[40] By these "second gates" are of course meant Ghiberti's second gates: in reality the "third gates" of the Baptistery. The work took more than twenty-five years. The stories were all modelled in wax by 1440, when the casting of the bronze commenced; the whole was finished in 1447, gilded in 1452--the gilding has happily worn off from all the gates--and finally set up in June 1452, in the place where Ghiberti's other gate had been. Among his numerous assistants were again his stepfather Bartolo, his son Vittorio, and, among the less important, the painters Paolo Uccello and Benozzo Gozzoli. The result is a series of most magnificent pictures in bronze. Ghiberti worked upon his reliefs like a painter, and lavished all the newly-discovered scientific resources of the painter's art upon them. Whether legitimate sculpture or not, it is, beyond a doubt, one of the most beautiful things in the world. "I sought to understand," he says in his second commentary, that book which excited Vasari's scorn, "how forms strike upon the eye, and how the theoretic part of graphic and pictorial art should be managed. Working with the utmost diligence and care, I introduced into some of my compositions as many as a hundred figures, which I modelled upon different planes, so that those nearest the eye might appear larger, and those more remote smaller in proportion." It is a triumph of science wedded to the most exquisite sense of beauty. Each of the ten bas-reliefs contains several motives and an enormous number of these figures on different planes; which is, in a sense, going back from the simplicity of Andrea Pisano to glorify the old manner of Niccolò and Giovanni. In the first, the creation of man, the creation of woman, and the expulsion from Eden are seen; in the second, the sacrifice of Abel, in which the ploughing of Cain's oxen especially pleased Vasari; in the third, the story of Noah; in the fourth, the story of Abraham, a return to the theme in which Ghiberti had won his first laurels,--the three Angels appearing to Abraham have incomparable grace and loveliness, and the landscape in bronze is a marvel of skill. In the fifth and sixth, we have the stories of Jacob and Joseph, respectively; in the seventh and eighth, of Moses and Joshua; in the ninth and tenth, of David and Solomon. The latter is supposed to have been imitated by Raphael, in his famous fresco of the School of Athens in the Vatican. The architectural backgrounds--dream palaces endowed with permanent life in bronze--are as marvellous as the figures and landscapes. Hardly less beautiful are the minor ornaments that surround these masterpieces,--the wonderful decorative frieze of fruits and birds and beasts that frames the whole, the statuettes alternating with busts in the double border round the bas-reliefs. It is the ultimate perfection of decorative art. Among the statuettes a figure of Miriam, recalling an Angel of Angelico, is of peculiar loveliness.