Experts on the subject
The work of the restorers consists in re-injecting vitality into the statue décors on the rooftop, which lose their splendour due to bad weather and the passage of time. After a surface cleaning, the sculptures are scrubbed clean using the hydro-gumming technique (spraying the lead with a subtle mix of water, air and a low-pressure abrasive mineral), which gently removes any superficial oxidation and other impurities. Any cracks are then brushed clean and filled with lead that is then tamped down to ensure that it is perfectly waterproof (caulking). Lastly, the welding and final chisel-work bring out the well-defined reliefs. All these stages are necessary in order to gradually erase the damage caused by the weather. The work demands patience and a combination of strength and, at the same time, great precision. Restorers are meticulous and have an eye for detail: even a sculpted décor towering at a height of forty metres must be magnificent in its details. This talent for finely crafted work is acquired with practice and perseverance. It is then the task of the gilders to put the finishing touches to the final rendering by restoring the sublime splendour of the sculptures.