Augusta Ada Byron, Countess of Lovelace, is known for reasons that have little to do with her own life and accomplishments. While she was alive, she lived in the shadow of her father, the poet Lord Byron, even through he all but abandoned her when she was still an infant. In the past few years, she has once again become a figure of interest as one of the few who collaborated with Charles Babbage in his pioneering work on the Difference and Analytical Engines. Today one finds the word “ADA” followed by a trademark symbol, indicating the Department of Defense’s language of choice for complex defense-related computing systems. This book, the third in the MIT Series in the History of Computing, gives a full account of Ada’s life that focuses on the woman herself. It is thoroughly researched and documented, with the author’s assertions buttressed by a wealth of quotations from letters and documents written by Ada and her contemporaries.

Of the author’s account of Ada’s life and work, only one chapter focuses on her collaboration with Babbage and his computing machinery (although Babbage appears throughout the book in other contexts). This is as it should be--for Ada, computing machines were but one of her many interests. Still, it is this phase of her life more than any other that elicits the most interest today. Ada’s contributions to computing, especially her translation and annotation of L. Menabrea’s “Sketch of the Analytical Engine,” are the focus of Chapter 4 of the book. From this description, it appears that Ada’s present reputation as the world’s first computer programmer is undeserved. In the author’s words, “. . . it was the formal beauty and surprising, seemingly magical results of mathematical reasoning and processes that entranced her. For the subject itself she had little natural talent; its techniques, despite hard work, continued to elude her; its symbols remained the doings of ‘mathematical sprites and fairies’.” Yet it seems to this reviewer that this view of mathematics was not without its compensation: such a view allowed her to see the wider implications of automatic machinery than Babbage himself was able to foresee. It is Ada, not Babbage, whose statements about the Engine’s reasoning powers are often quoted in introductions to modern texts on artificial intelligence; perhaps also her “mystical” approach to mathematics is the reason a programming language has been named after her.

Ada’s difficulties with understanding Babbage and the mathematics of her day must be understood in the proper context of not only the social atmosphere of being a woman in nineteenth-century England, but also of Babbage’s difficulties in collaborating with anyone on his computing projects. The author of this book firmly establishes Ada’s proper place. If this may diminish her reputation as a mathematician, it should also increase our understanding of this remarkable woman and the age in which she lived. From this biography, Ada emerges as a less mysterious, but no less fascinating, figure.