What drew Leonardo from Florence to Milan we do not surely know. Probably he was called directly by the Duke Lodovico Sforza to undertake the colossal equestrian statue of his father Francesco. Moreover, Leonardo seems to have achieved notoriety at Florence without gaining much confidence or achieving much success. After all, he had rather little to show for his genius—just his sketch books and his good intentions in unfinished masterpieces. He seems, too, never to have mastered the practice which ever brought the best commissions, fresco painting. Thus he had every reason to seek new fortunes. He heralded his coming to Milan with the most truthfully boastful of letters in which he arrogated to himself all ability as an inventor, civil and military engineer, painter, sculptor, and architect; and he entered the presence of Lodovico bearing a silver lute wrought in the form of a horse’s skull. This dramatic entrance was the forecast of arduous duties as an entertainer. He sang, told anecdotes and fables, arranged pageants and masques, conducted debates on his art—in short, accepted the thousand and one duties and distractions of a courtier. He painted the portraits of the Duke’s mistresses, and it is possible that we have the girlish figure of Cecilia Gallierani in the lady with an Ermine[54] at Cracow. The forms and feeling are entirely like Leonardo’s work in the early eighties. He agreed to do an altar-piece for the Church of San Francesco, and delivered it only after a delay of twenty-three years. This most postponed of pictures is the version of the Madonna of the Rocks now at London. Meanwhile Leonardo’s constant concern was “the horse,” as he calls it. For seven years he worked at a rearing horse with a fallen foe trodden beneath. It is shown in many drawings. It was too sensational a theme to please him in the long run. So in 1490, spurred by the risk of losing the job, he restudied the horse, using the walking motive, which had come down from classical antiquity. Eventually the clay model was set up before the Sforza castle, just in time for the invading French archers to make a target of it. The rider was never even definitely planned. The whole project remained a chagrin to Leonardo even after the horse itself had disappeared. One day in Florence he civilly accosted Michelangelo who turned on him with the taunt—“Thou who did’st model a horse and could’st not cast it in bronze.” Amidst the distractions of the court, the irksomeness of the rashly undertaken Sforza monument, and the increasing passion for scientific research, Leonardo managed to carry through his single monumental work, the Last Supper, in the refectory of Santa Maria delle Grazie.