Isak Dinesen's "Letters from Africa, 1914–1931" … is the raw material from which the author quarried her world-famous memoir "Out of Africa," published in 1938. Reserved, stoic, and tactful, that work gave little hint of its author's painful private life, and its admirably pure and exact prose produces an effect of self-possession and self-sufficiency. The letters, an unconscious—and unself-conscious—self-portrait, were written to her mother, her brother Thomas, her Aunt Bess, and her sister Ellen, and their spontaneity reproduces the reality of the author's life in Kenya: struggle, anxiety, loneliness, with intermittent periods of elation. The letters demonstrate her culture and her intimate involvement with art, literature, and ideas—particularly social thought about the role of women—and they share with the memoir a passion for Africa, its landscape, its peoples, its plants, and its wildlife. (p. 120)

When these letters close, their author, at the age of forty-six, is returning...