An hour before the wet dawn of Nov. 4, 1966, the swollen Arno River sent cataracts of water sluicing through the narrow streets of Florence and deposited half a million tons of mud, silt, rotting butchers' meat, excrement and sticky black fuel oil on the city's stone and stucco. At that moment, the future of the city and its artistic heritage seemed uncertain. The water was everywhere—soaking into the fragile wood of old carvings and panel paintings, expanding its cells and cracking it, seeping up inside walls and working outward through the surface of their frescoes, causing bloom, mold growth and discoloration, flaking the surface of porous stone like puff pastry.
Florence was confronted with the worst problems in the history of art conservation. But technology, as World War II showed, is stimulated by disaster. Today the art Restoration Laboratories in Florence's 16th century Fortezza da Basso have become the world's proving ground for conservation methods—thanks, in large part, to the collaboration of university laboratories and major chemical firms like Italy's Montedison. The techniques used by the more than 60 restorers and artisans in the Fortezza make most earlier methods look antediluvian. Says Umberto Baldini, 50, the dynamic head of the laboratories: "Once, restorers were like doctors who were trying to operate on a body without having done anatomical research. But the emergency of the flood made it obvious that art and science had to be brought closer together in a long-range program of research."
Baldini's allusion to medicine is more than casual. Even when the floodwaters had receded, hundreds of frescoed walls in Florence remained so damp that the paintings were threatened by a bacterial onslaught of molds and fungi. "If we had not found a solution," says Baldini, "those frescoes would have been devoured by micro-organisms." He and his colleagues ran through dozens of mold-killing antibiotics to test their effect on paint. Finally one was left: Squibb's Nystatin, a stomach medicine, which did not harm the pigments. But it came in the form of pills, which could not be fed to a wall. At last the University of Florence's chemistry department found a way to render powdered Nystatin soluble, and it was sprayed on the frescoes.
One spectacular result of this collaboration between art and science will be seen for the first time in seven years this summer. Like many other frescoes, Fra Angelico's Crucifixion, in the chapter house of the cloisters of San Marco (see color page), was suffering from a chronic problem that predated the flood: a pockmarked rash, resulting from crystallization within the plaster.