Ruth Montgomery's story of a nun, as told to her by Mary McCarran, daughter of the late senator from Nevada, is a new divulgence of convent life with the why's and how-come's of entering and leaving the Order. Miss McCarran, for 32 years Sister Mary Mercy, tells her reasons for taking her religious vows, but unlike the skillful handling in Kathrya Hulme's The Van she never quite makes clear her motivations for renouncing them although she try, in the last few pages. The basic weakness herein is the sad lack of growth or change which should justify any autobiographical revelation. When Miss MaCarras remarks toward the end of the book that ""the circle had come full turn"", one is indeed inclined to feel not that she has ""returned"", but that she is right back where she started. Her description of convent life is adequate, her postion in it seems to have been secure and without temptation to leave -- yet leave she does. While she does state her own rationale for giving up her life as a religious, the decision, like most of her others, seems to be not so much her own determination as the acceptance of another's. One is left feeling that Miss McCarran still lives by the Holy vow that had almost always influenced her. Despite essential weaknesses, this remains a great area of human interest.