A correspondent writes referring to Mark Twain's works _Life on the Mississippi_, _The Adventures of Tom Sawyer, and _Adventures of Huckleberry Finn_: ~~~~~ It seems to me that one of the major themes of these works, as well as the others I have read and re-read is an abiding passion for the environment and nature. I have viewed Twain as a humorist, social commentator, editorial writer, travel writer, but never as a nature writer. Is he not our first John Muir, Aldo Leopold, Rachel Carson, etc? Are there any books or articles that you know of that touch upon this aspect of his writing? ~~~~~ I find references in _Mark Twain's Library: A Reconstruction_ to Henry David Thoreau and Dean Sage -- environmental writers who Twain admired. Are there any recommended journal articles or essays that address this aspect of Mark Twain's works? Thanks, Barb