ver Cuevana 3. Eddy L. Harris is the author of the lauded travel book “Mississippi Solo” (1988), which chronicled his canoe trip down the length of the Mississippi River, from its headwaters in Minnesota to its terminus in the Gulf of Mexico. In “River to the Heart,” Harris retraces that journey as a 60-year-old, and the film explores what he discovered about both the country that was and the country that is.