Historic Churches 2020

BCD SPECIAL REPORT ON HISTORIC CHURCHES 27 TH ANNUAL EDITION 23 size and shape of the gilded haloes demonstrate a high level of skill, as well as a fairly diverse palette and pattern range. Once the varnish was removed, details became visible that had previously been completely obscured, such as delicate facial features, attributes and drapery designs. In the chancel, the alkaline cleaning agent was again found to be most effective at varnish reduction. In order to mobilise the varnish in the pitted plaster surface, it was found that applying the material as a gel and using brushes to agitate the solution was the most effective. As with the nave, treatments were timed but mainly depended on the skill and sensitivity of the conservator to determine how long to leave the cleaning agent on the surface, or whether a second application was safe. While the painted wood of the nave was relatively smooth and permitted swabbing, the pitted texture of the chancel meant that achieving an even clean overall became quite challenging, so the decision was made to reduce rather than remove varnish from the chancel ceiling. As a result, instead of returning the ceiling painting to its original aesthetic (vibrant reds, blues and greens above an off-white background), the ceiling retains an element of the yellow colour imbued by the deteriorating varnish. Nevertheless, the lightening of the yellow- brown varnish was dramatic, allowing colours that had been hidden for many years to re-emerge, and the legibility of the entire scheme was much improved. The decision to retain its non-original yellow appearance does raise ethical considerations concerning the extent to which a conservation treatment should affect the original intention of the artist. Another consequence of the decision not to wholly remove the varnish was a white bloom that developed following the cleaning treatment. After analysing a sample of the paint layer, it was confirmed that the bloom was caused by moisture trapped in the remaining varnish as it re-hardened after the cleaning process. Conservators developed a method which involved brushing the edges of an area after cleaning to ‘feather’ the remaining varnish, as well as targeting problematic areas with a re-application of the cleaning agent to further reduce the varnish. Retouching missing paint layers For both ceilings retouching was kept to a minimum due in part to the fact that small areas of loss are not visible from the ground. Where loss was substantial and would hinder legibility or be distracting to the viewer, existing details were emphasised and lines continued where the design was certain. Reversible watercolour paints were used for this, sometimes with the addition of ox gall, a wetting agent, to improve adhesion of the paint. The most significant area of retouching was on the figure of St Matthew, which had sustained severe damage and loss during earlier interventions. Care was taken not to ‘invent’ any part of the composition; the saint was re-created using existing lines, matching the tone and colour of its features, such as the hair, to tone down losses. Retouching was also necessary along the ribs towards the west end of the nave, due to more aggressive cleaning in this area historically. Watercolours were again used for the painted sections, while mica was added to Regalrez 1094 synthetic varnish to tone down losses to the gilded decoration. Stabilisation In addition to varnish removal other conservation treatments were undertaken. In the nave, the edges of the marouflage paintings that had separated from the St Matthew before retouching (Photo, left: Cliveden Conservation) and afterwards (Photo, right: Anthony Coleman): restoration was possible because the lines of the original could be discerned clearly. A gilded boss in the chancel during cleaning to remove the yellowed varnish (Photo: Cliveden Conservation)