Hal, It seems that I have run across a study or two about how the river affected the communities along it. I, for one, am very interested in how Twain represents and imaginatively reconstructs the Mississippi to serve his fictive purposes. My chapter in the proposed Mark Twain's Geographical Imagination addresses some of these issues. Of course, being a "river rat" myself helps. For example, I have intimate knowledge of how Alton's location was central to that community's development, culturally and economically. Regards, Sandra Littleton Uetz