Nothing preserves an arch like lime, milk and honey

Press, 7 December 1987, Page 40

Nothing preserves an arch like lime, milk and honey

By

BARRY MOODY

NZPA-Reuter

Rome After eight years of painstaking work, experts have almost completed restoring the ancient Roman arch of Septimius Severus — but they discovered many modern methods were more likely to destroy than save a monument. The magnificent triumphal arch in the ancient Roman forum was completed in AD 203 to celebrate the emperor Septimius Severus’ destruction of the Parthians after a 30-year war in part of what is modern Iran. The arch, using techniques developed by Rome’s military engineers, was built in two years by architects and craftsmen working around the clock. Even invisible parts are beautifully finished and the arch is covered with intricate sculpture. Lettering on top of the arch reveals an ancient crime. Septimius Severus’ son Caracalla had his brother Geta’s name erased and overwritten after he was murdered, but marks left by the original inscription can still be traced. The ravages of acid rain have destroyed more of the monument in a few

years than 17 centuries of wear and abuse, and survival of the arch was seriously threatened.

Before restoration work began in 1979, much of the marble had turned to plaster and many of the arch’s beautiful sculptures had literally been washed away. Roberto Nardi, the young Italian expert in charge of the restoration said much of the marble was like a plastic bag filled with sugar.

If the surface was broken, the marble inside would just crumble. He said 90 per cent of the original outer surface on the side facing the forum has disappeared. In many places, where there was once intricate sculpture of bearded warriors and battle scenes, there is now only smooth stone. Nardi’s team of 18 experts established that many preservation or restoration techniques irrevocably damage ancient monuments.

In the past, concrete and later resins were used to preserve ancient monuments, but they were harder than the original marble, causing cracks and decay. Nardi told reporters during a recent tour of the arch: “Restoration is a

two-edged sword. Done well it can save a monument, but this is rare. Done badly it destroys the rest of the monument and this is common. We therefore need to be cautious and go slowly." He was scathing about some notable mistakes in Rome, saying the Antonine Column, restored in 1956 with then fashionable resins and silicones, had been severely damaged.

“Now the monument is largely silicone surrounded by marble,” he said bitterly.

After what Nardi acknowledged as errors in the first three or four years of restoration, which required long periods of correction, his team decided that the only way to preserve the arch was to use the same natural “breathing” materials as the ancient Romans.

To repair everything from tiny cracks to big fissures the team has used various consistencies of filler and mortar made from water mixed with marble dust, volcanic rock, brick fragments and sand.

It was vital that the materials should be “self sacrificing” so that these declined rather than the

marble. The ancient Romans themselves helped to preserve the monument by frequent application of a liquid made from lime, sometimes mixed with milk and honey. This was so effective that where it remains, as a beige stain, the marks of original tools are still clearly visible. Nardi said modem substances tended to discolour in a matter of months or years in contrast to the 15 centuries or more of the original lime preserving liquid.

He said it was vital that this beige marking should not be removed because it continued to have a protective effect. Areas of the monument covered in a black crust were in fact better preserved than white sections exposed to rain. Here the water washed away not only dirt, but the marble itself after destruction, by acid rain from industrial and motor fumes.

The arch is so fragile that the restorers use a light spray of water droplets propelled by compressed air to loosen dirt before gently brushing the dirt off.

Nardi acknowledged the disappointment of tourists who for many

years have been coming to Rome only to find important monuments shrouded in green netting and scaffolding.

But he said this was the price to be paid for preservation because before work could begin a long period of study and cataloguing was necessary.

Over a period of six years the 3000 square metres of the arch were painstakingly drawn, photographed and computer recorded.

Once this process was complete, restoration moved rapidly with the restorers also recording their work in detail.

Nardi’s team has completed 90 per cent of the restoration of the west half of the arch. Now their funding, from the Italian Government, has run out so that the final 10 per cent will not be completed until next year.

The east side of the arch will take 12 months to restore but funding is unlikely to be available until 1989.

Meanwhile scaffolding and netting will continue to hide one of the marvels of ancient Rome from the eyes of frustrated tourists.