In a large, wide, and heavy copper pot or Dutch oven, warm the olive oil over medium heat. Add the onion, carrrot, celery, and rosemary, reduce the heat to medium-low, and sauté, stirring occasionally, until the vegetables are well softened, about 10 minutes. Add the ribs and sausages. Sauté until lightly browned all over, about 25 minutes. Stir frequently to prevent the vegetables from burning. Pour in the wine and stir to scrape up any browned bits from the bottom of the pan. Cook to evaporate the alcohol, about 3 minutes. Add the tomatoes, cover, and simmer, stirring occasionally, until the sauce is thick and the meat is so tender it falls off the bones. 2½ to 3 hours. Remove from the heat, remove rosemary, taste for salt, and cover to keep warm.

Thirty minutes before the meat is done, make the polenta: In a large saucepan, bring the water to a rapid boil over high heat. Add the polenta and salt. Reduce the heat to medium-low and, using a wooden spoon, stir constantly in the same direction to prevent lumps from forming and to keep the boiling temperature constant. This is important if the polenta is to become properly soft and creamy. Cook until it is so thick that it begins to resist stirring and pulls away easily from the sides of the pan, about 30 minutes. If the polenta is quite thick but still not pulling away easily from the pan, add a little boiling water and continue to stir until it is ready. Pour into a large serving platter alongside the stewed meat. Serve at once.