Il Cielo in una stanza. La volta prospettica di Canegrate (MI)

The architectural trompe-l’oeil that decorates the ceiling of the main room in the ground floor of Palazzo Castelli-Visconti di Modrone (in Canegrate, close to Milan) deserves full attention and is worth an accurate study. The author of the painting is known from the signature which is present at one corner of the ceiling: Gio. Batta. Grandi a fato la prospetiva (“Giovanni Battista Grandi did the perspective”), and we also know that the work was done around 1675. The illusionistic painting is thus contemporary to the first works by the more famous Jesuit artist Andrea Pozzo who was then living and working in Northern Italy, before moving to Rome in 1681. It therefore suggests that a school of quadratura existed in Lombardy in the second half of the seventeenth century, to which both Pozzo and Grandi most probably belonged. This study inquires both the Science and the Art of perspective painting and illusionistic quadratura. A thorough measured survey of the painting and the vaulted ceiling provided a reliable database on which to root the research. The study especially focuses on the practical aspects and difficulties that artists had to face and solve in order to actually paint in full size on the curved surfaces of the ceilings the virtual space that they had previously designed. The reading of Andrea Pozzo’s treatise, first published in 1693, helps to understand the tricks of the trade that were already in use in those years, but more has to be discovered about the various successive working phases that start with the preparatory drawing and ends with the final “rendering” of the painted architecture that transforms the room in a fake infinite space.