One of the central American metaphors is that of the melting pot, but in the northern Midwest winters are long and melting does not happen easily. Along the banks of the northern Mississippi, one still finds the music of wave after wave of immigrants, people who came thousands, hundreds, or just a few years ago. Each group has been affected by its surroundings and its neighbors, but each has also retained a cultural cohesiveness that is much rarer as one moves south.