sentences:  Under Brunelleschi's supervision he managed to lay the foundations, raise the main walls, finish off the basement with a cryptoporticus beneath the cloister walks, and the lower part of the front facing loggia.Later phases added the attic story (1439), but omitted the pilasters that Brunelleschi seems to have envisioned, and expanded the building by one bay to the south (1430).Colored terracotta medallions by Andrea della Robbia can be seen in the spandrels of the arches, the so-called "Infants", which were put up in 1485.