This affectionate study of the Mexican temper is ''one of the most charming travel books ever written.'' - The Atlantic Monthly Before returning to the Old World after World War II, Sybille Bedford resolved to see something more of the New. ''I had a great longing to move,'' she said, ''to hear another language, eat new food, to be in a country with a long nasty history in the past and as little present history as possible.'' And so she set out for Mexico - and, incidentally, to write what Bruce Chatwin called the best travel book of the twentieth century, ''a book of marvels, to be read again and again and again.''