During her days as a park ranger, Lucia Perillo loved nothing more than to brave the Cascade Mountains alone, taking special pride in her daring solo skis down the raw, unpatrolled slopes of Mount Rainier. Then, in her thirties, she was diagnosed with multiple sclerosis. In I've Heard the Vultures Singing, Perillo confronts, in stark but funny terms, the ironies of being someone with her history and gusto for life being suddenly unable to walk. ("Ground-truthing"...