Twenty-five years ago, TERRY TEMPEST WILLIAMS’ mother died of ovarian cancer, and she left Terry 54 journals, one for each year of her life. Later, when Terry went to read them, longing to hear her mother’s voice again, she found that each one was blank. In her book, “When Women Were Birds: Fifty-Four Variations on Voice,” Williams meditates on why her mother might have left the journals unfilled. What did that signify to her mother? What was her mother telling her?