<b>Jeannette Walls's <I>The Glass Castle</i> was "nothing short of spectacular" (<I>Entertainment Weekly</i>). Now she brings us the story of her grandmother -- told in a voice so authentic and compelling that the book is destined to become an instant classic. </b><P>"<I>Those old cows knew trouble was coming before we did</i>." So begins the story of Lily Casey Smith, in Jeannette Walls's magnificent, true-life novel based on her no-nonsense, resourceful, hard working, and spectacularly compelling grandmother. By age six, Lily was helping her father break horses. At fifteen, she left home to teach in a frontier town -- riding five hundred miles on her pony, all alone, to get to her job. She learned to drive a car ("I loved cars even more than I loved horses. They didn't need to be fed if they weren't working, and they didn't leave big piles of manure all over the place") and fly a plane, and, with her husband, ran a vast ranch in Arizona. She raised two children, one of whom is Jeannette's memorable mother, Rosemary Smith Walls, unforgettably portrayed in <I>The Glass Castle</i>. <P>Lily survived tornadoes, droughts, floods, the Great Depression, and the most heartbreaking personal tragedy. She bristled at prejudice of all kinds -- against women, Native Americans, and anyone else who didn't fit the mold. <I>Half Broke Horses</i> is Laura Ingalls Wilder for adults, as riveting and dramatic as Isak Dinesen's <I>Out of Africa</i> or Beryl Markham's <I>West with the Night</i>. It will transfix readers everywhere.