Kiln — corn-drying in Carrickmines Great

Breen (2012, 120-1) recorded the following details about the excavated corn-drying kiln (F187) from Trench W2 in Area A at Carrickmines Castle (DU026-005001-); 'The corn-drying kiln F187 was very well preserved. It was probably late medieval in date. It was placed directly on top of the old medieval boundary ditch, F186, exactly at the northern edge of the medieval platform. Its position shows that that the boundary ditch was, by then, out of use although not entirely silted up. Slightly to the south of the kiln, on the yellow platform edge itself was a small area of burnt remains (F188). These consisted of what seemed to be a few shallow scrapes in the soil (F253–F256) in which burnt clay, ash and charcoal had been deposited (C422–C424 and C430), but it was extremely difficult to differentiate the deposited material from the natural soil as they were both of the same composition (clay). This area of deposited material may have been associated with the kiln. A soil sample from one of the shallow pits (C423) contained a piece of medieval Dublin Ware pottery. The bowl of the kiln itself was roughly circular, although slightly flattened, with an east–west diameter of almost 4.00m compared to a north–south diameter of 3.00m. It also has an opening, oriented to the southeast, which is almost certainly the result of a missing boulder from the bowl. The flue of the kiln is approximately 2.50m in length and extends from the bowl in a NNE direction. The stones which form the kiln construction are of local granite, in boulders of varying sizes. The stones which form the bowl are very rough indeed, while the stones from the flue have been squared off. Relative to the surrounding ground level the bowl is approximately l.00m deep, while the flue has a depth of approximately 0.60m. It is probable that a wooden platform would have been built on the stones forming the bowl of the kiln and the corn would have been placed upon this. The construction would also have been roofed. Meanwhile a fire would be lit at the end of the flue, driving hot air into the kiln to dry the corn—the remnants of the last fire (C487) were still present in the flue when it was excavated. A possible vent in the flue was suggested by a scattering of burnt contexts just outside the wall of the flue. The bowl of the kiln had been completely filled by several different deposits. Some of the lower fills produced significant quantities of charcoal. The fills of the flue contained large amounts of burnt material, including one layer (C487) which seemed to be a spread of burnt twigs—possibly remnants of the last fire in the kiln. The upper fill of the flue was understandably simply later infill, with no charcoal present. The possible vent contained several different contexts, of which at least three contained some amounts of charcoal. The fills in the bowl began with C362 and C420. Both of these contexts are sandy silts, but C362 is much darker in colour. C362 is on the northern side of the bowl, (and actually is also picked up in the base of the flue), with C420 on the southern side. Above these contexts was C361, a greyish brown gravelly sand with some charcoal inclusions. It is probably the last of the contexts deposited while the corn drying kiln was still in use. It contained some medieval pottery and animal bone. Above this was C334, which appeared to be a small lens of soil with occasional charcoal flecks. The final bowl fill was C324, a brown, gravelly silt which may be deliberate infill, or simply gradual filling up of the abandoned bowl over time. The fills in the flue are slightly more complicated, with a distinct north–south divide. The first deposits would appear to have been in the north of the flue, with C558 being laid down, followed by C557. Both of these contexts are heavily burnt, grey-black layers with large amounts of charcoal. To the south of these contexts, and slightly overlapping them, is C559, a dark layer with many inclusions of burnt clay. C559 appears to have been laid down at the same time as C556, a black, charcoal-filled layer was laid over C557 in the northern part of the flue. Above these contexts are C455, another burnt, brown-black layer with charcoal inclusions (in the northern part of the flue) and C487, the layer of burnt twigs, (which covers C559 in the southern part of the flue). Further to the south, C362 is beside C487 (and therefore probably contemporary with it). All of these contexts are then sealed by C447, the only layer to show no evidence of burning and probably therefore infill after the kiln had gone out of use. Immediately to the north of the flue an enormous modern cut (F267), associated with the 1996 pipeline, has destroyed any further archaeological evidence. The fills outside the flue of the kiln are rather confusing, and represent either minor scattering of flue deposits, packing around the stones of the kiln or possibly leakage or spillage of flue contents caused by a hole in the flue (either deliberate or accidental) which combined with the heating taking place during times of usage might lead to some material being `blown' through the hole. The localised, thin nature of these contexts means that a stratigraphy can only be estimated, and appears to take the form of C666 as the first deposit, followed by C663, C665, C653, C652 and finally C633. However, all of the deposits are of a sandy composition, and they may just be one context, with various differences in colour caused by activity around the flue'. Breen, T. 2012 Report on the Findings of the Archaeological Excavations at Carrickmines, Co. Dublin - Carried out under licences 00E0525, 02E1532 and Ministerial Directions. M50 South-eastern Motorway Scheme 4 volumes. Prepared on behalf of V.J. Keely Ltd. for Dun Laoghaire-Rathdown County Council. See attached site plan showing location of kiln and [photos, section and plan, taken from excavation report under licence No. 00E0525, 02E1532, Breen 2012, Vol. 4. Compiled by: Caimin O'Brien Date of upload: 3 January 2023