Haggard and half-starved, the author Heinrich Harrer and a companion, Peter Aufschnaiter, arrived in Tibet in early 1946 after a hazardous 21-month flight from a wartime internment camp in India. Officials ordered them to leave, then relented. Extraordinary experiences befell Mr. Harrer during seven years in the veiled land beyond the Himalayas. Before China invaded Tibet, he became a friend and tutor of the Dalai Lama, its spiritual and temporal ruler.