How do you clean a 2,000-year-old sarcophagus and get it ready for a road trip to Cleveland?
Very, very carefully.
Walters Art Museum conservators have spent the past three years restoring a 500-pound, child-size coffin, elaborately carved with winged goddesses, Medusa heads, the masks of comedy and tragedy, and the offerings of fruit and flowers left as tributes to the dead.
The conservators have used an instrument resembling a space-age-style ray gun to detect lingering traces of red paint that has lasted for nearly two millennia — an accomplishment that seemingly eludes the manufacturers of modern-day wall-colorings.
The restoration experts have cautiously dissolved the 19th-century glue that held together the 15 separate pieces that make up the lid of the so-called Garland Sarcophagus, and crossed their fingers that when they did, the marble lid wouldn't crumble into a pile of dust.
Once the sarcophagus is ready to hit the road, so to speak, it will be hoisted into the air on pulleys and then lowered into two custom-designed crates: one for the rectangular bottom part of the coffin and the second for the peaked lid.
"I approach each piece as if it were made of nitroglycerin," says Michael McKee, the Walters' senior collections technician, who is in charge of ensuring that the marble treasure remains intact during its 373-mile, pothole-strewn journey. "Slow and methodical is the key. I pretend that at any moment it could explode, so I have to move it as gently as possible."
Once the conservators finish up this summer, the sarcophagus will hitch a temperature-regulated and humidity-controlled ride to the Cleveland Museum of Art as part of an exhibit opening Oct. 17. The show, called "Treasures of Heaven: Relics, Saints and Devotion in Medieval Europe," then sets up in Baltimore and will be displayed in the Walters from Feb. 13 to May 15, 2011.
"Sometimes when we're working, the piece will look worse before it looks better," says Julie Lauffenburger, the Walters' senior objects conservator. "That's really frightening."
Against all odds, the sarcophagus has remained more or less intact since the peak of the Roman empire, when the original marble slap was hauled all the way to Italy from a quarry in Phrygia, a region of present-day Turkey.
It would be a pity if something were to happen to it now.
"There are so many things that can go wrong," Lauffenburger says. "It's a big responsibility."
Though much about the sarcophagus remains hidden and mysterious, the bits that the Walters staff have pieced together are intriguing. For instance, the coffin most likely was carved for a child from a wealthy family.
According to written materials prepared for the exhibition by the museum's curators, there are hints that the beautiful casket was something of a rush job. There are incomplete areas on all four faces, suggesting that the work was interrupted midway through — perhaps indicating that the sarcophagus was needed more quickly than the child's family had anticipated.
The material notes "that it is often impossible to know the reason" a casket was left unfinished. But in ancient Rome, the burial ceremony didn't necessarily mean saying goodbye. It was traditional for the deceased to continue to be part of the family.
"Roman tombs often housed the remains of several generations," the text reads. "They could be visited by family members, who would hold ceremonial meals and perform other rituals in the tombs at certain times of the year."
The show's curators were interested in the Garland Sarcophagus because it represents a link between the pagan cult of the dead and such Christian traditions as saints, whose powers are thought to extend beyond the grave.
"Both are based on the idea that the dead person is not really dead," Martina Bagnoli, who heads the Walters' department of medieval art, writes in an e-mail. "In particular, we wanted to explore the pagan concept of communing with the dead, and how that became important for the Christian cult of the saints."
The lid of the Garland Sarcophagus resembles a gabled roof. Similar architectural shapes later appear in reliquaries — the bejeweled containers for such sacred Christian objects as the bones of holy martyrs.
In addition, the sarcophagus is notable for its design of fruits and flowers, which represents the gifts to the dead that visitors frequently left at the tomb.
But by the time the marble casket became part of museum founder Henry Walters' collection in 1902, it was a mess.
The sarcophagus was one of seven that were unearthed in 1885, when piles were being driven for a new apartment building in Rome. The lid of the Garland Sarcophagus was in several pieces, indicating that it had been pilfered by grave robbers searching for treasure.
In the 108 years that the sarcophagus has belonged to the Walters, it had never been cleaned. When the restoration is completed, all four faces will be on view for the first time.
"Cleaning the sarcophagus is the most irreversible part of the process," says Jessica Arista, an intern in the Walters' conservation department. "If you take something off that shouldn't have come off, you can't put it back on."
She and the other interns put in most of the 400 hours that have gone into rejuvenating the piece. The team went over the sarcophagus centimeter by centimeter, using a cleaning system based on distilled water because it contains fewer minerals. They used the "ray gun" —a machine that records the presence of trace minerals present in paint — to warn them where to proceed with extra caution to avoid dissolving lingering bits of gilt..
Then the conservators went to work with a scalpel.
"A major part of the treatment," Lauffenburger says, "is removing materials that were used previously in an attempt to restore it."
Conservators from the 19th century did the best they could. They glued the broken lid back together and plastered over the holes, occasionally obscuring the original carvings. Over time, the glue lines darkened to a brownish-yellow and stood out in sharp contrast to the more delicately colored marble.
Bit by bit, the interns chiseled away the old, brittle glue and plaster, exposing a network of cracks and chips. They then filled the chips with a new kind of glue, one that is fully reversible and mimics the texture of the rough stone surface.
"At first, we tried adding ground marble," Arista says, "but paper worked better. It looks more like marble."
Now the conservation project is in its final stage.
Arista, her hands swathed in blue plastic gloves to prevent her from inadvertently touching the piece with human, oily hands, works away at an area on the lid with a brush no wider than a penstroke. She dips the tip of her brush alternately in charcoal, brick red and chocolate, using a dabbing motion reminiscent of such pointillist painters as Georges Seurat.
"This is bigger than the brush I usually use," she says, adding that the patch being painted, perhaps 4 inches long and 2 inches wide, will take about 10 hours to complete.
"Sometimes, I do get in the groove, and then I have to stop myself from working too quickly," she says.
To a certain extent, it will be Arista's handiwork on display once the sarcophagus is finished. Her brushstrokes, her plaster carvings will replicate the cuts made in marble by the unknown master — or masters — who lived 20 centuries ago.
'You'll always be able to see the cracks up close," she says. "You should be able to see them. But if we've done our job right, when you're in the gallery and standing back a couple of feet and the lights are low, your eyes will just move past that area. You'll see the object as it was originally meant to be seen."