The Leinster Aqueduct and Kilcullen Mills

More exploration on this week's Sunday cycle trip along the canal.

 

Flood arch under Leinster Aqueduct. © Eugene Brennan

I was going to go as far as Digby Bridge, but it was 6.30 on a really gloomy day and I wanted to get back to Kilcullen before it got too dark, so I'm going to have a better look at this structure at a later date. This is the underside of the Leinster Aqueduct,  constructed in 1783, which carries the canal over the River Liffey, north of Sallins. There seem to be several of what look like flood arches at this section, quite high up on the river bank away from the main arches. The "New Bridge" at Carnalway (as it's described on the c. 1837 OSI first edition map, because there's an older 17th century bridge upstream on the Harristown estate) also has one or more flood arches on the northern side of the bridge. One of these is described as a "tunnel" on the later 25" c. 1900 map, with a track running between Newberry House and Harristown House. A corn mill is shown on the first edition map, but both the mill and mill pond seemed to have disappeared by the time the 25" map was published.  Further upstream, near the bridge that carried the Tullow branch of the GSWR railway across the River Liffey was Rochestown Corn Mill, visible on the first edition map. Again, by the 1900s, it had disappeared.

New bridge over the River Liffey at Carnalway. shown on the c. 1837 first edition 6" OSI amp. Map image courtesy OSI (Tailte Éireann)

 

Bridge over River Liffey at Carnalway. Map image courtesy OSI (Tailte Éireann)

Rochestown Corn Mill. Map image courtesy OSI (Tailte Éireann)

 

 Other 19th century mills in Kilcullen

 

On the subject of mills, in addition to the corn mill at New Abbey and in the centre of Kilcullen town, several are indicated on early Ordnance Survey of Ireland maps. There was a corn mill located in the fields between The Stray Inn/The Mill pub and the Green Avenue, also with a small mill pond to store water (the 19th century equivalent of a battery storage facility). This was fed by a mill race off the Mill Stream, splitting from the stream inside the grounds of Gilltown estate. No traces of the mill remain. Strangely, the New Abbey mill has no mill pond shown on the map, possibly because it no longer existed by the time the 1837 map was drafted. The area around the Mill Stream south of the road bridge is quite flat, so perhaps that acted as a natural reservoir to hold water, with flow controlled by a sluice further downstream. Alternatively If flow was sufficient and constant on the stream, maybe a mill pond wasn't necessary? The feed to this mill passed through an arched culvert under the road, a short distance south of the bend at the entrance to the cemetery. The mill was located just east of the wall around the cemetery, the ruin in the field possibly being part of the structure. There was actually what looked like a small small weir (although it may just have been a change in the level of the stream bed), visible on the south side of the bridge in the 70s. From what I can remember this was only around a foot tall (see photo from 1983 below), so possibly it was the remains of a taller structure. There was also a saw mill on the Gilltown estate and the current lake was possibly the mill pond that supplied water to this. Maybe someone knows the history of this? It's shown on the c. 1900 map. Other mills within a range of 7 miles of Kilcullen include a cotton mill at Inchaquire, just south of the turn for Colbinsttown on the R448 Colbinstown road and of course the woollen mill in Ballymore Eustace. There are an extensive collection of ruined mill buildings on this site.According to a 1906 Leinster Leader article, "The woollen mills of Ballymore Eustace were built by Mr. Christopher Drumgollee in the year 1802, and when in full swing employed 700 hands."

 

The Mill Stream, Kilcullen, south of the bridge on the New Abbey Road. The photo was taken in 1983. © Eugene Brennan

What were mill ponds for?

A mill pond acts like a buffer, analogous to the tank on an air compressor, the latter storing energy so that it can be released in large dollops when necessary, greater than a compressor pump could deliver on it's own. Anyone who worked in Renley Engineering may remember the flywheel on a punching machine, which had the same function. The advantage of a mill pond is that it can store water from a stream with a relatively low flow rate, even during the night, and a sluice gate can be opened to release a larger flow when required, greater than a stream itself could source. A weir has a similar function, backing water up behind a barrier, often on a river. A weir however raises water level so that the water gains potential energy because of its height. Some mills don't seem to have had weirs. Instead, a mill race carried water from a point further and often a long distance upstream where the water level was at a higher elevation.

You can view old maps on the OSI's Irish Townland and Historical Map Viewer here.

Map images courtesy OSI (Tailte Éireann)