2003:556 - DUBLIN: 10 Mill Street, Dublin

Test excavation on a large site at Mill Street, Dublin 8, was undertaken in October and November 2003. The site includes a standing historic structure (10 Mill Street), which was the subject of a separate report.

The development site has frontage to Mill Street, Sweeney’s Lane, and flanks Warrenmount Lane and convent grounds. The development of this area is heavily influenced by the River Poddle, which powered many mills and serviced other industries in the south inner city from the medieval period onwards. The site of the medieval “Double Mill” of St Thomas’s Abbey, with its water channel and millpond, is located on the development site. The millpond (SMR 18:20(398)) was located to the west of the mill and the mill (18:20(92)) was sited towards the eastern end of the site. One channel of the Poddle led north-east around the boundary of the lands of St Thomas, and a mill, known as the Double Mill, was located on this branch. This is located on the site under study.

The first edition of the OS map shows the millpond, fed by the combined sources of the stream from the mill at Greenmount Terrace (annotated the ‘factory water’ on the estate map of the earl of Meath) and another branch down Sweeney’s Lane. The millpond at the site appears to have been visible as late as 1973, when Fitzgerald wrote: ‘it is of special interest to see today—still open and in the centre of Dublin—the Mill Pond belonging to the ‘double mill’ listed above. It is the last open portion of the Poddle still there, within hailing distance of Saint Patrick’s.’ She describes it as ‘about 3ft wide and 2ft deep with no sign of power or history at all, except where it finally cascades underground, under the former old mill at Warrenmount’.

The location of the trenches was determined by the perceived location of historic features, which included the mill building/s (Trench 1), early 18th-century buildings on Sweeney’s Lane (Trench 3) and the edge of the millpond (Trenches 2, 4 and 5). The locations were limited by the presence of live services, a culvert for the Poddle and the presence of standing buildings. All the trenches were excavated by a JCB fitted with a toothed bucket.

Trench 1 was located in the area of the two buildings indicated closest to the millrace on Rocque’s map of 1756. Two discrete groups of industrial features were uncovered in the trench, which measured 2m in width and almost 10m in length. Further investigative work is required in this area. The features uncovered relate to the industrial buildings last present on the site. They are likely to relate to the 19th-century mill on the site, which stood until the 1970s. This large mill building may have incorporated elements from the smaller mill depicted on Rocque’s map. These are likely to include the watercourses and wheel pits. None of these were exposed in the test-trench.

Trench 2, in the yard to the west of the millpond, uncovered a decayed timber pipe or drain. A sherd of 19th-century pottery was retrieved from the silt which filled the central perforation of the pipe. The pipe lay on subsoil.

Trench 3 was dug along Sweeney’s Lane. It was expected that evidence for the substantial houses built here by 1718 would be uncovered. Concrete overlay hardcore to a depth of 0.4m. This directly overlay subsoil.

No deposits were uncovered in Trench 4, which was located in the south-western part of the site, close to the west wall of the large modern building. It was expected that the retaining wall/s for the millpond would be uncovered. The trench measured 20m in length. The sides collapsed continuously throughout excavation, due to the unstable nature of the deposits uncovered. The trench was dug to a maximum depth of 2.5m, and the profile was consistent throughout. Very loose stone and brick rubble and loam, which included plastic debris of recent date, was uncovered. No structural features were evident. The material uncovered represents deliberate and rapid infilling of the millpond.

Further archaeological work is planned for this site.

Reference
Fitzgerald, A.D. 1974 Down the old Poddle. In E. Gillespie (ed.), The Liberties of Dublin. Dublin.

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