Travels in Conservation…Look Inside

Here is a small sample of the 1,300+ images and 160,000 words

What's under our feet...

Chedworth Roman Villa

The steps and walls in this pictures are genuine Roman work. The copings are another matter. At some stage in the late twentieth-century the York stone copings in the left image were added to protect the walls from frost damage. Hard edged, straight and obviously machine cut, these slabs were extremely honest, though it is not clear how well they kept the core of the wall dry.

 But they’re not there now (2020). They have been replaced by new Cotswold stone slates. It’s hard to see any real advantage in swapping one stone for another: each has its own advantages. The York stone was machine cut and likely to be more effective at keeping water out. It was also significantly more honest in that it had no pretence of being original. The Cotswold stone is not at all honest and is likely to make the casual visitor think that the wall tops are as time has left them, rather than being deliberately created new copings. It is unlikely that the Cotswold stone slates will prove as durable as the York stone, and it is highly likely that the irregular jointing will admit more water into the core of the wall.

If the technical advantages of the new coping are not obvious, why was it done? None of the site staff seemed to have any clear idea. Was the change fashion driven? A casual, possibly fashion driven, reappraisal of the importance of presentation over honesty.

Tewkesbury Abbey

We are not wrong to want high quality music in our churches, but…

…As a piano it’s grand, but we are wrong to put 1500 kg of piano onto hard wheels and trundle it around without thought to floor damage.

Winchester Cathedral

These are a foremost example of the problem of delicate and ancient floors. Winchester needs visitor revenue, but it doesn’t need visitor feet walking on its tiles. For cultural reasons, which baffle me, we are unable to insist that visitors take off their outside shoes before walking on a medieval work of art.

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Winchester Cathedral

The tiles at Winchester Cathedral have a narrative that is too complex for this document, save to say that instead of managing visitor footwear the Cathedral chose to try and reinforce the tiles with acrylic resin…hence the shine. No comment.

Unintended consequences...

 Lincoln, hidden defects revealed by cleaning.

Removing dirt often has unhappy consequences. Cleaning here has merely served to highlight the poor quality of extensive repairs. The repairs were placed into a building that was already dirty and were coloured to match the dirt. The mortar has been coloured black throughout its depth and can’t be bleached.

East Gate, Lincoln, cocktails.

The paler areas show where recent frost damage has disrupted the surface of the stone. This masonry was buried in polluted soil which has introduced significant quantities of soluble mineral salts. As the stone dried out after archaeological exposure, these salts have crystallised and weakened the stone to the point where it is frost susceptible.

Even allowing for additional decay drivers, the frost behaviour of some stone is simply mysterious and unpredictable…

. Tarrant Crawford, biocide run-off.

You probably shouldn’t use it even if you can control where it is going. The chemical industry does not have a good, or even honest, record over the long-term safety of its products…Where is the miracle of DDT now?… How big are current claims against the manufacturer of Roundup™? …What have neo-nicotinoids done to crop pollinators?…and so on.

It is charmingly naive to believe that there are magic bullets that will hurt our enemies but leave us undamaged. Toss into the mix that producing biocides is a fiercely commercial business and extreme caution is plainly needed before you even think of using them.

Woodstock, salt damage to the entrance to Blenheim Palace.

The same problem is visible all over Woodstock, and Woodstock is typical of villages and towns built with relatively soft oolitic limestone.

This image has several special points of interest:

  • The two stones forming the plinth appear to be relatively undamaged by salt crystallisation. This is deceptive. What it really means is that the salt damage was so bad at ground level and these two stones have been replaced relatively recently.
  • Immediately above the plinth stones, especially towards the right of the image, what appears to be stone is actually a loose pile of stone dust and salt crystals. For dust to build up in this way suggests that the current disintegration of the stone is extremely rapid.

 

Cultural significance...

Cultural significance: I’ll know it when I see it!

The following images try to show why cultural significance is so hard to define. A workable definition is important because we need to allocate scarce resource effectively. We need to decide why to conserve one thing and not another. Most commentators agree that the twin core attributes of cultural significance are age and rarity. There is much less agreement on any of the other possible attributes.

Stourhead

The Arcadian vision exemplified, complete with lake, bridge and temple all secreted in a private world hidden from reality.

. Ironbridge Museum, Tub Boat.

Probably the world’s first iron-hulled boat and thus a key part of the development of the industrial revolution. Not very Arcadian, very excluded (even by the museum that keeps it), and exceedingly difficult to conserve. If you want to understand the illogic with which we hand out cultural significance, compare this image of a revolutionary boat design with the useless decadence of the lead sculpture at Stourhead.

Channel Islands, German observation tower.

This is part of a class of buildings that have a particularly problematic claim to cultural significance. It is a product of the revolting and murderous Nazi regime, but because its narrative is deeply troubling, does that make it any less culturally significant and worthy of conservation?

Do I have a workable theory of how cultural significance can be determined? No. The more I try to attain one, the more doubtful I become of my own wisdom and everybody else’s. The only shred of certainty I have is that SPAB are right: we hold the buildings of the past in trust for the future without constructing rigid hierarchies of cultural significance.

Pastiche...

London, the V&A Museum, pastiche at its most ironic.

Ruskin, Morris and the SPAB have all inveighed against the evils of pastiche. So, what is it? You could say that Pugin’s slavish imitation of 13th century Early English architecture was pastiche. It borrowed the forms and materials of an earlier age and ignored the possibilities generated by the materials and demands of his own time…

But wait, what is the difference between pastiche and homage…hmmm, that’s a trickier one…

Nothing comes close to the irony, of reproducing a William Morris print on a plastic tea tray. Machine-made, mass-produced plastic tea trays symbolise everything that Morris detested… If the poor old Sunday socialist could see how the V&A have mangled his vision of craftsmanship, he’d be spinning in his grave faster than a gyroscope.

Optimism and the anvil of reality...

Trentishoe Church.

… A detail of the damage caused by salt crystals forming efflorescence on the surface of the gypsum plaster, expanding and pressing against the underside of the paint film. The emulsion paint here has proved well attached to the underlying gypsum plaster, but completely unable to accommodate the growth of the salt crystal behind it.

Bath, ceramic tube damp course.

Highly porous and permeable ceramic tubes inserted at regular intervals along the base of a damp wall are intended to intercept rising dampness and provide it with an easy evaporation route that diverts it away from delicate internal areas.

Do they work? This image suggests…not always. The white line in the upper part of the image is caused by soluble mineral salts crystallising. These salts and the moisture in which they are dissolved must be getting past the ceramic tube. Would they go higher if it were not for the ceramic tube? That’s a difficult question…

Hailes Abbey adhesive failure

The 1970s saw English Heritage experiment widely with epoxy and polyester adhesives. This stone fragment has been dowelled and resin fixed. When this photo was taken c.2001, no pressure was exerted to break the joint. Only gravity was holding the fragment in place, the resin bond having failed completely.

This failure at Hailes may or may not be typical. I don’t know because even if the medium-term performance of adhecive experiments has been monitored, the results have not been accessibly published. (See Corporate memory)

. Onehouse Church, resin grouting of the tower.

The tower was at serious risk of collapse (See Experiment, Materials, Stone and Resin) and was consolidated with resin grout. Whether this can be seen as a disciplined experiment is doubtful, and its success or failure is hard to judge. Most certainly the tower has not collapsed, but the money ran out during the ‘experiment’ and the grouting was never completed. Instead, approximately two metres of the tower was removed, and the battlements reinstated at a lower level. (See Grouting)

A very brief and highly defensive note was published by EH in response to hostile comment from SPAB and others, but there has never been a publicly accessible review of the ‘experiment’…

…You could not want for a better example of how corporate memory loss comes about…there is no deliberate policy of denying uncomfortable issues…there is simply silence until time and staff-change erase memories.

Since the separation of English Heritage from Historic England the corporate memory loss has become much worse. Staff cuts and endless reorganisations have removed almost all the senior staff who knew what had been done in the 1970s, 80s and 90s. There are written records, but to find the stories of sites like Steetley, Hailes or Onehouse, you first need to know that there is a story to be found.

Steetley Chapel. (See also: Consolidation ) A largely original Norman doorway carved in dolomitic limestone.

…English Heritage (as was) funded and promoted a disastrous experiment in silane conservation. The result was a rapid and extensive loss of historic material. This was bad enough, but the most serious part of the failure is that it has never been independently researched or published. Anyone visiting the site can see an obvious case of iatrogenic conservation, but Historic England has chosen to wipe the case from its corporate memory.

Fountains Abbey, ongoing stone erosion reveals evidence of grout.

The hard mortar visible in the centre of the image is grout rather than pointing. It is speculation, but is probable, that the grout has formed a water-resistant barrier and the diverted water is making the stone erosion problem worse.

Grout exposed by ongoing weathering is not limited to Fountains Abbey…

Tales of the unexplained...

Watchet Harbour, alveolar decay

The almost spherical nature of the alveoli does not have a definite explanation, but the most likely cause is wind blowing across the surface of the stone. This picks up loose grains of sand that have detached from the body of the stone and whirls them round like the pea in a pea whistle. I have observed this happening but whether my observation can be generalised to all alveolar decay is uncertain.