Cormac's Mill at Tara, 275AD

Finding Cormac's Mill, the First Mill in Ireland.


I've always been fascinated by the Hill of Tara and it's surrounding landscape, not just because of it's importance as the centre of Irish mythological and historical events for thousands of years; -it's layer upon layer of archaeological remains, the ring forts, the wells, the burial mounds- but by something more intangible.

Fig (i) The Hill of Tara

The place has a hold on our imaginations that is hard to explain, and even people who have never read it's history can't help but feel a sense of magic and mystery when they walk between the ditches of the great Banqueting Hall or stand at the site of the Liath Fail and gaze down at the land rolling out before them. 

When we read the myths, the history and the folklore we start to realise that, despite what archaeology can reveal, there are still so many mysteries that remain.

But what has this got to do with Hydropower, I hear you ask?

For the answer to that question we have to step back to the reign of Cormac Mac Airt, who ruled Tara 1750 years ago, and under whose rule Tara flourished. The Irish Annals record the details of his reign in great detail, and it is in a text called the Metrical Dindshenchas (a description of the topography of Tara) that a fascinating tale emerges.


Temair III (verse 25-30)

It is there was situated

the house, on the margin of Nemnach;

about this house away across Meath

were scattered the houses of Temair.

Temair, whence Temair Breg is named,

Rampart of Tea wife of the son of Miled,

Nemnach is east of it, a stream through the glen

on which Cormac set the first mill.

Ciarnait, hand-maid of upright Cormac,

used to feed from her quern many hundreds,

ten measures a day she had to grind,

it was no task for an idler.

The noble king came upon her at her task

all alone in her house,

and got her with child privily;

presently she was unable for heavy grinding.

Thereupon the grandson of Conn (Cormac) took pity on her,

he brought a mill-wright over the wide sea;

the first mill of Cormac mac Art

was a help to Ciarnait.

Ciarnait was the captured daughter of a Pictish king who was brought from Scotland to Tara where she was forced to become a vassal slave in Cormac's court.  Because of her beauty Cormac fell in love with her, but Cormac's wife, Eithne, didn't approve and had her sent to work grinding grain by hand with a simple quern-stone.

When Ciarnait fell pregnant she went to Cormac and told him that she was no longer able for the heavy work so Cormac sent for a mill-wright from Scotland to design and construct a mill so that she would not have to labour for Eithne any more.  PW Joyce, in his 'Social History of Ancient Ireland' (1906) records the name of the mill-wright as MacLama, and he also records the location of the mill as being at Lismullin ('The Fort of the Mill')

Very early Irish tradition, transmitted through ancient manuscripts, assigns the erection of the first watermill in Ireland to the illustrious King Cormac mac Art (reigned A.D. 254 to 277). He sent "across the sea" for a mill-wright, who constructed a mill on the stream of Nith, flowing from the well named Nemnach ('sparkling') beside Tara. The spot on which this mill was constructed, and where a mill was kept working time out of mind until very recently, was called Lismullin (the 'fort of the mill'): and the place, which is a mile northeast from Tara, retains the same name to this day.

Lismullin has an association with milling that undoubtedly stretches back into antiquity, but I have serious doubts about it being the site of Cormac's Mill.  Not only does it not fit the location as described in the ancient texts, but it's also doesn't fit well with what was required by King Cormac.  

No doubt Lismullin was an excellent site for a larger more modern mill, but with a catchment of almost 15km2 and a mean flow of approximately 200 litres/second, it would have been far larger than what was required to replace the labour of Ciarnait, and not ideally suited to the technology of the time.  PW Joyce describes the way these early mills were operated in figure (ii) below.  These early mills were quite different from the far larger mills of the 17th and 18th century, and it was more typical for them to be supplied from a mill pond, than directly from a free flowing river.

Fig (ii), PW Joyce, 'Social History of Ancient Ireland' (1906)

Lismullin is also located on the Gabhra River, -into which the Nith stream flows-, but it would be stretching the description in the texts too far to say it is fed by the Nemnach well.

Fig (iii) Petrie's map of Tara with Nemnach shown.

So, if not at Lismullin,  where else could Cormac's Mill have been.  Let's return to the old texts.  The Dindshenchas clearly state that the mill was fed from Nemnach, a well located on the eastern slope of the hill of Tara.  In the 19th Century George Petrie created a map from the topographical information contained in the Dindshenchas, and I've included it here, figure (iii), with the well, Nemnach, clearly shown.

Nemnach is clearly described in the Rennes Dindshenchas as the source of the stream, Nith, on which the mill was constructed.

5. Nemnach, a well which is at the elf-mound in the north-eastern part of Tara. Out of Nemnach comes a stream named Nith. ’Tis on this that the first mill was built in Ireland for the benefit of Ciarnait, Cormac’s bondmaid.

...but it is also stated that in Temair III (Verse25-30) that the Mill was located in the glen of the Nith stream.  It is clear from a study of the maps, the topography, the description of the technology, and the description of the location in the texts, that the mill must have been located  at the head of the Nith Glen, south of 'Tara Hall'.

Fig (iv) The location of Cormac's Mill and associated Mill-pond (275AD)
(click image to enlarge)

ITN Coordinates (692531,759907), LEN (N926599), GPS (53.5808N, 6.6026W)


 I hope you have found this article interesting.  I'll revisit this idea again in the future, so please drop in again soon.  Any comments would be appreciated, and I'll always try my best to respond promptly.

And if you're curious about the potential to generate hydroelectricity in any stream or river throughout the country, why not check out the Map Survey on MicroHydro.ie.  It's a free and confidential service.