Kiln — corn-drying in Portmarnock

A residential development has been completed where the monument stood. Nothing remains. Entirely removed by excavation under licence 16E0613 in advance of development. The results of this excavation were summarised by Gill McLoughlin as follows; 'The excavation comprised the remains of a large sub‐surface ditched enclosure (DU015‐014001-) adjacent to the upstanding Portmarnock mound (DU015‐014----), east of the railway line at Portmarnock and south of Station Road. The archaeological excavation took place over fourteen weeks from the 9th January 2017 with a team of ten archaeologists and six general operatives. Excavation at the site followed previous archaeological monitoring and excavation in relation to Phase 1A of a permitted development immediately to the west of the enclosure site (Planning Ref. F13A/0248). The excavation that is the subject of this report is referred to as Phase 1B (Area 3). During the phase 1A archaeological investigations targeted testing was carried out on the phase 1B enclosure to confirm its existence and its nature and extent. The enclosure was slightly elliptical or sub‐circular in plan and measured a maximum external diameter of 77m east‐west x 70m north‐south (68m east‐west x 60m north‐south internal diameter), with an entrance to the east. Cereal drying (kilns) and metalworking activity were evident within the enclosure and a single adult male burial was also located within the interior. Further early medieval imported pottery (E ware) was recovered from other features within the enclosure. Area 3a lay within a southwest‐northeast pipeline trench / haul route from the phase 1A housing development to temporary attenuation pond no.1. Excavation of this area took place over three days from 18th‐20th May 2016 with three archaeologists. This trench, although it was not apparent at the time, cut through a ditched enclosure (SMR DU015‐014001-) and two features (C13 and C15) identified during monitoring of topsoil stripping were excavated and preserved by record. The features represent a cereal drying kiln and a linear feature of uncertain function, possibly serving as a windbreak to the kiln. At the time, it was thought that they were isolated features but subsequent targeted archaeological testing showed them to be internal features within a large ditched enclosure (DU015‐014001-). The pipeline was laid at a depth of approximately 5m. The exposed extent of the kiln measured 2.9m north‐south x 1.05m east‐west x 0.3m deep. The bowl was located at the northern end and the stoke hole to the south. The cut was clear and regular at the bowl end and had steep sides and a gently rounded base. Kiln C15 continued beyond the pipeline route to the south and was fully excavated during the phase 1B works (16E0613) and is further discussed in section 4.3.9 where it is referred to as C261. In the bowl, there were three fills (C20, C19 and C14). The basal fill in the bowl was a grey brown silty clay with moderate inclusions of animal bone, shell and charcoal (C20) and at the other end the basal fill was dark black‐grey silty clay 0.15m deep with abundant charcoal (C24). Overlying both C20 and C24 was a loose deposit of yellow‐grey gritty sandy silt with moderate charcoal and occasional bone (C19). The upper fill was dark brown‐black silty clay (C14) with frequent animal bone, occasional burnt bone, slag and seashell. This deposit was only present at the northern end of the kiln. Cut C15 equates to C261 from the phase 1B excavation and fills C19 and C24 equate to C291 and C292 respectively. Kiln C261 - C261 was a cereal drying kiln located in the southern area of the site and was aligned north‐south. The northern part of this feature was excavated during the Phase 1A works in May 2016, and the remainder was excavated during Phase 1B in April 2017. In total the kiln measured 3.8m long by 1m wide and 0.3m deep. The portion excavated during phase 1B was the southern end of the kiln and measured 1.1m north‐south by 1m east‐west and was 0.17m deep. The break of slope at the surface was sharp with steep almost vertical sides and a sharp break of slope to a flat, slightly concave base. Two fills were contained in the kiln and the lower fill C292 was a moderately compact layer of charcoal rich black silty clay with inclusions of cereal grain. This layer measured 1.1m by 1m and was 0.17m thick. Four fragments of dense slag (105g) (Rondelez, Appendix 5.7) and a sherd of unidentified early medieval imported pottery (16E0613:222) (Doyle, Appendix 5.1) were recovered from this layer. This black charcoal layer was partly sealed by C291, a thin band of moderately compact yellowgrey redeposited silty clay subsoil measuring 1m east‐west by 0.55m north‐south and 0.04m deep. This layer contained inclusions of small stones and occasional charcoal flecks. A sample of charred wheat (Hordeum sp., 0.1g) (Lyons, Appendix 5.9) from basal fill C292 returned a date range of 1107+/‐28 BP (UBA 36096), which was calibrated to AD 883‐1011 (2 sigma), indicating a date towards the end of the early medieval period for this phase of kilning activity (QUB, Appendix 5.14). A sample of fill C292 selected for environmental analysis contained both charred plant remains and charcoal. The charred plant remains were dominated by wheat, followed by barley with smaller quantities of oat and wild taxa and their presence indicates that the kiln was not cleaned out after it was last used and may have been abandoned after a fire. The composition of crops identified indicate a different harvesting phase or season from kiln C119 and this is supported by the dating evidence which places kiln C119 in the 5th/6th Century and kiln C261 in the 10th Century. Recent research has indicated that barley was more dominant in the earlier medieval period, pre c.700 and after this it declines on many sites and this is reflected in the plant species analysis and dating evidence for kilns C119 and C261. The wood species represented in the charcoal assemblage are very similar to those from kiln C119, being dominated by hazel, followed by pomaceous woods with smaller quantities of ash, willow and blackthorn (Lyons, Appendix 5.9). Of the recovered animal bone from the kiln, three bones were countable and none were burnt suggesting they were dumped in the kiln after it went out of use (Murray, Appendix 5.10). (McLoughlin 2019a 22-3; McLoughlin 2019b, 8-9; 37-8). See attached photographs and plan of site courtesy of and © Gill McLoughlin of Courtney Deery Heritage Consultancy Ltd. McLoughlin, G. 2019a Final Archaeological Excavation Report, Station Road, Portmarnock, 16E0101. Unpublished archaeological report submitted by Courtney Deery Heritage Consultancy Ltd. to the National Monuments Service on behalf of Sherman Oaks Ltd. McLoughlin, G. 2019b Final Archaeological Excavation Report, Station Road, Portmarnock, 16E0613. Unpublished archaeological report submitted by Courtney Deery Heritage Consultancy Ltd. to the National Monuments Service on behalf of Sherman Oaks Ltd. Compiled by: Caimin O'Brien based on details provided by Gill McLoughlin of Deery Heritage Consultancy Ltd Date of upload: 21 June 2023