Eye on Preservation

The window's side sections depict Freemasons traveling to California, while the center features Masonic symbols. Steel-framed panels, 45 in total, occupy a 38-by-48-foot expanse along the south wall of the marble-clad building by Albert Roller.

The all-seeing eye, symbol of the supreme being, has gazed down from a large window in the foyer of San Francisco's California Masonic Memorial Temple for half a century now. When daylight shines through the colorful Masonic symbols and depictions of Freemasons traveling to California, most people assume that the window is stained glass. Actually, the mosaic contains not only glass but also acrylic, shells, metal, fabric, and earth, all sandwiched between panels of plastic. Yes, plastic.

A California artist named Emile Norman began experimenting with what he called "endomosaics" in the 1950's, and his largest, at 38 by 48 feet, is the one at the temple—a modernist white marble-clad building completed in 1958. To make each panel, Norman used polybutylene, a clear adhesive, to stick the tesserae to a sheet of methyl methacrylate. He then placed another sheet on top and set the panel in a frame, ready for installation on the temple's south-facing wall. After five decades of exposure to the elements, however, some panels had deteriorated. Things came to a head when bits of the blue iris of the all-seeing eye started falling out.

Conservators at Architectural Resources Group set up a workshop in the temple's underground garage to repair cracks, re-glue separated panels and fallen tesserae with fresh polybutylene, and clean areas discolored by dirt and moisture. Replacing cork gaskets with neoprene ones would allow the panels to expand and contract with temperature changes. The final step was to replace the original protective screen on the exterior with a new, UV-resistant version that filters 100 percent of the sun's rays.

"Plastic came of age as a design material in the 1950's," principal David Wessel says. "Conservation is relatively new." Fortunately, he was able to meet early in the process with Norman himself—now in his 90s and living in Big Sur—to get his permission and help. It turns out that the Masons had the foresight to ask the artist to write down the mural's materials and construction methods, seal them in an envelope, and file it away in the center's safe.