Among the first to give Luca commissions for this exquisite work in clay was Piero de' Medici. For him Luca decorated a small book-lined chamber in the great Medici palace that Cosimo had built. His work was for the ceiling and the pavement, the ceiling being a half sphere. For the hot summer days of Italy, when the streets are a blaze of light and the sun seems to embrace the city, this terra-cotta work with its cool whites and blues, was particularly delightful bringing really, as it were, something of the cool morning sea, the soft sky, into a place confined and shut in, so that where they were, coolness and temperance might find a safe retreat. And it was in such work as this that he found his fame. Andrea della Robbia, his nephew, the best artist of his school, follows him, and after come a host of artists, some little better than craftsmen, who add colour to colour, till Luca's blue and white has been almost lost amid the greens and yellows and reds which at last altogether spoil the simplicity and beauty of what was really as delicate as a flower peeping out from the shadow into the sun and the rain. But of one of the pupils of Luca, Agostino di Duccio, 1418-81(?), something more remains than these fragile and yet hardy works in terra-cotta. He has carved in marble with something of Luca's gentleness at Perugia and Rimini. He left Florence, it is said, in 1446, after an accusation of theft, returning there to carve the lovely tabernacle of the Ognissanti. It is said that he had tried unsuccessfully to deal with that block of marble which stood in the Loggia dei Lanzi, and from which Michelangelo unfolded the David. Two panels attributed to him remain in the Bargello, a Crucifixion and a Pieta, which scarcely do him justice. The last sculptor of the first half of the fifteenth century, his best work seems to me to be at Rimini, where he worked for Sigismondo Malatesta in the temple Alberti had built in that fierce old city by the sea.