But when the painting was finished, it was not according to the instructions set forth in the contract. Leonardo had too independent a mind to be bound by conformity. Nor was it completed on time. Indeed, for twenty years the quarrel between the Fraternity and the painters went on. After ten years, Ludovico was asked to intervene for the money owed; after he failed, another ten years went by and the King of France himself was finally asked to settle the dispute. Leonardo wanted his one hundred ducats and the Fraternity offered twenty-five. Eventually, a secret agreement was arrived at and the painting was restored to Leonardo and Ambrogio. Leonardo’s painting, the masterpiece entitled the “Virgin of the Rocks,” now hangs in the museum of the Louvre in Paris. The day this contract was signed, Leonardo walked back through the city to Ambrogio’s studio near the Ticino gate. He was low in spirits from reading the petty instructions of the contract, and, in this mood, he became aware of the city streets and crowds about him. The noise, the confusion, the smells—yes, the smells were the worst. Garbage, filth, and dust were in heaps where the last rainwater had left them and they buzzed with flies. Moreover the houses were jammed together and shopkeepers crowded their wares to the edges of the streets, leaving just enough room for the occasional horseman to get through. Latrines were only for the better houses; here, the streets, alleys and even open doorways were toilets. People flung their scraps out of the window and at night in the poorly lit streets could be heard the scurrying of rats. Leonardo stopped, thinking half aloud: “Two levels. Streets running one above the other—one for pedestrians and one for carts and horses. Yes, and cutting through the whole city a system of canals to carry the city’s waste to a river or to the sea. Why not even ten cities of, say, five thousand houses in each—say, no more than thirty thousand people to a city?” Intent now on his thoughts he hurried to his home, his mind busy with his visions of new cities. During the years 1484 and 1485 the bubonic plague swept Italy—the same dreaded Black Death so prevalent in medieval times. Milan was one of the cities most severely stricken. Every courtyard became a hospital and the streets were deserted except for the rumbling carts picking up the dead. On the roads from the city were lines of refugees fleeing to the country. Surrounding cities that had not been infected manned their fortress walls as in wartime to keep the fleeing populations out. Ludovico at first tried to protect Milan from the spread of the disease; then, frightened, he and his court fled. Even the ruler’s official documents had to be “disinfected” by perfume and then held for a period of time before he would allow them near him.