The narrative sputters when it shifts to Shattuck’s time in Rhode Island, where family had lived, his relationship with his wife, Jenny, and an unfortunate accident years ago with a boat’s gunwale that resulted in the loss of the top part of his middle finger. Reliving Thoreau’s hiking and canoeing adventures in northern Maine’s Allagash Wilderness Waterway gets Shattuck back into his enthusiastic, poetic stride, describing the same black flies that had also accosted Thoreau, listening to bird song, and observing a double rainbow.