Schwarz paper outlined the extensive and complex treatment, carried out over four years, of 9 40 x 80” lunettes painted by Mowbray for Collis Huntington’s mansion in New York. After a thorough biography and outline of Mowbray’s artistic development, she moved into a description of the nine, brightly colored allegorical female muses depicted on the lunettes, which were originally adhered to Huntington’s walls with a thick layer of white lead paint.
In the 1920s when the mansion was demolished, the lunettes were removed from the walls (quite hastily) and given to Yale University Art Museum. Unfortunately they were rolled directly around stretcher bars and stored in a less than perfect environment, which, in combination with previous water damage and some mold, left the paintings in dire condition.
Technical analysis of the paint revealed other possible causes of paint loss. In his search for an absorbent yet flexible ground, Mowbray apparently added an aluminosilicate component (kaolin) to his ground layer, which has likely contributed to the current adhesion failure between the ground and paint layers.
One of the more interesting phenomena Schwarz discussed was the occurrence of bright orange fluorescence under UV radiation in some of the areas painted a mossy green color (but not everywhere). No varnish was present, and cross sections showed the fluorescence occuring only on the surface. SEM-EDS proved the paint layer to be a combination of viridian and cadmium, and Schwarz suggested that the fluorescence might be due to a reaction between cadmium sulfide and air, resulting in a cadmium sulfate. Apparently Aviva Burnstock has conducted research on this phenomenon at the Courtauld.
Questions following Scharz presentation focused on her strappo-inspired method of removing the lead white paint from the reverse of the canvases, which involved two layers of fabric strips and Beva 371 film. The paintings were lined onto aluminum honeycomb panels, to better mimic their originally presentation. The lining involved several layers, including a sacrificial layer to aid in reversing the lining. A nice diagram explained the lining stratigraphy, though I was not quick enough to note it. The paintings are currently on view in the galleries at Yale.