Returning to Milan, he made many designs for the Duke, and some for the masters of the Duomo of that city. The Church of S. Lorenzo had been begun in Florence at this time by order of the people of that quarter, who had made the Prior superintendent of that building. This person made profession of much knowledge in architecture, and was ever amusing himself therewith by way of pastime. And they had already begun the building by making piers of brick, when Giovanni di Bicci de' Medici, who had promised the people of that quarter and the Prior to have the sacristy and a chapel made at his own expense, invited Filippo one morning to dine with him, and after much discourse asked him what he thought of the beginning of S. Lorenzo. Filippo was constrained by the entreaties of Giovanni to say what he thought, and being compelled to speak the truth, he criticized it in many respects, as something designed by a person who had perchance more learning than experience of buildings of that sort. Whereupon Giovanni asked Filippo if something better and more beautiful could be made: to which Filippo replied, "Without a doubt, and I marvel that you, being the chief in the enterprise, do not devote a few thousand crowns to building a body of a church with all its parts worthy of the place and of so many noble owners of tombs, who, seeing it begun, will proceed with their chapels to the best of their power; above all, because there remains no memorial of us save walls, which bear testimony for hundreds and thousands of years to those who built them." Giovanni, encouraged by the words of Filippo, determined to build the sacristy and the principal chapel, together with the whole body of the church, although only seven families were willing to co-operate, since the others had not the means: these seven were the Rondinelli, Ginori, Dalla Stufa, Neroni, Ciai, Marignolli, Martelli, and Marco di Luca, and these chapels were to be made in the cross. The sacristy was the first part to be undertaken, and afterwards the church, little by little. The other chapels along the length of the church came to be granted afterwards, one by one, to other citizens of the quarter. The roofing of the sacristy was not finished when Giovanni de' Medici passed to the other life, leaving behind him his son Cosimo, who, having a greater spirit than his father and delighting in memorials, caused this one to be carried on. It was the first edifice that he erected, and he took so great delight therein that from that time onwards up to his death he was for ever building. Cosimo pressed this work forward with greater ardour, and while one part was being begun, he would have another finished. Looking on the work as a pastime, he was almost always there, and it was his solicitude that caused Filippo to finish the sacristy, and Donato to make the stucco-work, with the stone ornaments for those little doors and the doors of bronze. In the middle of the sacristy, where the priests don