2003:466 - PELLETSTOWN AND CABRAGH, Castleknock, Dublin

Monitoring was undertaken across Phase 1 of a 19.2ha mixed-use development by Ines Hagen (January–February, 2003), Eoin Corcoran (February–August) and the writer (August–December). The development is bounded by the Royal Canal (construction begun 1789) to the south, River Road to the north, Ashtown Road to the west and Ratoath Road to the east. The development is between H.S. Reilly Bridge (1792), over the canal, at the development’s south-eastern end and Longford Bridge (1790) at its south-western end, with lock-keeper’s houses at the 8th, 9th and 10th locks along the canal.

The development consists of two sites: Pelletstown West and Pelletstown East. Pelletstown West is the larger of the two sites and, in addition to land lying within the townland of Pelletstown, incorporates a small section of Cabragh townland, located to the south-west of Pelletstown House. The land is generally flat to the west of Pelletstown House, but slopes steeply along the northern development boundary to the east of the house, where quarrying took place, closer to the Tolka River. Pelletstown House, its late 19th-century gate lodge and the immediately adjacent lands are excluded from the development. Pelletstown House dates from at least the mid-18th century, but underwent significant renovations at the turn of the 20th century. Longford Bridge is to be widened to accommodate traffic. A photographic survey and historical/archaeological report of that bridge has been completed by Franc Myles. A total station survey of the bridge has been completed by Kieron Goucher and Liam Murphy.

Pelletstown East was completely under grass prior to development. The land is flat to gently sloping, except in proximity to the River Road. Here, the land falls away more steeply towards the Tolka River. Steep slopes also occur in the proximity of the former 19th-century buildings near Cardiff’s Bridge (itself a monument of medieval origin, SMR 14:75), a result of human activity (quarrying, etc.). Depressions or sinks, again the result of (post-medieval/modern) quarrying, were visible in the north-east of the site, along a former hollow access way. H.S. Reilly Bridge and the lock-keepers’ houses were excluded from development.

East and south of Pelletstown House, much of the landscape appears to have undergone moderate to severe truncation. The truncation of the site is likely to be a result of five main factors. First, the landscape has clearly suffered as a consequence of plough damage (and subsequent aggravated erosion) dating from the 18th century onwards. Other landscape evidence—the regularity of the fields, their relatively even surfaces, the nature of the field boundaries, the removal of boundaries and agglomeration of fields, the widespread presence of dendritic, stone-filled field drains—suggests a keenly ‘improvement’-minded landlord in residence at Pelletstown House at some time in the past 250 or so years.

Second, there is evidence that major engineering works which accompanied the construction of the Royal Canal and, perhaps, the laying of the nearby railway line south of the canal altered the immediate landscape quite dramatically. For example, the land alongside both, at the south boundary of the development, had been levelled at some time in the past. Also, the base of the hill down from and east of the burial site (Frazer, No. 467, Excavations 2003) on the Pelletstown East site was severely scarped and levelled. Post-medieval pottery found at the eastern base of the hill during monitoring suggests this may have occurred first at or shortly before a time frame of c. 1790–1830. A modern drainpipe pre-dating the present development also runs nearby, along the lip of the vale there.

The third factor is the quarries at the eastern end of the development (Pelletstown East) and in the field north-east of Pelletstown House (on the Pelletstown West site). This quarrying scarped, respectively, the eastern and north-eastern hillsides at the eastern end of the development (where they were once accessed by a former hollow way) and the ‘Brick Field’ (see below) immediately east of Pelletstown House.

Fourth, the complete removal of 18th- and 19th-century buildings and field boundaries (including field ditches and foundations), which are represented on historic maps as having once stood near the historic ironworks by Cardiff’s Bridge, suggests major excavation and landscaping activity sometime after c. 1870. Pelletstown House underwent major rebuilding/renovation in this period, and it seems reasonable to posit that this era of change and development at the Big House might also have included other projects elsewhere in the demesne grounds. This factor may be one and the same as the first, outlined above.

Finally, recent investigations by the National Museum, including a meeting on the development site with a metal detectorist and the NMI (L. Shine, pers. comm.), suggest that Pelletstown and parts of Cabragh townlands have been subjected to intensive and exhaustive illegal metal detecting, possibly for more than a decade.

Three unenclosed human inhumations were discovered during monitoring on the Pelletstown East site (No. 467, Excavations 2003).

The post-medieval landscape
During the course of the meeting mentioned above, the metal detectorist tentatively identified an area near the ‘Brick Field’ (so identified on the first-edition OS 6-inch map) as being the findspot for an illegally acquired small Early Bronze Age copper alloy flat axehead and a small copper alloy awl that may have served as a prehistoric metalworking tool (the finds are now in the possession of the NMI). However, subsequent monitoring of topsoil removal in the location of the alleged finds indicated that the site served as a (sand?) quarry in the early/mid-19th century, during which time a small amount of rubbish had accumulated in its base. While the prehistoric finds are probably from Pelletstown, the alleged specific find’s location identified by one of the metal detectorists seems unlikely, unless the artefacts had already been removed from their original context at some time during the post-medieval/modern period. As no evidence for brick production survived in the Brick Field, it is tempting to see a link between the quarrying activity and brick-making activity elsewhere on the Pelletstown East site. Perhaps the Brick Field was also used for the storage and drying of bricks made elsewhere, although there is no direct evidence for this.

Other former quarries or possible former quarries, besides those in or near the Brick Field, were concentrated at the north-eastern end of the Pelletstown East site. These may relate to brick-making activity elsewhere on the site, or to the nearby late 18th- and 19th-century ironworks at Cardiff’s Bridge, just south of the site. One of these was accessed by a former hollow way that extended west from the eastern edge of the site, near the present Ballyboggan and Ratoath Roads junction, turned north, and exited the site near the River Road/Ratoath Road junction. As with the quarries in the Brick Field, these may be tentatively dated by rubbish that accumulated in their base; in this case, they may be slightly earlier, dating to between the last quarter of the 18th century and the first two-thirds of the 19th century.

Across Pelletstown West, field boundaries consisted of hawthorn, bramble and assorted young to mature trees (ash predominantly). On the Pelletstown East site, many of the field boundaries have been removed, but some survive as substantial banks and ditches, now smoothly grassed over. There is no pattern in construction methods or morphology distinguishing obvious post-agricultural improve-ment boundaries (i.e. those built after c. 1750) from some of the outer, curvilinear boundaries that may be fossilised relics of earlier demesne boundaries for the castle north of the site (SMR 14:74), in Cardiffsbridge Park. The boundary between the Pelletstown West and Pelletstown East sections of the development consists of a very late post-medieval/modern deep, wide, water-filled ditch, with some shrub growth present on its eastern side.

A number of former field boundaries removed and backfilled during the late 18th, the 19th and the early 20th centuries were uncovered during monitoring. Many, though not all of them, are likely to date to a roughly contemporary era of field agglomeration. Similarly, modern field drains and dendritic post-medieval/modern stone-filled drains criss-crossed some areas of the development. Many of the stone-filled drains also date to an approximately contemporary era of land improvement. Lintel drains near the lock-keeper’s house at the 9th lock are likely to date to the late 18th/early 19th centuries. Fields at the western end of the Pelletstown West site were criss-crossed with furrows orientated along the main axes of the fields, in perpendicular systems. They were created by a mechanical plough and respect field boundaries still standing at the time of monitoring. The crosshatch pattern may be another indication of improvement-minded agricultural practice on the demesne of Pelletstown House. More speculatively, the cross-hatch pattern may indicate ploughing subsequent to fresh field clearance, carried out to break up the ground and turn up bushes and tree roots; from the description of the demesne lands of the castle in Cardiffsbridge Park, it is evident that some of its land served as managed woodland (as the townland name ‘Cabragh’ also suggests), and it is quite possible that such use persisted into the post-medieval era, particularly if there was nearby industry requiring large amounts of charcoal fuel. Visible furrows were often absent elsewhere on the Pelletstown West site and across the Pelletstown East site, possibly another indication of more severe truncation and erosion in these areas.

Several large, oblong spreads of brick dust with evidence of in situ burning can be interpreted as makeshift brick clamps (up to 18m long in one case, but more typically 7–10m long by an average 3.5m wide, and up to 0.45m deep). Other smaller spreads of brick dust and burning were only possible clamps. Both clamps and possible clamps were concentrated in the south-eastern part of the Pelletstown East site, not far from the Royal Canal, and also not distant from the site of the Cardiff’s Bridge ironworks. The clamps consisted of an upper layer of orange brick dust mixed with brick fragments, 0.05–0.1m deep; atop a moderately compact layer of charcoal, up to 0.25m deep; atop a layer of burnt dark-reddish-brown subsoil, as much as 0.15m deep. No evidence of a more permanent kiln structure was found. Potsherds and clay pipes within some of the clamps date them to some time at the end of the 18th century or the start to middle of the 19th. They do not appear to have involved brick firing on a large scale, and may relate to either or both the canal or the ironworks. Work elsewhere in the Dublin area has identified similar brick clamps near the Grand Canal (e.g. by Ed O’Donovan and Red Tobin, Nos 606 and 620, Excavations 2003), where there was also an obvious transport benefit. The evidence at Pelletstown does not suggest large-scale industrial production, but rather brick-making for nearby industrial needs or perhaps for local (Ashtown) construction.

Several charcoal spreads in Pelletstown West and East, and three proper oval or subcircular fire-pits near a remnant field boundary along the north boundary of Pelletstown East, bear witness to unspecified fire-related activity. Nineteenth-century pottery from the spreads and pit fills indicates a post-medieval date, but its function remains unclear. No slag was found in the fire-pits, which were all less than 0.8m across (and usually 0.4–0.6m in diameter) and filled with charcoal and ashy deposits atop burnt subsoil.

No significant artefacts were recovered from the topsoil, although a number of typical potsherds and clay-pipe fragments were found, all post-medieval. These finds are obviously not a statistically representative assemblage, and they were recorded by just two of the three directors. However, some general observations about dates may be made. Approximately 85% of the topsoil pottery recovered from Pelletstown East dates from the middle of the 18th century or later. Of the remaining 15%, nearly 8% could also be from the later 18th century, but cannot be definitively dated thus. Of the pottery recovered from the topsoil on the Pelletstown West site, approximately 95% dates from the mid-18th century onwards. With only a few exceptions, all of the clay-pipe fragments that could be dated with reasonable precision date from about the second third of the 18th century or later. Several of the 18th-century pipe-bowl fragments recovered, particularly from the westernmost three fields in Pelletstown West (nearer Pelletstown House), were of Dutch origin, but otherwise the clay-pipe remains from the topsoil were unremarkable. The date profile of topsoil finds that were recovered does not contradict the other landscape, historical and archaeological evidence, which suggests significant activity across the Pelletstown development (the demesne of Pelletstown House) after c. 1750.

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