During my years working in the commercial archaeology sector and especially on the road schemes during the Celtic Tiger one monument which we would regularly encounter was the limekiln. On excavation of these sites, researching them and writing the report, it was noticeable how many have just disappeared from the landscape over the past 100yrs. Where ringforts, holy wells and tower houses etc have folklore associated with them and are to a degree protected, it is unfortunate to see these fine limekiln structures are vanishing from the landscape.
While working on the M8 road scheme some years ago I recorded a 65% decrease in limekilns across 26 townlands by examnig the first and second edition OS maps (approx. 1840-1913). This figure has no doubt increased even more since 1913 to the present.
The limekiln was a fairly common element of agricultural practice in pre-famine Ireland and was known and commented on as far back as 1640 when limestone was burnt to extract lime to fertilise the fields (Neary 2002). The majority of limekilns date to the 18th and 19th centuries (O’Reilly 2000) although some were still in use up until the 1940’s (O’Hara 1991). In one instance it is recorded that near Mullinavat, Co. Kilkenny in 1842 “……you come to a lime-kiln, where a guard of a mail-coach was seized and roasted alive” (Thackery 2005). The use of coal as a fuel for the limekiln would be a common occurrence and there is a history of coalmining of anthracite in places such as Castlecomer Co. Kilkenny starting in around 1640 (Neary 2002). The limestone needed was either quarried from bedrock or as cobles or boulders from the eskers and moraines of the midlands. It was also obtained from shells and shell sand from the seashore (Feehan 2003).
First it had to be broken into quite small pieces to have a successful burning. White and soft limestone is easier to convert into lime than for example the black limestone in parts of east Co. Clare. To burn the lime, a black bituminous dust called culm was used. If the limestone was too large it would not completely burn and would emerge from the kiln as a hard lump. These lumps were known as “coddlers” and were quite useless and would not have been able to be burnt again. Turf and timber was placed at the base of the kiln then alternate layers of stone and culm were put in the kiln until it was full. A covering of clay sealed the top. It might take up to a week to burn a full kiln. Through the arched alcove (púirín or discharge hole) at ground level the bottom layer of fuel was ignited so all the layers would burn eventually leaving a mixture of ash and whitened lumps of burnt limestone (quicklime) to be taken out through the alcove.
Quicklime was cheap and light to transport and was used sometimes in burying fallen livestock. Some farmers were also known to dip seed potatoes in lime before planting to give a better yield as lime or Calcium Carbonate is needed for acid soil. For its use as a fertiliser or for making building mortars the quicklime had to be slaked thrown into a pit of water. Evans writing in 1957 states that “the home burning of lime did not long survive the great famine and that down to that time wherever limestone could be obtained almost every farm or farm cluster had a lime kiln”. Most of the surviving lime kilns are constructed above ground however they also have ramps built to allow access to the top. It can be stated that lime assisted in land reclamation up to the modern era and helped increase the productivity of poor land.
Apart from agriculture,lime was used extensively to decorate houses, both inside and out. The properties of limewash were suited to the purpose, once dry it shed water quickly, so it didn’t simply run off the wall in the rain. Another more important view was that the limewash cleansed and killed bacteria, which it probably did considering it was now Calcium Hydroxide. Later on, people added colour to the limewash and it was not unknown for people to ask for Pink whitewash.
Evans, E. Estyn. 1957. Irish Folkways. London
Feehan, J. 2003. Farming in Ireland: History, Heritage and Environment. Roscrea.
Neary, P.J.H. 2002. “Archaeological excavation of sixth century burials at Cooleeshalmore, Threecastles, Co. Kilkenny”http://www.kilkennyarchaeologicalsociety.ie/archaeologyreport2a.htm
O’Hara, B. 1991. The Archaeological Heritage of Killasser, Co. Mayo. pp190-191. Galway
O’Reilly, B. 2000. “Briefing Notes on Lime kilns.” Unpublished: Dept of the Envirnoment, Heritage & Local Government
Thackery, W.M. 2005. The Irish Sketchbook of 1842. Dublin. pp44.