Conservation treatment of the wall painting

When the wall painting was removed from its original site, it was cut into eighty sections, backed with paper, and shipped to the museum (Fig. 4). The removal of the painting from its architectural situation initiated a series of decisions, within a Western paintings conservation tradition, as described here.

Figure 3

Infrared spectra from the Yuan dynasty wall painting (top to bottom): proteinaceous material in coarse render, resin in gilding mordant, wax associated with gilding, and PVAc from the 1930 restoration.

The painting was examined, treated, and reassembled by George Stout and Rutherford Gettens in 1930 at the Fogg Art Museum at Harvard University (Stout and Gettens 1930, 1931).6 A 5% solution of PVAc was sprayed on the front, and cracks and holes were filled with a mixture of clay, sand, and water; the surface was then brushed with a 20% solution of PVAc. The painting was faced with hide glue, paper, and muslin, and the back was scraped to a thickness of 1-2 mm. After the sections were lined with linen and treated with PVAc, they were held in a press for forty-eight hours7 and then glued to five wood panels for gallery installation. Finally, the facing was removed with water, and excess PVAc was reduced with toluene.

Figure 4

Sections of the wall painting in China, circa 1925.

PVAc was a new material to conservation in the 1930s. Gettens himself became aware of it through publications in 1928 (Gettens 1935:16). The long-term properties of PVAc as a surface consolidant were unknown, but it compared favorably with alternative contemporary resins. PVAc was colorless and retained the matte surface quality of an aged and untreated painting (Gettens 1935:19, 26, 27).

Since its treatment, the wall painting has remained stable with no cleavage from the wood support. The ornamentation is flattened, and the entire painting is smooth and hard. On close examination of the surface, residual PVAc is soft and visible with entrapped dust and dirt. The saw gaps between cut sections were integrated with a toned fill but were not inpainted.8 This choice, reflecting the collection history of the piece, remains the preference of the curator today. There are no plans at this time for additional conservation of the wall painting.