ITALIAN, FLORENTINE OR ROMAN WORKSHOP
GLOBE OF THE HEAVENS, GLOBE OF THE EARTH
Once barely legible because blackened and in precarious condition, the celestial globe-together with its companion, a terrestrial globe-recently was restored by Carlotta Beccaria, thanks to a contribution by Banca Intesa BCI. The rehabilitation of this object represents an important technical, artistic and scientific discovery.
The celestial globe, a one-of-a-kind piece destined for an elite audience, is characterized by its refined execution that uses oil pigments painted directly onto a gesso preparation differentiating it from the then common technique of gluing printed strips onto a sphere. The Ptolomaic constellations are depicted, such as the Big and Little Dippers (bears, in ancient occidental cosmology), Hercules, Cassiopia, Patera and Crater (the latter, represented by a beautiful cup). The names of the constellations are written in capital letters, while those of single stars are written in lower case. Along the line of the Zodiac, the representations of the signs are depicted. On the terrestrial globe, the relief of the mountains and waves is highlighted in gold, an attention to rendering detail that implies a patron of elevated taste. Xrays of the globes showed that the construction techniques used for the both the gesso spheres were identical. Both globes are hollow inside, and are supported by an iron bar that exits the sphere at the north and south poles. Pieces of wood are affixed internally with nails only to reinforce the structure at the entrance and exit areas of the pole.
The cleaning of the two globes was preceded by trials on two very small portions of the surface in order to determine the first phase focused on cleaning off the heavy layer of gray dirt and previous applications of turpentine, or glue. The surface of the terrestrial globe immediately was liberated from the heavy layer of atmospheric deposits, and reacquired a discreet legibility, while for the celestial globe it was necessary to treat some zones again because they were spotted with old varnish; the blue background–made up of a impasto of smaltino and a little bit of biacca, not adapted to oil painting–initially appeared very altered and grayed, but, in any event, it recovered a fine chromic intensity after the cleaning. At the end of the cleaning of the globes, they evidenced zones of patching, above all present in the cracks and in some areas of the background. The unnecessary patches were first softened then removed with scalpels, while the still useful, or well adhered, patches were retained. The painted surface did not evidence the need for a generalized consolidation, while there was a need to consolidate the color in particular places on the celestial globe. The painting was retouched by dotting varnish-based paints in order to reconstruct the chromatic panorama and to reduce the difference between the painted areas and the lacunae. At the end of the intervention, the spheres, replaced in their brass bases, were able to rotate perfectly freely without hitting on any part of the base.
Presumably acquired in the 1880s by the brothers, Fausto and Giuseppe Bagatti Valsecchi, for their Milanese home, the celestial globe, together with its companion piece, is displayed in the library, as the brothers originally intended it to be.