Renaissance_ A Short History, The - Johnson, Paul [63]
Yet the fact remains that this panel is one of the rare occasions that a patron got what he had ordered. Leonardo’s reputation for nondelivery—as one pope put it: “Leonardo? Oh, he is the man who does not finish things”—was compounded by his passion for experiment, which produced disasters of a different kind but equally infuriating to those who paid. The Sforzas asked him to paint scenes on the walls of the refectory of Santa Maria delle Grazie in Milan, and he actually completed the Last Supper, which was instantly admired for its highly original composition and the striking interest of the faces. But his experimental techniques led to its rapid deterioration, and the other scenes never emerged. Other ambitious wall scenes, in Milan and Florence, came to nothing, or little has survived. On the other hand, Leonardo produced a design for the crossing tower of Milan Cathedral, worked on a huge bronze equestrian statue, accepted the appointment of “architect and general engineer” to the ruffianly warlord Cesare Borgia and produced various large-scale cartoons, one of which survives, for projected paintings. He worked on muscular power, optics, hydraulics, articulated flying machines, bastions and siege engines, facial expressions and human psychology, all of these preoccupations being lavishly illustrated in notebooks and detached sheets. The comparison with Coleridge is irresistible: notes took the place of finished work. As with Piero della Francesca, Leonardo’s interest in geometry grew. It was, perhaps, the dominant theme of the last years of his life, though he also seems to have dwelt obsessively on the pros-pects of catastrophic storms and other extreme weather conditions. These years were spent in or near the French court, where François I became his ideal patron: reverential, generous, unharassing, content merely to have in attendance this great Italian seer, who could do so many remarkable things when he chose and whose conversation was a Renaissance in itself.
Leonardo’s influence on his immediate successors or near contemporaries, including Raphael, was immense, both in the organization of large-scale painting and in painting techniques. He wrote extensively on painting, though nothing was actually published until the mid–seventeenth century. But his views were known—that, for instance, “correct” mathematical perspective did not actually produce what we think we see and required correction. Where as the Greeks used a special curvature or entasis, Leonardo blurred outlines, a technique that came to be known as sfumato and that the adoption of painting in oils made highly effective. He was therefore behind the shift away from the strong outlines preferred in the fifteenth century, of which Botticelli, for example, made such brilliant use, to the rounded, more painterly techniques of the sixteenth century, involving a large degree of shadowing, the systematic use of highlights and chiaroscuro.
This was one of the most significant and lasting innovations in the history of Western painting. Leonardo also introduced, or at any rate made