By Jeffrey Levin

At about an hour past midnight on an October night in 1932, Arthur Millier, art critic for the Los Angeles Times, wandered through Olvera Street in downtown Los Angeles. There he found Mexican artist David Alfaro Siqueiros, sitting on a scaffold, "sweating in an undershirt" and "painting for dear life."

Siqueiros was struggling to finish his largest work since he had arrived in the city earlier in the year. It was a 24-by-5.48-meter (80-by-18-foot) mural, situated on the outside second-story wall of Olvera Street's Italian Hall.

Color rendering prepared by conservator Agustín Espinosa in 1990, showing how the mural might have looked when first unveiled.

The mural had been commissioned by gallery owner F. K. Ferencz of the Plaza Art Center, who instructed that its theme be "tropical America." Siqueiros—a participant in the Mexican Revolution and a seasoned Communist Party organizer who had just spent a year in Mexican prison for his activities—had no intention, he later said, of painting "a continent of happy men, surrounded by palms and parrots, where the fruit voluntarily detached itself to fall into the mouths of the happy mortals."

However, for most of the weeks that Siqueiros and his team of assistants labored on the mural, the work's central image remained unpainted and the artist's ultimate intent unclear. Then, as Millier reports, the day before the scheduled unveiling, Siqueiros sent everyone home and worked through the night to complete the mural's main figure. Set in front of a Maya-like pyramid, he was an Indian crucified on a double cross with an American eagle above him. In the upper right-hand corner of the mural, two revolutionary soldiers were depicted, one pointing his rifle at the eagle.

The work was unveiled October 9, 1932. When the scaffolding came down, "onlookers gasped," reported Millier in the Times. "No one but the author had been able to visualize the close-knit powerful design so long shaded and concealed by those scaffolds."

For a number of the city's artists, including those who had assisted Siqueiros with the mural, the work was tremendously exciting. "It had guts in it," recalled one over 40 years later. "It made everything else at the time look like candy box illustrations. Many of the artists said, 'My God! This is wonderful vocabulary.'"

Such enthusiasm was not universal. While acknowledging the mural as "an interesting experiment," one review asked "Why get hysterical about Mexican art?...Why imitate it and adopt it in our own country, whose traditions are entirely alien to it all?" The reviewer pleaded to "keep the Mexican motif in the Mexican quarter."

The negative reaction did not end with criticism of the mural's aesthetic aspects. Its political content prompted outrage from some of the city's civic leaders, including those who had established Olvera Street as a Mexican marketplace two years earlier. Not long after the mural's completion, Ferencz was forced to cover over the most visible third with white paint. Within a year, the entire mural was painted over.

The controversy did little for Siqueiros' political standing in the United States. A renewal of his six-month visa was refused, and he was forced to leave the country. But the episode by no means brought a halt to Siqueiros' career. His stature as an artist continued to grow, and today he is known as one of the triumvirate of Mexican muralists, along with Diego Rivera and José Clemente Orozco, who reawakened the world to the dynamic possibilities of mural art.

As for América Tropical—as the mural is now known—it was forgotten for decades, left to languish in the strong Southern California sun. In the early 1970s, the first efforts to preserve the now-fading masterpiece began, but it wasn't until the late 1980s that, with the assistance of the Getty Conservation Institute, substantial steps were taken to save the only surviving public mural by Siqueiros in the United States.

The Neglected Masterpiece

The techniques and materials employed in the creation of América Tropical Siqueiros first tried out several weeks earlier in a fresco class he taught at Chouinard Art School. Over a two-week period, he and his students painted upon one of the school's walls an outdoor mural called Street Meeting. (This mural, too, was an object of controversy and ultimately covered over.) In preparation for the mural, a pneumatic drill was used to roughen the wall surface and give greater adhesion to the white cement on which the mural was painted. Because the cement dried rapidly, Siqueiros used an airbrush extensively in applying paint.

A similar approach was utilized in the making of América Tropical. "From here," Siqueiros later said of his experimentation on the mural, "all my methods changed on the road to a modern technology for social modern art."

The artist no doubt hoped that the experimental methodology would prove durable. Indeed, one contemporary review of the mural concluded that "rains will never wash it off, nor sun dim its details, for it is cement!"

Time did not confirm this appraisal. In the decades that followed its creation and covering over, the mural displayed the effects of sun, rain, smog, and earthquakes. The painting layer beneath the white paint began to deteriorate as the white paint itself slowly eroded. In places the mural faded and peeled. Portions of the plaster started detaching from the wall. Due to the high level of pollution in the area, the mural's surface became coated in dirt.

Siqueiros in 1971. Photo: Luis Garza.

In the early 1970s, art historian Dr. Shifra Goldman and Los Angeles filmmaker Jesús Salvador Treviño spearheaded the first attempts to preserve the mural. Stimulated by their efforts, Siqueiros himself made plans to paint a replica of the central portion of the mural on a series of wooden panels, which he intended to present to the city of Los Angeles. Unfortunately, the artist died in January 1974, before the panels were completed.

In 1977 Jean Bruce Poole joined the staff of El Pueblo Park, the city agency that today administers the historic block of buildings on Olvera Street. As the park's senior curator, Ms. Poole was surprised to learn of the mural's existence. "I said, 'Look, you've got a masterpiece here. It's an absolute outrage; you've got to do something to save it.'" Joining forces with others already working for the mural's preservation, she sought technical assistance and resources to save what remained. But despite a growing interest in the mural by the city's Mexican-American community, financial support for its conservation did not materialize. Because of the lack of funds, no preservation measures were taken other than erecting a protective plywood shed around the mural.

The 1990 cleaning and consolidation of the paint layer during the first phase of the conservation program. Photo by Nancy Kaye.

In 1987 Ms. Poole met with then-Getty Conservation Institute Director Luis Monreal and Special Projects Director—now Institute Director—Miguel Angel Corzo, to discuss América Tropical. Mr. Corzo, a native of Mexico City who grew up seeing the murals of Siqueiros, Rivera, and Orozco, had viewed América Tropical for the first time just a few months earlier. "I was really appalled that nothing had been done to conserve it," he recalled. "There seemed to be no sense of respect for the work of art, which was very saddening." Because of the mural's aesthetic and symbolic value, he felt strongly that the Institute should get involved.

Later that year, David Scott and Michael Schilling of the Institute's Scientific Program took paint samples from the site and prepared an analysis of the paint pigments used in the mural. Subsequent analysis of a sample removed from the site in 1971 indicated that the paint's binder was probably cellulose nitrate. The exposure to direct sunlight and pollution of a binder consisting of cellulose nitrate, over a period of many years, would significantly contribute to the deterioration of the mural's painting layer.

In 1988 the Institute officially joined with El Pueblo Park and the Friends of the Arts of Mexico Foundation to undertake the mural's rescue. After consultation with conservators and engineers, a comprehensive program for saving América Tropical was developed.

The Conservation Effort

The first phase of the mural's conservation began in 1990. Mexican conservators Agustín and Cecilia Espinosa headed the conservation team, assisted by two students from the wall paintings conservation training program of the Courtauld Institute of Art in London. Over the course of several months, the team removed the remaining white paint from the mural, cleaned and consolidated the painting layer, and reattached loosened cement plaster to the brick wall. Traces of asphalt running along the base of the painting were also eliminated.

Photo taken in 1932 showing whitewash covering the most visible third of the mural. Photo courtesy of El Pueblo de los Angeles Historic Park.

In May 1991 the Institute installed an environmental monitoring station adjacent to the mural. For over a year and a half, the station measured such factors as wind speed and direction, rainfall, temperature, humidity, and the movement of sunlight across the mural's surface. The data collected provided valuable information about environmental conditions at the mural to assist in the designing of a protective shelter by Altoon & Porter, a leading Los Angeles architectural firm with experience working on historic structures.

In the spring of 1994, the Institute took another step in its comprehensive assessment of the mural's condition. With equipment designed by Eric Lange, a Fellow at the Institute, the entire mural was documented using digital imaging.

From the beginning of the preservation program, public access to the mural has been a primary objective. An estimated 1.5 million people come to Olvera Street annually. Many would undoubtedly make the mural part of their visit if access were provided. At the same time, because of its artistic and historic importance—and its significance to the city's large Mexican-American population—América Tropical has the potential to draw new visitors of its own.

Several major steps remain before public access can be achieved. The first is the seismic stabilization of the Italian Hall and adjacent buildings. This work is scheduled to be started this year.

In addition, plans are being developed for a permanent mural shelter, a public viewing platform, and a historical information area that can provide visitors with a context for viewing the mural. The Institute, together with other organizations, will reach out to the public and private sectors to underwrite the cost of constructing the mural shelter and the public areas. Once a shelter is installed, the mural's final cleaning, stabilization, and consolidation can proceed.

This last effort will not, unfortunately, return América Tropical to its original glory. The problematic nature of the materials used in its creation, combined with years of deplorable civic neglect, have left the Siqueiros masterpiece a shadow of its original incarnation. Much of its color is gone.

Nevertheless, the artistic power of the work remains. "You've only got to look at that mural to see the strength in the painting," says Jean Bruce Poole. "Even faded, it is still immensely strong."

Ms. Poole, now director of El Pueblo's Historic Museum, believes that even in its present condition, the mural is "telling a story," one of political controversy and artistic expression. "The mural is tremendously important because it's part of the city's history," she explains. "Even the fact that it's been so badly treated is part of the history."

Luis Garza, the Institute's consultant coordinator for the mural project, agrees. "América Tropical has come to epitomize the historical mistreatment of art," he says. Seeing the mural as it is today vividly demonstrates what is lost by such mistreatment. Its destruction by civic leaders provides a contemporary lesson in the consequences of intolerance.

However, as he also points out, the mural is much more than a symbol of artistic censorship and prejudice. América Tropical profoundly influenced the mural movement so interwoven into today's Los Angeles, a city with over fifteen hundred public murals. Its legacy in public art, despite its treatment, is considerable.

The conservation of the mural and its return to public view, Mr. Garza believes, can help heal divisions within the community. "The political and social issues the mural so dramatically depicts engage all of us," he observes. "The process of conserving América Tropical gives those in our community that rare opportunity to get to know one another better."

This, as much as anything, forms the basis for the Getty Conservation Institute's involvement in the project. As Harold Williams, President of the Getty Trust, has declared, the Trust's long-term goals in its home community include "creating an urban environment in which diversity is a source of strength rather than of conflict."

After over sixty years of existence, América Tropical today transcends the controversy that accompanied its birth. "It's a universal work of art," says Miguel Angel Corzo. "It represents a social struggle which we all can understand now. It's a mural for the whole city."

Mural Update

For 16 straight days in April, América Tropical was once more the site of intense activity. Again scaffolding went up, but the effort on this occasion was not mural creating but recording. Using the Siqueiros mural as a first field site, a small team of Getty Conservation Institute staff, led by Eric Lange, a British conservator and GCI Research Fellow, tested a new system for direct digital capture of a wall painting in situ.

In contrast to conventional photography, digital image capture utilizes a specially designed computerized camera back to record images directly onto a computer hard drive or optical disk. Thus, although the image can be viewed, manipulated, and output as if it were a photographic image, the information is actually recorded and stored as a block of binary code (i.e., a series of 1's and 0's), rather than as a "picture" on film.

Digital imaging of wall paintings in the field offers a number of advantages over traditional methods. While on site, conservators can record cracking patterns, plaster joins, previous restorations, biological deterioration, and other important features using a program such as Adobe Photoshop to produce color-coded transparent "overlays" directly on the images. These layers can be viewed individually or in combination, and can be turned on or off at the touch of a button. Another advantage of digital capture is that it allows the conservator to instantly magnify or enhance particular areas or features of interest.

"What we set out to do was to see if digital capture could be done on-site by conservators in a way that was feasible and practicable," says Mr. Lange, who researched and designed the digital documentation system and organized this test at América Tropical. The commercially available components of the system included a Hasselblad camera with a Zeiss lens and Leaf digital camera back, and a Quadra 950 computer with extended ram and a 20-inch color monitor. Custom components included special scaffolding that moved on a self-leveling trackway, and a camera dolley that rode on its own track at the top of the scaffolding. This system allowed for the camera to be positioned with considerable accuracy.

Hasselblad camera, Leaf digital camera back, and custom-built filter wheel mounted on a special camera dolley for accurate positioning. Photo: E. Lange.

One hundred fifty-six images were captured in a grid 6 images high by 26 images wide. Once the on-site recording phase was completed, lower resolution copies of the original (12.6 Mb) files were "mosaiced" together to create a single image of the mural. Since the painting is covered by a very narrow shelter, it is impossible to view the site in its entirety, and until now no single image of the mural in its current state existed. Without the capability for digital calibration and adjustment of illumination, color balance, and registration as each shot was captured, it would have been extremely difficult to achieve sufficient consistency with film photography to produce a seamless composite of 156 images.

The precision of digital photography has another important advantage: Since the information is actually recorded in a numeric rather than photochemical way, it establishes a baseline to which future recordings can be compared to provide accurate and quantifiable analyses of change. Similar comparisons could be made using images in the ultraviolet, infrared, and thermographic spectra.

Traditional methods of site documentation often produce large quantities of information in a variety of formats: binders of slides and photographic prints, oversized files of drawings and transparent overlays, field logbooks, etc. "In terms of information management," says Mr. Lange, "digital documentation can provide immediate, on-site integration of all images, diagrams, condition reports, treatment notes, and other materials generated in the field—all of which can be stored on a few magneto-optical disks. Furthermore, this information is more accurate, more accessible, and easier to reproduce than that generated by traditional techniques."

Jeffrey Levin is the editor of Conservation, The GCI Newsletter.