The two rivers in “A Separate Peace” are very different, and they serve to reinforce the idea that Gene and Finny are two very different people, and that perhaps these differences cannot be overcome. The Devon River is freshwater, and the Nagaumasset is salt water. The Devon River, like Finny, is clear and innocent: “the fresh-water Devon above the dam where we'd had so much fun, all the summer." The qualities of the river are very like the qualities of Finny. It suggests calm (above the dam), innocence (fresh water) and fun. Conversely, the Nagaumasset is described as. “ugly, saline, fringed with marsh, mud and seaweed.” This is meant to symbolize Gene, who has a dark side in comparison to Finny. Gene is jealous, and his jealousy eventually causes him to spitefully push Finny from the tree. The fact that the Devon River eventually flows into the Nagaumasset is also no accident. When two rivers combine, each takes on the other’s qualities. Unfortunately, this means the Devon River would no longer be freshwater, pure, and would take on the ugly saline qualities of the other river. This is what happens to Finny; as hard as he tries to retain his innocence, Gene ruins it, not just by shoving him from a tree, but by ruining Finny’s ideal of their friendship.