National Geographic : 1972 Nov
Dulled by time, Tintoretto's 400 year-old masterpiece "The Ascen sion" revives under the restorer's touch. Professor Antonio Lazzarin has replaced the backing and cleaned the oil-painted surface. Now he retouches areas of missing paint on the figure of Christ. Grimed by "progress," a 15th century marble lunette gets a beauty treatment. Protected by masks, Kenneth Hempel and an assistant clean the Virgin and Child at the basilica of the Frari. A specialist from London's Victoria and Albert Museum, he aims a high-speed stream of dust-fine glass beads to blast away the dark encrustations.