Borrow a rock from the site of a former quarry on the outskirts of Glasgow. Walk with the rock to a building in the city where stone from the quarry was used in its construction.
From Ashgill Road, near the site of the former Coltmuir, North Colt Park, and Kenmure quarries, Bishopbriggs to the University of Glasgow, Gilbert Scott building, Gilmorehill, Glasgow.
4 May 2021. Drifting with Paul Bishop, Emeritus Professor of Geomorphology, University of Glasgow. Minty Donald.
The starting point is a raised embankment of scrub and trees that runs along one side of Ashgill Road. It is where Bishopbriggs meets High Possil, to the north of Glasgow city centre. Paul pulls up in his car and puts on his wellies. The embankment runs between a housing estate built in the 1950s and another from the 1980s, which occupies the site of Coltmuir Quarry. Coltmuir was one of three quarries in this area; the others, North Colt Park and Kenmure. These quarries supplied blonde sandstone for buildings erected in Glasgow during the second half of the 19th century, among those, dressing stones for the University of Glasgow’s Gilbert Scott building on Gilmorehill campus.
There are some outcrops of sandstone in the grass and scrub embankment, among a jumble of scrap metal, plastic, crumbled brick, tiles, porcelain, and stone that has been dumped in the quarry site. Sandstone quarried nearby and used to build housing might have found its way back, as rubble from demolished tenements, to this or other spent quarries in the city.
I remember reading about a geological category called ‘artificial ground’, first recorded in geological surveys in the 1980s. Artificial ground includes ‘made ground’ like this embankment; ‘worked ground’, which comprises quarries and cuttings; and ‘infilled ground’, which is cut away ground that has been partially filled. I think about the Anthropocene — the idea that the impact of humans on the Earth’s ecology and climate is so dominant that it should be classified as a geological epoch.
The sandstone formed here was deposited by a vast river system that flowed through this landmass around 350 million years ago, Paul says. River sand accumulated in broad and slowly subsiding basins or troughs and, through pressure and chemical reaction, became compacted into the soft, beigey-gold, easily-workable stone that characterises much of Glasgow’s architecture. Sand deposited by river systems, or transported by wind, is sculpted by fluvial or wind movement into generally uniformly-sized and rounded particles. In some blonde sandstone, traces of organic matter are visible: deposits from ancient rivers. The distinctive lines common in both Glasgow’s blonde and red sandstone are also markers of ancient transport by wind (red sandstone) and water (blonde sandstone). Layers of sand were built up at different angles by ripples and shifting dunes in a process called cross-bedding.
I think about the spatial and temporal scales of the geological and the urban. Some changes to the urban environment are readily noticeable to humans — when a favourite building is demolished, for instance — while countless others occur on scales too small or vast, too slow or fast for humans to perceive unaided. Judith Lawson, in her book, Building Stones of Glasgow, draws attention to tiny, often overlooked features of the built environment — dune cross-bedding, black carbonaceous layers in cream sandstone — that point to geological events shaping the fabric of the city.
Some sandstone near here was quarried, or mined, using the ‘stoop and room’ technique, Paul says. In this technique vast caverns were carved underground with stone pillars left to support the rock roof. This costly method of extracting stone was viable due to the huge demand for building materials during Glasgow’s rapid expansion in the 19th century.
I find a piece of sandstone, about the size of a brick, beside one of the outcrops. I ask the rock if it will come with me, to follow the path of a former tramline towards the Forth and Clyde Canal. The stone stays silent but I decide to bring it along in any case. I think about myself as a flow of glacial ice, displacing the sandstone from its originary bedrock to deposit it somewhere else — to become an erratic, a rock out of place. Or maybe I’m performing a small act of extraction.
Walking along Castlebay Street, past some high-rise flats, heading towards the Forth and Clyde Canal, Paul says: ‘imagine this place in the mid-to-late 19th Century, heaving with tramways, and noise, and workers, and steam shovels’. There is a street of terraced houses. Paul notices that some are built of sandstone. Is it local stone? The style of the houses resembles colliery rows; there were coal mines nearby in the 19th century. But these houses seem too modern. (A check of historic maps confirms that the terrace was built in the 1950s, around fifty years after the coal mines closed. Perhaps the architect was referencing local industrial heritage?)
Heading across some scrubland, looking for traces of the former tramline that was used to transport sandstone from quarry to canal, Paul talks about his fascination with edgelands like this. Often, in the west of Scotland, these are post-industrial sites, ‘palimpsests, with layers and layers of occupation’. This one, undeveloped for whatever reason — contamination? too marshy? — forms part of a green-brown belt around the city.
Traces of the tramline become elusive. Expectations of finding a narrow strip of slightly-raised land continuing across the boggy ground — perhaps still used as a pathway — are confounded. Perhaps the other other end of the tramline, at the canalside, might offer a clue. There may be the remains of a jetty or quayside loading point beside the waterway. Squelching through marshland in his wellies, heading towards the canal, Paul says that this boggy ground was likely to be a ‘glacial legacy’ created when a glacier or ‘dead ice’ from the last Ice Age finally melted and left a poorly drained hollow. Dead ice is a large chunk of frozen water left behind as the ice sheet melts, which itself takes hundreds or thousands of years to melt. Paul says that this type of boggy ground is called ‘deranged drainage’; it’s not part of a river network.
At the canalside, there are the sandstone footings of a row of miners’ cottages: Kenmure Row. The row of cottages stood here from the 1860s until at least the 1930s. Among the sandstone there is a chunk of granite: an erratic deposited here by human, or glacial, forces? Further along the canal are vestiges of a stone jetty. Nearby, beside an electricity pylon, traces of three tracks form a triangle: a turning point for the tram carts used to haul stone to the canal. The grass near here is charred black. Piles of bottles and cans mark it as a local drinking spot.
Cutting sandstone blocks at the quarry was not likely the job of stone masons, Paul says. The stone was probably cut to standard sizes, moved by horse-drawn tram and canal barge, and worked onsite by masons. Paul describes watching the restoration of the Gilbert Scott building at the University of Glasgow, where highly-skilled teams of masons worked the sandstone onsite. As well as providing a good visual match, sandstone for restoration projects needs to be chemically compatible with the original building stone, otherwise weathering of the stone will occur.
I wonder where the stone for the University restoration came from, now that these quarries are spent? I wonder where the masons learned their skills and how sustainable the process of restoration is?
I lay my stone by the jetty, thank it, and say goodbye. It stays silent.
7 May 2021. Drifting with Lizzie Smith, architect. Minty Donald.
The starting point is the Forth and Clyde Canal at Stockingfield Junction, beside the mouth of a tunnel where Lochburn Road passes under the canal.
I bring with me the rock I borrowed from Coltmuir Quarry in Bishopbriggs on 5 May. I walked with this rock from the quarry to the University of Glasgow’s Gilbert Scott building. The rock accompanied me as I followed the same route its kin would have taken in the 1860s, when transported from Bishopbriggs for use as dressing stones for the facade of the then-new university building. The rock and I travelled together along the Forth and Clyde Canal and through Glasgow’s West End. I feel quite attached to this rock. Sometimes on the journey, swapping the rock from hand to hand to relieve my achey wrist tendons, I wished I had invited a smaller rock. But its heft also felt reassuring, like the sandstone blocks from which much of Glasgow is built, like those forming the canal tunnel through which we now walk.
Most of the stone used in building today doesn’t have the same properties as those solid sandstone blocks, Lizzie says. It is usually a veneer: a thin layer with no structural integrity that is applied to a facade, and which Lizzie calls ‘slip’. Slip has a mainly aesthetic function. Solid stone is generally only used in renovation projects.
I wonder, is sandstone veneer the same material as sandstone block? Has the veneer been so processed as to have become something else?
Maryhill Burgh Halls, standing at the corner of Garbraid Avenue and Maryhill Road on the route from the canal to the university, is a blonde sandstone building dating from 1878. It was saved from demolition and refurbished between 2004 and 2012. It looks ‘honest’ in its use of materials, Lizzie says. The sandstone, it seems, is what it is: solid, robust, and stoney. Stone buildings seem easy to understand: humans have been building in stone for eons; stone is not manufactured, it just comes out of the ground. But the apparently stout outer walls of the Burgh Halls are likely to be fascia, with rougher sandstone, rubble-stone, and brick forming inner linings.
I think about how artists, or architects, talk about the ‘honesty’ or ‘truth’ of a material. What does that mean? I wonder, how thick is the skin of a building? Someone asks us if we are lost.
Across from the Burgh Halls is a brown brick building, housing a Glasgow City Council Council Tax and Housing Benefit office. It looks like it dates from the 1980s or 1990s. Its brick walls are stark and featureless, broken only by small, grated windows. It is fascinating, Lizzie says — like a horror movie. What design decisions led to this being built?
In some streets on the route, light blonde sandstone tenements sit next to those where the sandstone is sooty black. The darkened, uncleaned buildings have ‘added charm’, Lizzie says. The squeaky clean ones, she feels, can seem quite bland. Why was there such a drive to clean up Glasgow’s buildings? To change the city’s image of pollution-riddled heavy industry to one of shining modernity? And why did some buildings miss, or opt, out of cleaning? Some sandstone buildings have scarification and damage due to aggressive stone-cleaning techniques. Early efforts to remove soot layers involved the use of acids and high-pressure grit-blasting, which left harmful chemical residues and made the sandstone more vulnerable to weathering. Glasgow’s high rainfall already has a detrimental effect on sandstone but this is likely to worsen due to climate change, which will bring even wetter weather to the city.
I remember visiting Glasgow city centre as a child in the 1960s and my mother pointing to the dark, ‘dirty’ buildings. Two decades later, I again walked around the city centre with my mum, who was astonished and delighted by the light, clean facades. I think about trends in urban planning, architecture, and heritage conservation. I wonder if fashions are changing to embrace the ageing and patinating of the built environment? Is there a turn away from the kind of emphatic interventions needed to keep buildings looking clean and new, to an acceptance of processes of change and ruination? An acceptance that ‘to remove the time stain is to harm the actual thing’, as Timothy Morton puts it?
In the Wyndford Estate, a housing complex built in the 1960s on the site of Maryhill Baracks, there’s an area of ground outside a block of shops that is filled with a forest of concrete bollards. The bollards come in three types and look like they have been installed at different times.
I wonder, why are these here? Why so many? What was the issue to which the solution was ‘we need more bollards’? What form might a creative response to this extraordinary urban feature take? A very precise form of parkour? A yarn bombing spree?
Architects don’t deal very well with how they communicate their choices about materials, Lizzie says. When presenting design ideas, materials are often left out of the conversation. Architectural models and drawings don’t portray tactile, material qualities well either. Decisions about materials are often made quite late in the design process, through weighing up ‘context, an architect’s sense of what’s right, cost, and maintenance’. But ‘materials cause lots of disagreements and lots of strife — during design stages, construction, and afterwards’. Architectural practices, like the one for which Lizzie works, now consider the sustainability of materials: the consequences of extraction and manufacturing processes. This is rarely part of public consultation.
I notice a patch of sandstone on a tenement wall where the surface looks like it is de-laminating, a layer peeling off the surface. I resist a strong urge to pick at it and pull it off, like a scab. I feel the texture of the rock I am carrying, crumbly to touch. I think about the large chunks of sandstone that recently fell off the front of the Mitchell Library in Glasgow, near where I live. The falling masonry, with great good fortune, missed pedestrians in the street below.
The end point is the South Front of the Gilbert Scott building. While the finer quality dressing stones for the facade came from quarries in Bishopbriggs, most of the stone used in the university building’s construction was quarried nearby. About seventy percent of the sandstone came from quarries less than a kilometre from the Gilbert Scott building. The University of Glasgow had a four-to-five year contract to extract stone from this area, under what was, until recently, the site of the Western Infirmary. Early stone construction followed what Paul calls the ‘four hundred metre rule’. Until transport systems like canal and rail networks were developed all building was in local stone. The use of blonde and red sandstone throughout Glasgow reflects the evolution of transport in central Scotland. Much of the blonde sandstone comes from quarries like those in Bishopbriggs, which were accessible by canal, while red sandstone from Dumfries and Galloway or Ayrshire was used in buildings constructed later, when rail networks connected the city to more distant sources of stone. Now, granite and marble veneers are imported from China and South America.
I wonder what the built environment might look like if a four hundred metre — or even ten mile — rule was introduced now? How would a focus on local materials shape the construction industry and architectural practice today? But what is ‘local stone’, when ancient ice flows transported boulders — glacial erratics — hundreds of miles from their originary locations and deposited them in places where the bedrock was of a different lithic type? As Doreen Massey asks, ‘How long do you have to have been here to be local?’
I choose a ledge on the Gilbert Scott building’s Victorian Gothic facade. It looks like a good resting spot for the rock that has accompanied me on my walk. I gently place the rock on the ledge, thank it, and say goodbye. I wonder how long it will stick around.
References: Doreen Massey, For Space, London: SAGE Publications Ltd., 2005, p.149; Timothy Morton, Being Ecological, Milton Keynes: Penguin Random House, 2018, p.169; Judith A. Lawson, Building Stones of Glasgow, Glasgow: Geological Society of Glasgow, 1981.