Conservation of Reginald Marsh's WPA Murals
Painting Techniques
Reginald Marsh was well known for his technical expertise and eagerness to expand his knowledge. Having developed a fluent, gestural style as an illustrator, he was well suited to mural painting techniques, especially those requiring speed, such as fresco. Marsh set out to learn fresco painting with Olle Nordmark, a Norwegian fresco painter, for a commission at the Post Office Administration Building in Washington, DC. Working closely with Nordmark, Marsh was successful on his first attempt and completed two frescoes there.
Recognizing the architectural nature of the Rotunda panels at the U.S. Customs House and the appropriateness of painting on the plaster, Marsh eagerly set out to use his newly acquired skills. He believed that fresco would be most appropriate for the Rotunda, as it would allow the viewer to see the paintings at all angles without glare, while also being durable. Although the Secretary of the Treasury Relief Art Project, Olin Dows, had endorsed the use of fresco for many New Deal murals, he initially opposed Marsh’s proposal, believing that to remove and replace the plaster would be too expensive. But Marsh convinced Dows to allow him to proceed. Soon after Marsh began the long process of chipping away the old plaster, he realized that Dows was right. As a concession, Marsh completed the plaster work at his own expense.
Two wood scaffolds were built, with tiered platforms to conform to the curve of the dome and staircases to break the 50 foot climb to the base of the Rotunda, all while the Customs operations in the Rotunda continued. The scaffolds were moved along the walls as paintings were completed.
Marsh organized a team of eight to ten painters, including Nordmark and John Plochere, to complete the project. He worked long hours at their sides, sometimes as much as 14 hours a day. Once the plaster had been removed and the wire lath repaired, Marsh and his team applied a fresh plaster made of the traditional lime, fiber (in this case, coconut fiber) and sand. But unlike conventional fresco plaster, they fortified it with cement, an addition that would have strengthened the plaster but would also have accelerated the drying time. Documents indicate that Marsh and his team continuously wet the plaster in an attempt to retard curing.
Marsh came up with the ingenious method of transferring the drawings for the murals to the walls. He projected slides of pencil sketches of the murals on the Rotunda walls by means of a balopticon projector and outlined them in burnt sienna.
However, failed methods and materials and the addition of cement to the plaster ultimately made it impossible to complete the paintings in true fresco. Despite Marsh’s efforts to keep the plaster damp by spraying it, the lime had already begun to carbonate by the time he painted it. Instead of the buon fresco he planned to use, Marsh resorted to a secco painting technique. Documents indicate that he used skim milk as a binder.
Fresco Painting
Fresco painting is an ancient painting technique that requires the artist to apply pigments in water directly to wet lime-based plaster without the addition of a binding medium. This ancient painting technique utilizes the chemical transformation of the lime through three stages –from calcium oxide to calcium hydroxide to calcium carbonate - to integrate the pigments in the plaster such that they become part of its skin. Fresco technique was well chosen for the Customs House murals because of its architectural quality and durability. However, it demands that the painting occurs in a brief period of time when the lime has not yet begun to carbonate. It requires great speed of execution. Artists usually handle this brief period by applying only an area of plaster that can be painted in a day, called a giornata.
Successful execution of fresco requires considerable skill, as the artist must work quickly, capturing the moment between when plaster is firm enough to resist a brush and before the carbonate skin has begun to form. Because pigments are integrated with the carbonate layer of the lime plaster, fresco colors tend to be lighter, often pastel, and less dense than the saturated colors possible with oil or tempera painting. Accomplished fresco painters are able to achieve color density by repeated application of the pigment, by using a hatching technique, or, in rare cases, burnishing the surface. The fresco artist must limit his palette to pigments that are not altered by lime’s alkalinity, otherwise the pigments will alter and may even turn black.
Secco Painting
Secco painting refers to painting on dry plaster, as opposed to wet plaster. Secco paints include glue-bound paints, such as tempera, lime paints, and casein (milk allowed or caused to spoil and separating).
Throughout history, artists have combined fresco and secco painting as a way of extending beyond the limitations of curing plaster and to render detail, color density, and thickness. An artist may apply a fresco base and even complete entire passages affresco, while finishing the painting after the plaster has dried with pigments bound with egg, glue, or milk. Fresco painters have often fortified their pigments with lime milk, an approach that sometimes creates confusion that lime painting is fresco. However, if pigments are not applied before the plaster has carbonated, the painting is not a fresco, but rather a lime painting.
Current Conditions
It is unclear if the paintings were originally sound and resistant, but four campaigns of examination indicate that they have been in delicate condition for many years. As early as 1982, GSA was concerned enough to have a conservator examine them and report on their condition. The conservator found that the painted surfaces were extremely powdery, sensitive to touch, and that mildew showed evidence of water seepage from the skylight.
When GSA began the restoration of the fine arts at the Custom House in 1990, conservators were hired to examine the architectural finishes and mural paintings throughout the building and to help GSA to develop the scope of work in preparation for the actual conservation treatment. The conservators believed that the paintings were too fragile to clean and, at best, could be strengthened by carefully consolidating the most friable areas with ethulose, a cellulose adhesive.
In 1992 the actual conservation contract was awarded to two conservation firms, who worked on the contract cooperatively. As outlined in the scope of work, the conservators consolidated the 40% of the paintings that were most friable with the prescribed ethulose. Losses to the painting were compensated for with dry pigment in alcohol, without binding medium. The conservators concurred that the paintings could not be cleaned.
In September 2006, GSA once again returned to examine the condition of the paintings. The conservator on contract with GSA examined the paintings and carried out pilot testing over the course of ten days. Unlike his predecessors, he found that the paintings could be cleaned without damaging them by misting the surfaces with water and capturing the runoff water without surface contact. Following the cleaning, a consolidant would be applied in a similar manner to strengthen the paint and allow for future cleaning.
Examples of the cleaning tests can be seen on three of the murals in the Rotunda.
GSA is considering options for a phased conservation plan.
