Book excerpt: Here is an entertaining collection of famed conservationist John Muir’s most exciting adventures in nature, representing some of his finest writing. From the famous avalanche ride off the rim of Yosemite Valley to his night spent weathering a windstorm at the top of a tree to death-defying falls on Alaskan glaciers, the renowned outdoorsman’s exploits are related in passages that are by turns exhilarating, unnerving, dizzying, and outrageous.