Quick lime, slaked lime – words for limestone that tell different stories, a remembrance of chemistry lessons. If limestone, CaCO3, is heated carbon dioxide is driven off to leave calcium oxide, CaO – quicklime or burnt lime – a crystalline, alkaline and caustic substance. If water is added the material hisses and spits, giving off heat, as it becomes hydrated to form slaked lime, Ca(OH)2.
From the words for these differing states of lime other tales are derived, of roadstone, mortar and plaster (1), slag from iron-making (2), and fertilising arable fields. And these tales of industry have their beginnings in the digging and blasting of limestone from the earth.
Limestone forms great blocks of geology around the perimeter of the Lake District: to the North-East at Penrith, further South at Shap, and to the West just inland from the coast. It is a Carboniferous rock that has its origins in warm shallow seas, when ‘Britain’ lay far to the South of the equator: single-celled animals, corals, brachiopods and shelled molluscs extracted calcium ions and carbon dioxide from the water and used them to construct their crystalline skeletons of calcium carbonate. When the creatures died, they fell to the sea-floor and over millennia were compressed and lithified. The continents moved and split, land masses rose, volcanoes erupted, and sea-beds were hidden miles deep. But erosion by glaciers and weather exposed them again and now there are limestone massifs halo-ing the Lake District’s mountainous hard rock interior – available for quarrying and (in the case of the precious limestone ‘pavements’ of clints and grikes) for conservation.
Small lime kilns are slotted into hillsides and escarpments like eyes, their brows an arch of brick or stone; single ‘pots’, or double, even triple, side by side, usually arranged so that broken limestone and coal can be fed into the top and, after the burning, quicklime scraped out from the bottom. The quicklime from these small kilns was probably used locally for spreading on arable fields and pastures, to reduce the acidity and improve the productivity of the land. (3, 4)
But there are several majestically large commercial kilns too whose origins were closely linked with not only the West Cumberland coalfields but also the large deposits of haematite or iron ore in the West of the county. Near where I live and well-hidden from public view are the Wardhall – or Warthole – limekilns.
The track runs straight, sloping gently downhill towards the River Ellen. It’s January and the fields are full of chocolate-brown Herdwick hoggs with white legs and faces, brought down from the fell farms to over-winter on the richer lowland pastures. In the way of Herdwicks, three of the young sheep have escaped and are browsing on the brambles along the track; they stare at us and, knowing they are doing wrong, sheepishly sidle back into their field, having remembered exactly where they broke the fence.
The track is firm underfoot and runs for nearly a mile, lined on each side by tall flailed hedges of hawthorn, ash and elder that, even leafless, limit the view. Then suddenly we are out, onto a flat area, glistening with ice and green with moss, that is raised above the river valley like a belvedere. There is an unconvincing rusty-wire fence at the abrupt edge – and a steep vertical drop, a cliff-face of dressed sandstone blocks. Although it’s impossible from here to tell, we’re on top of the kilns and although they are now covered over, we’re standing on the entrances to the pots into which coal and quarried limestone would have been dropped.
We back-track to a thin strip of damp woodland beside the track, and scramble down a bank, through brambles and the stalks and flat dry heads of cow parsley, frost-rimed; clamber down a low brick wall onto what might have been a platform or loading area, and then onto a plain of straggling grass and shallow moss-filled pools overlying rubble and broken brick. Now we’re at the base of the enormous flat front of the bank of kilns. The entrances to the four pots are like half-bottles, each framed in perfectly-cut and aligned sandstone blocks.
The interior walls are dank with green algae and liverworts, part-hidden by ivy. Scrubby, boggy ground and straggling ash trees make reaching the openings difficult – but at the back of each deep arch are small brick-edged openings, supported by rusting metal. In one arch the openings are blocked, one by horizontal rusty iron doors; another by a solid tumble of grey and black stones. These openings are the draw-arches or ‘drawing-eyes’ for the fire-pots, and the doors were used to control the air flow into the kiln; Graham Brooks (5) told me “it was a technical job trying to keep the temperature of the fire in the pot at the right temperature – too low and the limestone didn’t burn, too high and you could get a fused mass depending on the amount of secondary minerals in the limestone.” Limestone and coal would have been layered in from the top, “usually in the ratio of three limestone to one coal.” The quick lime would have been raked out, probably straight onto the waiting railway wagons. In two other arches, spectral effusions of white, streaked, limestone ooze out from the eyes – slow waves of calcium carbonate re-petrified – decorated with the jagged teeth of stalactites. Within the massive stone structure, the hidden pots of the kilns must still contain limestone – through which water has trickled down, dissolving the calcium salts, the concentrated brine seeping out year after year.
When lime-burning first started here isn’t clear, but Graham Brooks, in his research into Cumbrian limekilns (5), states that the Warthole kilns, “were rented out to the Gilcrux colliery company prior to 1852 when they were advertised to be let by Mr Richardson of Dovenby Hall. (The present kilns probably date to after this time.) The Solway Haematite Iron Company, Maryport worked the quarries and kilns in the 1870s.”
In other words, the 19th century limeworks were associated with coal and with iron ore, haematite – so the quicklime would have been used in the production of iron. If haematite is heated to high temperatures, molten iron is liberated – and the added limestone (which is oxidised by the heat to quicklime) or even better, quicklime itself, bonds with the impurities from the fuel (coal) and the ore to form slag, which floats on top of the molten metal (6, 2).
This was also the age of railway building, especially in Cumberland. Between 1840 and 1845, the railway from the coastal town of Maryport to Carlisle in the North was completed – the section from Maryport to the coal-mines at Arkleby (very close to Wardhall) was finished in July 1840 (7). The 25-inch Ordnance Survey map for 1865 (8) clearly shows the M&CR running alongside the River Ellen, with sidings that connect with a fan of four lines from the Warthole Limeworks (where, curiously, only three – not four – pots are shown). Also shown is the track that brought the limestone down from Warthole Quarry to the South-East of Warthole Guards Farm – this was the sloping inclined plane or tramway, down which rope-linked tubs laden with stone would pass, and down which we had walked between the wintry hedges. Gravity ensured the tubs would reach the flat area at the top of the kilns and, as they rumbled down the rails, their weight would pull a train of empty tubs back up to the top; the double line of rails midway as a passing place can be seen on the map, and there would probably also have been a winding-drum with a brake for the rope. Rails fan out to the rock-faces in the quarry, too. The deep quarry is still there, now partly obscured by a tangle of trees and vegetation.
But by the time the OS map was revised in 1891 (9), the M&CR sidings have been removed; Ward Hall Limeworks are marked as Disused, and the tramway is marked as ‘Old Wagonway’; there are no longer rails for tubs in the ‘Disused’ quarry. Iron and steel production was still centred on Workington, but cheaper iron ore was being imported from Spain and the economics of transport were changing rapidly; the M&CR’s Arkleby station was closed, the Solway Junction Railway (10) would also soon be closed.
Interestingly, the 2007 obituary of Donnie Bewick (11), a former neighbour of ours, notes that “During the war, Donnie drove for Gilcrux hauliers, Johnston Bros, many times leading lime into Scotland from Warthole limeworks, Plumbland.” Presumably he was transporting limestone taken directly from the quarry.
Here, then, is another lost story. There will surely still be local memories, some of which might go back a couple of generations, but at the moment Covid restrictions mean they can’t be accessed… Further details of the stories must wait.
Many thanks to my friend and industrial archaeologist Dr Peter Stanier (who also accompanied us to the kilns on our first visit in 2004) for useful discussions and weblinks.
1. ‘What’s a clay dabbin?‘: lime mortar and rendering; these houses are also covered in The Fresh and the Salt, the Story of the Solway, chapter 2, ‘Changeable Depths‘ (more photos on the related website).
3. An index, plus photos, of Cumbrian limekilns by David Kitching.
4. Graham Brooks’ website, Cumbrian limekilns.
5. My thanks to Graham Brooks for his email discussions, and for information about Wardhall kilns
6. British Lime website
7. The Maryport & Carlisle Railway, M&CR
8. National Library of Scotland, OS maps
9. NLS OS maps
10. The construction and destruction of the Solway Junction Railway: Crossing the Moss
11. Obituary, Donnie Bewick 2007