Until 1475, Neroccio was in partnership with one whose ambition went far to destroy what Neroccio and Siena stood for. Francesco di Giorgio was born in 1439. With an ambition and resolution wholly un-Sienese, he mastered the arts of painting, sculpture, architecture and engineering. He met Leonardo da Vinci at Pavia, worked for the tyrants of Milan, competed for the façade of the Cathedral of St. Mary of the Flower at Florence. As architect and engineer it appears that he became a cosmopolitan, in painting it was hardly so. He is most delightful in his early phase which is represented by a bride-chest in the Wheelwright collection, Boston. It represents Prince Paris insolently appraising the charms of the rival goddesses, and at the right riding Troywards in disregard of the despair of forsaken Œnone. The classical theme is tinged with mediævalism, naturalized as Sienese. Later pictures, such as The Nativity, Figure 68, in the Sienese gallery, show Francesco uneasy, twisting his figures for grace and display of knowledge, working over the old landscape formulas in a semi-realistic sense, adding classical architecture, generally trying to break the bounds of the old idealism. The result is restlessness or at best an ambiguous charm. Siena is beginning to regret her isolation, to make vain efforts to overtake the tide of humanistic realism, to envy Florence, and even Perugia and Cortona. From the point of view of the Renaissance she was two generations behind, and no longer indifferent to the fact. [Illustration: FIG. 67. Neroccio di Landi. Portrait of a Girl.—_Widener Coll., Elkins Park, Pa._ ] Not merely Francesco di Giorgio tries to do in a decade the work of a century, but such younger contemporaries as Fungai and Pacchiarotti look to Florence or Umbria. Siena was given no time to reconstruct, and her old beautiful art could not readily assume new forms. Siena never assimilated the Renaissance. It invaded her, killed her native art and substituted one without local flavor. Before Francesco di Giorgio died, in 1502, he had seen Luca Signorelli called to Siena and the clever decorator Pintorricchio. Siena no longer trusted her own artists. Francesco probably took little note of the advent in 1501, of a young Piedmontese painter, Antonio Bazzi,[27] nicknamed Sodoma, yet with Sodoma remained what little future there was in Sienese painting. [Illustration: FIG. 69. Sodoma. Vision of St. Catherine of Siena. Fresco.—_S. Domenico, Siena._ ]