Midway between these two systems--the system of the Greek sculptors and the system of Michelangelo--comes the system of Luca della Robbia and the other Tuscan sculptors of the fifteenth century, partaking both of the Allgemeinheit of the Greeks, their way of extracting certain select elements only of pure form and sacrificing all the rest, and the studied incompleteness of Michelangelo, relieving that sense of intensity, passion, energy, which might otherwise have stiffened into caricature. Like Michelangelo, these sculptors fill their works with intense and individualised expression. Their noblest works are the careful sepulchral portraits of particular persons--the monument of Conte Ugo in the Badía of Florence, of the youthful Medea Colleoni, with the wonderful, long throat, in the chapel on the cool north side of the Church of Santa Maria Maggiore at Bergamo-- monuments such as abound in the churches of Rome, inexhaustible in suggestions of repose, of a subdued Sabbatic joy, a kind of sacred grace and refinement. And these elements of tranquillity, of repose, they unite to an intense and individual expression by a system of conventionalism as skilful and subtle as that of the Greeks, repressing all such curves as indicate solid form, and throwing the whole into low relief. [70] The life of Luca, a life of labour and frugality, with no adventure and no excitement except what belongs to the trial of new artistic processes, the struggle with new artistic difficulties, the solution of purely artistic problems, fills the first seventy years of the fifteenth century. After producing many works in marble for the Duomo and the Campanile of Florence, which place him among the foremost masters of the sculpture of his age, he became desirous to realise the spirit and manner of that sculpture, in a humbler material, to unite its science, its exquisite and expressive system of low relief, to the homely art of pottery, to introduce those high qualities into common things, to adorn and cultivate daily household life. In this he is profoundly characteristic of the Florence of that century, of that in it which lay below its superficial vanity and caprice, a certain old-world modesty and seriousness and simplicity. People had not yet begun to think that what was good art for churches was not so good, or less fitted, for their own houses. Luca's new work was in plain white earthenware at first, a mere rough imitation of the costly, laboriously wrought marble, finished in a few hours. But on this humble path he found his way to a fresh success, to another artistic grace. The fame of the oriental pottery, with its strange, bright colours--colours of art, colours not to be attained in the natural stone--mingled with the tradition of the old Roman [71] pottery of the neighbourhood. The little red, coral-like jars of Arezzo, dug up in that district from time to time, are much prized. These colours haunted Luca's fancy. "He