Put the oil, butter, and the onions in the pot and heat over medium.  Cook until the onions are translucent, about 15 minutes since you're starting from a cold pot.  Add the celery and the carrots, stir so that they are well coated, and cook for about 2 minutes.

Add the ground beef, a large pinch of salt and several grindings of pepper.  Cook the beef, stirring and seperating it with a fork, until the beef is no longer raw (it will still be pink in places.)

Add the milk and simmer gently, stirring occasionally, until the milk has evaporated.  Add about ⅛ tsp. freshly grated nutmeg and stir.  Add the wine and simmer until it has evaporated.  Add the tomatoes and stir to thoroughly coat all the ingredients.  Once the tomatoes begin to bubble, reduce the heat and simmer very gently for at least 3 hours.  As the sauce is simmering, check occasionally, and if the mixture begins to dry out, add ½ cup water whenever necessary.  After simmering for the 3 hours, the sauce is done when there is no water left and the fat has separated from the sauce.  Add salt to taste.

Cook the pasta according to the package directions.  Add the remaining tablespoon of butter to the hot cooked, drained pasta, toss the pasta with the sauce and serve.  Pass the grated Parmesan at the table.