Brunescelli and Michelozzo

This study is devoted to the double-bay Chapel of Cosmas and Damian in San Lorenzo, Florence, which despite its Medici patronage has attracted few scholarly interest, and its relationship with the neighboring Old Sacristy. It aims to demonstrate that the chapel was begun later than the sacristy and built in two stages: Filippo Brunelleschi, who had designed the new transept of San Lorenzo on commission from Giovanni de’ Medici, was involved only with the first stage. After he had built the external walls and begun the one towards the interior of the church, around 1428 Giovanni’s son Cosimo took over, bringing in his favored architect Michelozzo di Bartolomeo. He must have been responsible for the demolition of the unfinished internal wall and the adaption of its pilaster and pier into an entrance to the chapel’s inner chamber. With its tympanum featuring a scallop shell, the portal is identical in appearance to the one Michelozzo built contemporaneously at the sacristy entrance, thereby creating a symmetrical façade that unites the chapel and the sacristy into a Medici spiritual compound. It is argued here that this type of scallop shell was alien to Brunelleschi’s architectural language and that its introduction in the lantern of the cathedral was due to Michelozzo as well; in San Lorenzo it must have been chosen also for its funeral symbolism, in a space that was to contain the tombs of both Giovanni and Cosimo de’ Medici. Moreover, this article analyzes the reasons for the awkward placement of the entrance to the Old Sacristy, which cuts off the folded angular pilaster. It maintains that Brunelleschi’s entrance must have been contained within the thickness of the wall and that only the wooden door installed in the 1450s forced its enlargement, thereby damaging the sacristy’s carefully thought-out architectural system.