particularly those on Black Down (6.2 km) and on Pen Hillabove Wells (5.5 km). Nine Barrows and the Ashen Barrow group at Priddy (1.7 km),two linear cemeteries on Bristol Plain (1.5 km) and Westbury Beacon (2.8 km) on thesouth west scarp edge of Mendip are also clearly visible. Fig.2. The Somerset HERrecords 101 round barrows within a 3 km radius of Rowberrow barrow, but trees,hedges and farm buildings now make it difficult to check in the field how many wouldhave been visible when they were constructed.

Another aspect of the signifance of this high spot is that Day & Masters map of 1782shows five tracks meeting at this point. Four tracks are shown crossing the unenclosedpasture of Mendip by dotted lines, while the track from the east approaches the barrowgroup between the medieval or post-medieval enclosures of Chancellors Farm on thenorth and the outer enclosures of Priddy to the south. On the map this part of the trackis drawn with continuous lines. The track running northwards is the one passing

between Rowberrow barrow and the barrow to the east which heads to ChancellorsFarm before continuing to Haydon Grange [Hydon] Farm.

Fig.3. Day & Masters 1782 map of Mendip with location of Rowberrow barrow added.

GeologyThe underlying solid geology is Carboniferous Black Rock Limestone and the soilsaround the barrows have been mapped as peaty gleyed podzols of the Priddy Series.The drainage of these soils has been described as Poor-Very Poor and Findlay (1965, 42)continues that they are characteristic of thick silty drift deposits overlying hard lime-stone. He also comments that there is strong archaeological evidence to support theview that some of these soils result from the spread of heath vegetation, followingclearance of former deciduous woodland by early man. (Dimbleby 1952, 1954 & 1955).He suggests that this heathland regeneration took place in the period of the 4th-13thcenturies when the Mendip Plateau was almost abandoned.

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Findlay also comments that, since the mapping of the Priddy Series in 1946, some ofthe soils have been greatly modified by ploughing (1965, 54). He notes that many fieldsin this neighbourhood were not improved until very recently owing to the presence ofswallets, isolated lead workings and numerous boulders of silicified Liassic rock. Thepost-War Marginal Land Scheme stimulated ploughing, liming and reseeding in thearea. The 1946 aerial photograph of the area taken before the Scheme was introducedshows much evidence of lead mining rakes less than 1km to the north and numeroustrial pits closer to the barrows. Fig.5.

Permission to undertake the geophysical surveys was obtained from English Heritage(Amor) and the owners and tenants Mark Atkinson, the Ministry of Defence and theSomerset Wildlife Trust.

Previous workPrevious observations and measurements are summarised in the Somerset HistoricEnvironment Records (HER 24004-6). Except for the grid reference, height and diame-ter of the barrows little is recorded. It is noted that SM 13854 was trenched by B C Birdin c.1900 without result and that a hollow on the south west side of the barrow may be

the result of further excavation or stone quarrying for road metal. At SM 13855 the fieldwall and parish boundary cross the barrow and it appeared to have been disturbed onthe east. Immediately to the east are two irregular shaped mounds which may be con-nected but are not likely to be mine workings. Finally for SM 13856 a ditch is noted 6ftwide and 1ft deep best visible on the south, east and west sides. Also Mining hasencroached on the north east but it is possible that there is a causeway here. The

badger sett, first noted in 2000, was still active at the time of the geophysical survey.

In 1992, when the Scheduling was affirmed with new national numbers, all three bar-rows were ascribed buried ring ditches, without investigation (EH 1992).

Earthwork survey of barrow SM 13854 (Fig.9. Drawing No. 465/1).This barrow lies in a small paddock used for grazing horses and is clear of any scrub. Itwas surveyed in the summer and autumn of 2004 at 1/100. B C Birds trench is stillclearly visible, as is the quarry scoop and waste spillage on the south and south east.The ground survey also revealed a second scoop on the east side, perhaps anotherarchaeological attempt to reach any internal burial. English Heritage claim Althoughno longer visible at ground level a ditch, from which the material was quarried duringthe construction of the monument, surrounds the barrow mound. This has becomeinfilled over the years but survives as a buried feature c.3m wide (EH 1992). No ditch

around the barrow was detected as a surface feature in this survey.

Fig.4. View of barrow SM 13854 looking west.


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Fig.5. 1946 aerial photograph of the area around Chancellors Farm & Rowberrowbarrow group.

Earthwork survey of Rowberrow barrow SM 13855

(Figs.10 &11 Drawings Nos. 466/1 & 466/2).

Fig.6. View of Rowberrow barrow SM 13855 looking south west.


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Rowberrow barrow and its immediate environs were surveyed in March 2004 at 1/100.The survey records the truncation of the barrow on its south and south-western sides.The former caused by the re-alignment of Plummers Lane and the latter by the con-struction of a farm access track running northwards. Aerial photographs confirm that

both events took place after 1946. Fig.5.

English Heritage claim Although no longer visible at ground level a ditch, from whichthe material was quarried during the construction of the monument, surrounds the

barrow mound. This has become in-filled over the years but survives as a buried fea-ture c.3m wide. (EH 1992). No surrounding barrow ditch was recorded by CHERT inthis earthwork survey. However the complex of barely discernable earthworks immedi-ately to the east of the barrow were carefully recorded. The long very low bank to theeast was covered in ruts from vehicles using the field gate to their south and headingnorth east to Chancellors Farm.

Earthwork survey of barrow SM 13856 (Figs. 12 & 13. Drawing Nos. 467/1 & 467/2)This barrow was surveyed in February 2004 also at a scale of 1/100. The surroundingring ditch was very evident on most sides. A large depression in the top of the barrow,

not previously recorded, looks very much like antiquarian activity, although it is nowmuch disturbed by badgers. A damp shallow ditch runs north west from the ring ditchand looks like a natural spring feature. Similar linear ditches run from the ring ditch onthe east and south east, although these appear much drier.

Fig.7. View of barrow SM 13856 looking south west, with Rowberrow barrow in thebackground.

Ground levels & barrow heightsThe four barrows in this linear cemetery group are orientated approximately ENE WSW. The distance between Rowberrow barrow and each of its neighbours is 70m; thefourth barrow to the west lies at three times 70m or 210m and there is no earthwork oraerial photographic evidence of any further barrows between. Whether this regularityhas any significance or not is not known. Relative ground heights and barrow summitheights were established by theodolite and the results are shown below in Fig.8.

The ground continues to slope gently downwards to the west leaving the fourthbarrow much lower than the other three. All three surveyed barrows are very similar inheight above ground level ranging from 1.50 1.65 m. Rather surprisingly Rowberrow

barrow itself is neither the highest nor on the highest ground, so the reason why it isnamed and was used as the boundary marker is not clear. All have been damaged byantiquarian exploration, badgers, road building and/or wall building so that present-day heights may be misleading. 6


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Fig.8. Comparisons of relative ground levels and barrow heights.

Resistivity surveysThe resistivity surveys were carried out one morning per week from March to June2006. A grid of 20m squares was established around each barrow. Each of these squareswas then surveyed using a TR/CIA resistance meter. The Twin Electrode configurationwas employed with a probe spacing of 0.5m. Readings were recorded at 1.0m intervalsalong traverses spaced 1.0m apart. The data was downloaded using TR Systems soft-ware and a variety of algorithms have been applied to the raw data to aid visual recog-

nition and interpretation using Archeosurveyor software. Fig.14 shows all three areasrecorded using data resulting from a High Gaussian pass. High resistance areas aredark in tone, while low resistance areas are light.

Interpretation of resistivity dataInterpretation of the results is shown in Fig.15. The western barrow SM 13854 is clearlyrevealed by the dark circular area representing relatively dry soil and/or stone. Anumber of highly contrasting light or wetter areas are clear within it and aligned NNE.These appear to relate quite closely to the surface excavations recorded in the earth-work survey (Fig.9). There is some evidence of a circular lighter or damper feature

around the barrow presumably the buried surrounding ditch predicted by EnglishHeritage. However a clearer feature is a drier linear feature running WSW from pointA around the barrow and perhaps then running NE to point B. This does not appear tocontinue in the plots to the east. To the north and south of the barrow are areas wherethe resistivity data appears to suggest disturbed ground.

The dry structure of central Rowberrow barrow SM 13855 shows in the plot to the westof the N-S boundary wall and immediately to the west of the barrow the crudely met-alled track running S-N is revealed in the parallel wetter lines running C to D.However to the east of the wall the dry barrow is not picked up clearly by the resistivi-ty, nor are the other earthworks shown in Fig.11. Instead there appears to be an under-lying rectangular grid of damp lines, probably resulting from underlying geology.

Further east the broad lighter bands running N-S from E to F are following the route ofa current field track to Chancellors Farm. 7


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The third barrow SM 13856 is reasonably clearly defined by the darker drier area, butits internal structure is far more complex than its surface topography would suggest.Perhaps this reflects the internal damage caused by the badger sett that is undergroundwithin the barrow. The surrounding ditch, evident in the earthwork survey, is not clearfrom the resistivity data. The most prominent feature here is the sharp dark/light

boundary running NNE from the barrow to point G.

Discussion

The resistivity results suggest a complex underlying archaeology and geology. Whilethe three barrows are evident their predicted surrounding ditches are not so clear.Instead more linear features are revealed and a small-scale rectangular grid may repre-sent ditches or, more likely, the underlying geology of cracked limstone rocks(pers.comm. Albert Thompson).

The eastern boundary of the Priddy podzols mapped in 1946 appears to follow the lineof the stone wall running northwards from the main road and towards ChancellorsFarm. The field to the east is mapped with the free-draining brown earth of the MendipComplex. Perhaps that area had been improved in the late medieval and/or post-

medieval periods. The resistivity plot of the field surrounding barrow SM 13856 showsa damp area alongside the wall with a relatively straight boundary running roughlyparallel to it with much better drained ground to the west. It may be that the resistivitydata is revealing an area of post-War improvement by ploughing, liming & reseeding,perhaps stimulated by the Marginal Land Scheme, as to the north and outside the areaof survey the 1946 aerial photograph shows that the field is pock-marked with quarry-ing or mining holes, some of which are no longer visible on the ground.

An alternative interpretation may be that the dark, dry line running north from the bar-row may represent the remains of the 18th century wall, that was the precursor of the

present wall 10-20m. to the east (pers.comm. Albert Thompson).

Recommendations1. Repeat the resistivity survey of the ground to the east of SM 13855 at the higherresolution of 0.5m intervals.2. Research agricultural activity in the area since 1946.

Bibiography & sourcesAmor, G 15 February 2006 correspondence with English HeritageBritish Geological Survey 1984 England and Wales Sheet 280: Solid and Drift GeologyDimbleby, G W The historical status of moorland in North-east Yorkshire NewPhytol. 51, 349-54Dimbleby G W The origin of heathland podzols and their conversion by afforestationRep. 8th int. Bot. Congr. 13, 74-80Dimbleby G W The ecological study of buried soils Advmt Sci., Lond. 12, 11-16EH 1992 Correspondence English Heritage to SCED 23.09.1992Findlay, D C 1965 The Soils of the Mendip District of Somerset Agricultural ResearchCouncilGrinsell, L V 1971 Somerset Barrows, part 2 Proceedings of the SomersetArchaeological & Natural History Society 115, 67Somerset Historic Environment Record www.somerset.gov.uk


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List of illustrations

Cover. Rowberrow barrow, from A3135 Plummers LaneFig.1. Location map of Rowberrow barrowsFig.2. Map of barrow groups visible from RowberrowFig.3. Day & Masters map of Mendip with location of Rowberrow barrow.Fig.4. View of barrow SM 13854 looking westFig.5. 1946 aerial photograph of the area 3G-TUD-UK-15-24-part1-5019

Fig.6. View of Rowberrow barrow SM 13855 looking south westFig.7. View of barrow SM 13856 looking south westFig.8. Comparisons of relative ground & barrow heightsFig.9. Dwg.No 465/1 of barrow SM13854Fig.10. Dwg.No 466/1 of Rowberrow SM 13855Fig.11. Dwg.No 466/2 of Rowberrow SM 13855Fig.12. Dwg.No 467/1 of barrow SM 13856Fig.13. Dwg.No 467/2 of barrow SM 13856Fig.14. High Gaussian pass over raw data from resistivity surveyFig.15. Interpretation of the resistivity data

Earthwork surveys by: Shirley Everden, Jenny Greenslade, Mike House, BobSmisson & Jane Snelling

Date of earthwork surveys: February October 2004

Resistivity surveys by: Percy Lambert, Barry Lane, Rita Miller, FrancesNeale, Jill Polak, Byron WinterDate of resistivity surveys: 21 March 6 June 2006

Resistivity data processing: Albert Thompson

Theodolite survey of heights: Jack Foord

Report on behalf of CHERT by: Barry Lane2 Glencott, The Hollow, Westbury-sub-Mendip,Wells BA5 1HH

[email protected]

Date of report: 1 February 2007


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Fig.9. Drawing No.465/1 of barrow SM 13854 10


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Fig.10. Drawing No. 466/1 of Rowberrow barrow SM 13855 11


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Fig. 11. Drawing No. 466/2 of Rowberrow barrow SM 13855 12


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Fig.12. Drawing No. 467/1 of barrow SM 13856 13


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Fig.13. Drawing No. 467/2 of barrow SM 13856 14


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Fi .14. Hi h Gaussian ass over raw data from resistivit surve . 15


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Fig.15. Interpretation of resistivity data. 16

Rowberrow Barrows on Mendip, Somerset

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