2002:1179 - INCHAGREENOGE (BGE 3/45/1), Limerick

This site was examined as part of Bord Gáis Éireann’s Pipeline to the West. It was on the western edge of a low-lying area of bog, at the base of a steep hill. To the east the area was bounded by a stream, and several springs were encountered during excavation.

The site was characterised by two fulachta fiadh with wood-lined troughs, a spring with a deposit of a human skull, several layers of peat containing numerous wooden artefacts, and a post-medieval stone trackway. The area of investigation measured 44m by 19m (836m2). Owing to water-management problems and the time pressures of the pipeline construction programme, the entire area was not excavated to the top of the natural geological deposits; however, it is felt that most of the archaeological features and artefacts were found.

A small amount of machine damage had been caused to the site before excavation. This disturbance made it impossible to relate directly several elements within the site.

The site is described in several phases, ranging from prehistoric to post-medieval; however, as direct physical relationships were not seen between all of the elements of the site, these are generalised. The nature of the peat growth meant that it was not possible to determine a definite horizontal stratigraphy with which to relate different parts of the site; for example, it is not known whether the two fulachta fiadh were contemporaneous or one preceded the other in the sequence of peat development.

A thin layer of mid-blue/grey silty clay was recorded lying directly on the surface of the natural sandy clay below the peat at the eastern end of the site, adjacent to the stream. This appeared to be natural weathering of the clay and may have occurred while the area lay below water. The roots of several trees were observed growing in this layer. Three deposits of burnt and unburnt stones and pieces of wood lay above the silty clay layer, below the lowest peat layer, at the eastern end of the site. A spread of large stones below the peat at the western end of the site may also be of this phase.

A layer of peat extended across most of the site. This peat was thicker at the east, toward the stream, and became thinner as the underlying ground surface rose out of the bog to the west. It was difficult to relate the peat at each end of the site and to differentiate between this layer and the overlying peat, as the break was determined by archaeological stratigraphic factors rather than observed differences. The peat included a large amount of preserved wood, including branches and twigs, and seeds/nuts. Assemblages of worked wood and animal bones were recovered. At the western end of the site a soil layer spread uphill from the edge of the peat onto the dry land and may be contemporaneous.

Part of a possible wooden trackway recorded within the peat was constructed from a few large pieces of timber and smaller branches. Three worked stakes were driven in nearby to support the rough structure. Preserved grass, found below the timbers, may have been deliberately laid as part of the construction. A small assemblage of animal bone and the only sherd of prehistoric pottery from the site were recovered from this possible trackway.

The next phase was represented by two fulachta fiadh. The eastern one was c. 9.5m in diameter and a maximum of 0.15m thick; the western one measured 16.8m by at least 19.2m and was at most 0.26m thick. Both spreads overlay subrectangular troughs lined with timber planks and stakes. At the southern edge of the larger burnt stone spread a natural spring bubbled up through a hole that was at least 0.6m deep and was surrounded by large, natural, limestone pieces.

At the western end of the site a layer of stones was cut by a small pit filled with burnt stone material. The relationship between these western features and the fulachta fiadh is unclear.

In the edge of the spring, in a thin deposit of peat above the burnt stone spread, was a human skull, apparently deliberately deposited. The skull was overlain by a layer of large unburnt stones, which capped the spring and gave the impression of a stone platform.

A further layer of peat covered the entire site, overlying both fulachta fiadh, although in places where no burnt stone separated the deposits it was not possible to distinguish this from the lower peat layers. The peat was rich in wood, with plentiful preserved branches, twigs and seeds, particularly hazelnuts. As with the upper peat, large numbers of worked wood pieces and animal bones were recovered. After the deposition of this peat layer, the site appears to have been flooded for a time, as 0.15m of alluvium overlay the entire area.

A layer of large, unburnt limestone pieces at the northern edge of the site appeared to form a post-medieval stone trackway crossing part of the bog and sitting on the alluvium. The trackway measured 18m by 3m and was 0.2m thick, generally comprising a single course of randomly placed stones. The trackway began at the dry, western edge at the base of the incline and extended toward the stream.

Finally, three stone-lined drains extended across the site. Overlying all of the features were two thin layers of relatively recent peat. Several large pieces of bottle glass, probably from an 18th-century onion flask, were recovered above the stone trackway.

A large number of finds were recovered, mostly animal bone or wood. Also collected were a few flint flakes and scrapers, a single sherd of decorated prehistoric pottery, several sherds of post-medieval pottery, fragments of clay tobacco pipe, fragments of post-medieval glass, a handle fashioned from antler, and the human skull found in the spring. The animal bone assemblage is considerable and, as it is most likely prehistoric, of great significance. Also preserved in the peat were several unusual wooden artefacts, including a mallet, pegs and a small, scalloped item. These, and the trough timbers, will be identified to species, and the toolmarks will be examined to establish the woodworking techniques used.

In addition to bulk soil samples, a peat column was taken for pollen analysis, and a block sample of the better-preserved trough, including the timbers, fills and surrounding peat, was taken. It is hoped that microscopic examination of the timbers will reveal hairs or fibres trapped in the grain of the wood and that chemical analysis of the timbers and trough fills may show lipid or other residue.

It is anticipated that several radiocarbon determinations will be obtained, from the human skull, the fulachta fiadh troughs, the wooden artefacts and elements of the peat itself, such as hazelnuts, which were preserved in large numbers.

Excavations at this site have provided a vast amount of information. Two fulachta fiadh, the layers of peat growth with wooden artefacts and animal bone, the apparently ritual deposit of a human skull in a spring, and the post-medieval trackway and drains testify to a long period of use of the site. At this stage the time-span covered by the prehistoric activity is not known. The two fulacht fiadh may have been contemporaneous and swiftly followed by the skull deposit as the peat overtook the mounds. Alternatively, the site may have been revisited over a period of several hundred years while the peat growth continued slowly. Artefactual and ecofactual analysis and absolute dating should allow the resolution of these issues.

Of particular interest is the as yet undated human skull placed in a natural spring. It is assumed that, rather than being a regular funerary practice, the deposition had a greater significance, related to the location as well as the human remains. Numerous examples of deliberate deposits of human remains in watery contexts are known across Europe, with a small number recorded in Ireland. These deposits, often found in association with objects such as stone axes or metalwork, range in date from the Neolithic to the Iron Age. The association of the skull from Inchagreenoge with a fulacht fiadh suggests that it may prove to be Bronze Age or Iron Age. Five possibly comparable Late Bronze Age skulls deposited in wetland contexts in Ireland are discussed by Cooney and Grogan (1994, 146–7). Although no metalwork of this date was recovered from the site, there may have been a ritual or votive element to the deposition of the wooden artefacts and the animal bone assemblage.

The artefactual assemblage is also of great interest and potential. The excellent preservation conditions have provided an insight into a category of items that does not usually survive on archaeological sites, those constructed of wood. The animal bone assemblage is also particularly significant, and the human skull is worthy of detailed examination.

This site is clearly of exceptional interest and importance. Further analysis and absolute dating will allow a full interpretation of the significance of the evidence.

Reference
Cooney, G. and Grogan, E. 1994 Irish prehistory: a social perspective. Dublin.

2 Killiney View, Albert Road Lower, Glenageary, Co. Dublin