2013:615 - St Patrick's Cathedral, Dublin, Dublin

Monitoring took place at St Patrick’s cathedral during the construction of a new path and water-main along the northern side of the complex. The new section of path extended westwards from the Bride Street entrance in the north-eastern corner of the cathedral precinct, to join with the existing path running along the northern side of the cathedral. The new water-main was positioned to the north of the path, located along the base of the boundary railings between the cathedral and St Patrick’s Park.

This general area has seen considerable disturbance throughout the years, most notably during 19th-century restorations works to the cathedral and the adjacent grounds. One of the major projects was the general reduction in ground level around the cathedral (by approximately 2m/6ft) which was designed to expose the original base of the cathedral and reinstate medieval cathedral proportions. The works also included the demolition of the brick terraced houses that had been built up against the northern side of the cathedral at the eastern end, as part of the general slum clearance programme of the area. These houses were located east of what was originally called St Patrick’s North Close, a large open courtyard, which flanked the North Transept on the north and is depicted on Rocque’s map of Dublin, dated 1756. By 1877 it was decided to create a new park to enhance the setting of the cathedral and this involved not only demolition of the houses but the sweeping away of the large open courtyard. This work was quickly completed and by 1902 St Patrick’s Park was opened.

The new path was confined to the north-eastern side of the cathedral and, as previously mentioned, this extended from the high ground on the east (on the Bride Street side, which was not reduced in the 19th century) down the artificially-created slope to join with the existing concrete path (at the reduced ground level) that runs parallel to the cathedral along the northern side.

A number of pits were excavated along the route in advance of excavation for both the water-main and the path. At the eastern end the excavations revealed dark clay fill deposits sitting over crushed rubble to a depth of 1.5m (on the higher ground, which not reduced in the 19th century) while on the western side (where the ground was reduced) the excavation revealed brick drain structures lying just 0.3m below present ground level. Both the rubble and the drains were clearly associated with the terraced housing at St Patrick’s North Close, removed to make way for the park.

The water-main trench, which extended as far as the western end of the North Transept, measured, on average, 0.6m in width by 0.8m in depth and was excavated by a combination of hand and machine. It ran along the green grass verge at the base of the northern boundary railings and was widened slightly at several places where existing services were tied in. As the trench extended through what was previously the open courtyard, the findings were dominated by drains and a total of three were identified ranging in date from the 18th century to the early 20th century.

Brick gully
The base of a brick gully was located at the join of the old and the new path and this lay 0.3m below present ground level. This gully was relatively modern, composed of modern brick and partially concealed by a concrete foundation that ran along its southern side. It extended for over 30m in length and was exposed in three separate sections. The side walls of the drain were gone but the base was in situ and this had a slightly raised ‘lip’ at either side. The gully was set in green clay mix, which could be dated to the 17th century and was backfilled with loose brown clay. A small collection of human remains, including two skulls and two lower mandibles, was found in a neat pile in the backfill of the gully, obviously originating in a disturbed graveyard fill material. These bones are likely to be related to the lowering of the graveyard previously mentioned in the mid-19th century.

Limestone drain
A far more substantial stone French drain was exposed lying further east along the trench and this was positioned 0.8m below present ground level, sealed by green mixed clay, which contained post-medieval finds. It was cut into re-deposited yellow clay, which is likely to be dated to the late 17th century, but the drain is probably mid-to-late 18th century in date. This drain was orientated north-west/south-east and was exposed for over 2.8m in length. The north-western end was removed when a concrete pier was constructed to support a flood-light while the eastern end extended beyond the limit of the trench on the southern side. The drain was a good solid construction but the capping stones did not survive. On investigation, it was revealed the drain measured internally 0.55m in width by 0.5m in depth and the walls were composed of large roughly-hewn block of limestone, some as large as 0.3m by 0.4m. The drain was heavily mortared with a distinctive gritty lime mortar, bright yellow in colour, and was filled with a pure black silt deposit, which contained organic fragments. A small trench was excavated through the fill of the drain and this revealed a neat limestone flagged base. A small patch of rounded cobbles, averaging 0.15m in diameter, could be identified in the north side of the trench, just above the drain and these may have represented the remains of the cobbled surface of the courtyard mentioned above.

Brick and limestone drain
A third drain was identified further west but this was a different in type, orientated east-west and lying 0.7m below present ground level. It was exposed for 1.9m in length and had been badly damaged in the past, with no evidence of capping stones surviving. On investigation, it was found to measure internally 0.45m in width but was but was only 0.14m in depth and had clearly been truncated at some stage. In addition to this, it had been badly damaged at either end. The south wall was built of a coarse orange brick, two courses in height and mortared with a yellow gritty mortar while the north wall was composed of small limestone of various sizes, averaging 0.1m by 0.15m, and unlike the massive blocks of the previous drain. The brick, therefore, may represent a repair. The drain was filled with a loose rubble demolition material rather than silt and there was no defined floor. A modern brick culvert was also found to the south-west of the drain, lying at 1.1m below present ground level.

The south-west corner of a build?
The trench terminated just west of the Boiler House (north of the west end of the North Transept) where the trench turned southwards across the path, tying into an existing service on the southern side. This trench, orientated north-south, had been opened previously as there was 804 stone fill at the base. At the southern end it terminated at a manhole which forms the entrance into an underground culvert/passageway that extends under the cathedral running north-south and is accessible (if somewhat cramped) by foot. Part of the brick manhole chamber (previously truncated) was also exposed and this was found to have been damaged, presumably by the previous trench.

On inspection, the brick chamber was found to have damaged an earlier stone feature, which was possibly the south-west corner of a limestone building lying approximately 0.5m below present ground level. The southern wall was exposed in section in the western side of the trench where the previous trench had been excavated through it. This wall was composed of large limestone blocks, measuring, on average, 0.3m by 0.4m, with a series of smaller stones within the core of the wall. It measured 1.3m in width and it survived to 0.36m in depth, the width suggesting it may possibly have been medieval in date. It was mortared with an off-white creamy loose mortar with visible limestone fleck at the southern end, slightly whiter in colour at the northern end.

The eastern wall was also exposed, lying 0.5m below present ground level and was similarly constructed, although orientated north-east/south-west suggesting that the structure was orientated similarly, at a slight angle. This wall was exposed for 0.8m in length and was well-faced, composed of large massive limestone blocks, measuring, on average, 0.22m by 0.5m, and bonded with the same mortar as the southern wall. On investigation, it was found to be bedded on re-deposited clay, which contains a large number of limestone fragments, measuring, on average, 0.15m in diameter.

The building is likely to be medieval in date by type and form, and the limited investigation carried out on the clay beneath the wall found no evidence of brick or later finds, as elsewhere. No building is represented cartographically in this location, Rocque’s map of 1756 depicting the courtyard mentioned above directly north of the transept. ***The slight north-east/south-west angle of this possible build is very interesting as it matches the angle of the Minot Tower, the 14th century tower of the cathedral, which is positioned at the north-west corner of the main cathedral building but is external to the nave. The fact it is angled differently to the nave is something of a puzzle. It may suggest the tower was influenced by a building orientation now gone in this area or that the tower incorporated an early structure, which dictated the footprint of the tower.

Clarke has suggested that the late 12th century collegiate church, built by John Cumin, the first Anglo-Norman archbishop of Dublin, may have been built in this location, replacing an earlier stone church (such as that found at St Michael le Pole at Golden Lane and dated to c. 1100). This collegiate church may have been replaced subsequently by the new cathedral in the 13th century. However, O’Neill has potentially identified late 12th century architectural features in the original western elevation of the nave, as recorded by Carpenter before the restoration began. This may suggest that the collegiate church was incorporated within the present cathedral building in the 13th century, the church continuing to function at the eastern end while the cathedral was under construction. In any case, the stone build whether a building or precinct wall, does confirm that there was an earlier north-east-south/west orientation in this general location, dictated by building now gone.

Bibliography

Clarke, Howard 2009 ‘Cult, Church and Collegiate church before c. 1220’ in J. Crawford and R Gillespie (eds), St Patrick’s Cathedral, Dublin: A history. 23-44. Dublin.

O’Neill, Michael 2009 arthur O’Neill, Michael 2009, ‘The architectural history of the medieval cathedral’, in J. Crawford and R Gillespie (eds), St Patrick’s Cathedral, Dublin: A history. 96-119. Dublin.

28 Cabinteely Close, Old Bray Road, Cabinteely Dublin 18