Now, not being yet satisfied with this beautiful invention--so lovely and so useful, above all for places where there is water, and where, because of damp or other reasons, there is no scope for paintings--Luca went on seeking further progress, and, instead of making the said works in clay simply white, he added the method of giving them colour, with incredible marvel and pleasure to all. Wherefore the Magnificent Piero di Cosimo de' Medici, one of the first to commission Luca to fashion coloured works in clay, caused him to execute the whole of the round vaulting of a study in the Palace--built, as it will be told, by his father Cosimo--with various things of fancy, and likewise the pavement, which was something singular and very useful for the summer. And seeing that this method was then very difficult, and that many precautions were necessary in the firing of the clay, it is certainly a marvel that Luca could execute these works with so great perfection that both the vaulting and the pavement appear to be made, not of many pieces, but of one only. The fame of these works spreading not only throughout Italy but throughout all Europe, there were so many who desired them that the merchants of Florence, keeping Luca, to his great profit, continually at this labour, sent them throughout the whole world. And because he could not supply the whole, he took his brothers, Ottaviano and Agostino, away from the chisel, and set them to work on these labours, wherein the three of them together gained much more than they had done up to then with the chisel, for the reason that, besides those of their works that were sent to France and Spain, they also wrought many things in Tuscany; and in particular, for the said Piero de' Medici, in the Church of S. Miniato al Monte, the vaulting of the marble chapel, which rests on four columns in the middle of the church, and which they divided most beautifully into octagons. But the most notable work of this kind that ever issued from their hands was the vaulting of the Chapel of S. Jacopo, where the Cardinal of Portugal is buried, in the same church. In this, although it has no salient angles, they made the four Evangelists in four medallions at the corners, and the Holy Spirit in a medallion in the middle of the vaulting, filling the other spaces with scales which follow the curve of the vaulting and diminish little by little till they reach the centre, insomuch that there is nothing better of that kind to be seen, nor anything built and put together with more diligence.