Restoration of The Sistine Chapel Frescoes - Previous Restorations

Previous Restorations

The frescoes on the ceiling of the Sistine Chapel had a number of interventions prior to the restoration process which was started in 1980. Initial problems with the ceiling appear to have been caused by water penetrating through the floor above. In about 1547 Paolo Giovio wrote that the ceiling was being damaged by saltpetre and cracks. The effect of saltpetre is to leave a white efflorescence. Gianluigi Colalucci, Head Restorer at the Laboratory for the Restoration of Paintings for Papal Monuments, Museums and Galleries, states in his essay Michelangelo's colours rediscovered, that the early conservators treated this cosmetically by an application of linseed or walnut oil which had the effect of making the crystalline deposit more transparent.

In 1625, a restoration was carried out by Simone Lagi, the "resident gilder", who wiped the ceiling with linen cloths and cleaned it by rubbing it with bread. He occasionally resorted to wetting the bread to remove the more stubborn accretions. His report states that the frescoes "were returned to their previous beauty without receiving any harm". Colalucci states that Lagi "almost certainly" applied layers of glue-varnish to revive the colours but does not state this in his report in the interests of "preserving the secrets of their craft".

Between 1710 and 1713 a further restoration was carried out by the painter Annibale Mazzuoli and his son. They used sponges dipped in Greek wine which Colalucci suggests was necessitated by the accretion of grime caused by soot and dirt trapped in the oily deposits of the previous restoration. Mazzuoli then worked over the ceiling, according to Colalucci, strengthening the contrasts by overpainting details. They also repainted some areas the colours of which were lost because of the efflorescence of salts. Areas of repainting were hatched or treated with a linear brushstroke. Colalucci states that Mazzuoli also applied a great deal of glue varnish. The restoration concentrated on the ceiling and less attention was paid to the lunettes.

The penultimate restoration was undertaken by the Restoration Laboratory of the Vatican Museum between 1935–38. The scope of the work was to consolidate some areas of the intonaco at the eastern end of the building and partially remove the soot and dirt.