1998:222 - 'THE BREHON'S CHAIR', Taylor's Grange, Dublin

An extensive programme of archaeological monitoring and excavation was carried out between 15 April and 19 June 1998 in advance of a housing development adjacent to the south and east of the Brehon's Chair portal tomb, Taylorsgrange, Rathfarnham.

Four seasons of excavation by Valerie Keeley to the north of the tomb had revealed a wide scatter of features accompanied by fine and coarse pottery and a wide range of lithic artefacts dating to the Neolithic to the Early Bronze Age (JIA V, 1989–90; 74, Excavations 1985, 23–4; Excavations 1986, 18; Excavations 1987, 14–15). In 1996 work by Tim Coughlan involving two archaeological assessments and a geophysical survey in the area of the proposed development revealed a number of features of archaeological potential (Excavations 1996, 39).

Despite the fact that much of the archaeological material discovered in the course of the excavation was fragmentary and highly truncated by later agricultural activity, the site yielded evidence of Neolithic, Beaker, Early Bronze Age, Iron Age and Early Christian activity in the form of hearths, post-holes and pits.

After the removal of topsoil the site was divided into three areas, A, B and C.

Area A lay 35m east of the Brehon's Chair. It was highly truncated by post-medieval agricultural activity, which removed virtually all horizontal stratigraphy, leaving only an incoherent series of negative features.

It showed evidence of two phases of use, although these were not clearly distinguishable between all the features recorded. It was cut by a number of stake-holes most of which had no coherent pattern, although several may have represented the truncated remains of small fences. There was also evidence of three hearths, F11, F26 and F69, across the area, all of which survived as small areas of fire-reddened clay over natural. F26 was surrounded by a series of three double stake-holes, which probably functioned as some form of hearth furniture, possibly a tripod. A small burnt pit 5m to the north of F26 produced a calibrated date of 3620–3356 BC. There was an almost complete absence of diagnostic artefacts from Area A, a burnt hollow scraper being a notable exception.

Those features that can be reasonably linked to Phase 2 activity consisted of several spreads of charcoal-flecked clay, which sealed earlier stake-holes, and a linear spread of stone, F40, some 5.8m long, which had been badly disturbed by later activity. The function of F40 was unclear. Two highly weathered Beaker sherds were found adjacent to it; it was not apparent whether this pottery was in situ or redeposited as a result of later disturbance.

Although no clear pattern could be placed on the features within Area A, it appears that they represented some form of small-scale or marginal activity adjacent to the monument, perhaps the tail-end of the more substantial activity discovered by V.J Keeley to the north.

Area B, 14m south of Area A, contained the only evidence of in situ and coherent archaeological stratigraphy across the site.

The earliest phase consisted of a Beaker hearth-pit, F231, which was surrounded on one side by two concentric lines of stake-holes forming windbreaks. Roughly 1.2m to the north-west of the hearth lay a small burnt pit that contained flecks of cremated animal bone. This was surrounded by an almost continuous ring of small stake-holes, which again appeared to act as some form of windbreak around the pit.

To the north of the hearth was evidence of three small, east-west-orientated fences running across Area B. The maximum surviving length of any of them was 2m. Their proximity to each other suggested that they were not contemporary. It was likely that they acted as windbreaks, sheltering the area around the hearth.

Phase 2, Level 1, consisted of a layer of dark brown/purple, sod-like, humic clay, F101, which probably represented the remains of an old ground surface. This sealed the Beaker features and contained a number of decorated vase urn fragments, several of which had carbonised material on their inner surface. Although no cut features or structural elements were discovered, six pieces of baked clay, interpreted as daub, suggest the possibility of adjacent features. The carbonised material on the interior of the vase urn also suggests domestic activity.

A layer of compact, brown clay, F102, which acted as the working surface for Phase 2, Level 2, sealed F101. The central feature of this level was a rough stone surface, F124. The surface was orientated north-west/south-east, an axis of orientation that ran directly through the Brehon's Chair to the north-west. The entrance to the south-eastern end of the surface was formed by two large boulders, which were tightly hugged by the cobbles.

At the north-western end of F124 lay a small burnt pit containing fragments of cremated animal bone. Much of F102 was sealed by a compact, burnt, black clay, which appeared to have accumulated as a result of the activity associated with the use of the pit.

Phase 3 dated to the early part of the Early Christian period and was represented by a series of three successive large burnt pits, all in a small area measuring 3m x 1.5m. These pits lay 3m to the west of the Beaker hearth and had been heavily truncated by a trial-trench dating to 1996.

Black, charcoal-rich clays, some of which contained charred cereal remains, filled what remained of the pits. The bases of the pits, where they survived, had been reddened through intensive burning. It has been suggested that these pits may have functioned as areas where grain was dried out/ processed before consumption; the validity of this interpretation should become clearer following post-excavation analysis.

A date of AD 540–647 was obtained from the fill of F93, the latest in the series of pits. The fact that the two earlier pits were identical in form, and located directly below F93, suggested that they were broadly contemporary.

Area C was heavily disturbed by post-medieval activity, and only isolated stake-holes survived. Despite this, 52 sherds of Beaker pottery, representing at least seven vessels, were retrieved from the ploughsoil covering the area.

Monitoring of soil-stripping for house foundations and for the site access road also revealed a number archaeological features, including two possible hearths, scatters of stake-holes, several large postholes and three large burnt pits.

Two of the burnt pits, F182 and F236, lay within 1.2m of each other and 15m south of Area B. They were similar in form and size to the Phase 3 pits in Area B, and their bases were also fire-reddened. They contained no evidence of cereal remains and were somewhat earlier, with F182 yielding a date of 160 BC–AD 58.

F143 lay 15m south-west of F182 and F236, was shallower and contained fragments of cremated animal bone. F143 was dated to between AD 238 and AD 392.

The function of these pits is uncertain. F182 and F236 may have had a similar function to the pits in Area B and may represent a form of cereal processing that was carried out in the area over a period of 500–600 years. F143, on the other hand, may have functioned as a cooking-/roasting-pit.

Phasing and interpretation of most of the archaeological features excavated was extremely difficult owing to the high level of later agricultural disturbance and to the fact that within the confines of the development many of the features occurred in relative isolation. Despite this, we can speculate that the area was occupied through the prehistoric period up to at least the Early Christian period.

The Neolithic evidence discovered suggests that the main settlement was concentrated to the north of the monument, with more peripheral activity occurring to the east in Area A. The available evidence suggests that the Beaker occupation was centred on the higher ground to the south of the monument. Although no coherent structural elements were found associated with the Beaker hearth F231, it is likely that it was domestic in function. Beaker house sites are rare in the Irish record, with many 'domestic' sites being represented by pottery scatters and hearths. Despite the truncated and fragmentary nature of the surviving evidence, the spread of Beaker pottery across Areas A, B, C and in some of the areas monitored to the south of these suggests widespread Beaker activity across the site.

The Early Bronze Age material again appears to be domestic in nature. Sherds of vase urn have been known to occur in habitation contexts, for example in Dalkey Island. This level appears to have been deliberately sealed by the clay F102. The orientation of the stone surface F124 with the monument may suggest a possible ritual function.

Wood identification of the charcoal filling the Early Christian pits indicates a managed landscape, with hedgerow species being identified along with cereals, straw and weeds that grow alongside cultivated species. Although this evidence implies that the area was inhabited, no such features were identified.

Thus despite the fragmentary nature of the archaeological evidence it is apparent that the Brehon's Chair remained a landmark for the inhabitants of the area throughout the prehistoric and early historic period.

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