In 1494, Da Vinci was invited to Milan by the Duke Lodovico Sforza, who appointed him Director of the Academy of Painting and Architecture, which he had recently revived with additional splendor and encouragement. During his residence there, he painted but little, with the exception of his celebrated picture of the Last Supper, a description of which will be found in a subsequent article. As Director of the Academy, he banished all the dry, gothic principles established by his predecessor, Michelino, and introduced the beautiful simplicity and purity of the Grecian and Roman styles. Lanzi says that in this capacity, “he left a degree of refinement at Milan, so productive of illustrious pupils that this period may be ranked as the most glorious era of his life.” The Duke engaged Lionardo in the stupendous project of conducting the waters of the Adda, from Mortesana, through the Valteline, and the valley of the Chiavenna to the walls of Milan, a distance of nearly two hundred miles. Sensible of the greatness of this undertaking, Lionardo applied himself more closely to those branches of philosophy and mathematics which are most adapted to mechanics, and finally accomplished this immense work, greatly to the astonishment and admiration of all Italy. He executed the model for a colossal bronze equestrian statue of the Duke’s father, Francesco Sforza, and would have completed it, but the Duke’s affairs were becoming greatly embarrassed, so that the necessary metal (200,000 lbs.) was not furnished. In 1500, Lodovico Sforza was overthrown in battle by the French, made prisoner, and conducted to France, where he soon after died in the castle of Loches. The Academy was suppressed, the professors dispersed, and Lionardo, after losing all, was obliged to quit the city, and take refuge in Florence. DA VINCI’S “BATTLE OF THE STANDARD.”