Happy Birthday Ada Lovelace

from John McCormick
mccormick@cs.uni.edu

On December 10, 1815, Anna Isabella (Annabella) Byron, whose husband was Lord Byron, gave birth to a daughter, Augusta Ada. Ada's father was a romantic poet whose fame derived not only from his works but also from his wild and scandalous behavior. His marriage to Annabella was strained from the beginning, and Annabella left Byron just a little more than a month after Ada was born. By April of that year, Annabella and Byron signed separation papers, and Byron left England, never to return.

Byron's writings show that he greatly regretted that he was unable to see his daughter. In one poem, for example, he wrote of Ada,

        I see thee not. I hear thee not.
        But none can be so rapt in thee.

Byron died in Greece at the age of 36, and one of the last things he said was,

        Oh my poor dear child! My dear Ada!
        My God, could I but have seen her!

Meanwhile, Annabella, who was eventually to become a baroness in her own right, and who was herself educated as both a mathematician and a poet, carried on with Ada's upbringing and education. Annabella gave Ada her first instruction in mathematics, but it soon became clear that Ada's gift for the subject was such that it required more extensive tutoring. Ada received further training in mathematics from Augustus DeMorgan, who is today famous for one of the basic theorems of Boolean algebra, which forms the basis for modern computers. By the age of eight, Ada also had demonstrated an interest in mechanical devices and was building detailed model boats.

When she was 18, Ada visited the Mechanics Institute to hear Dr. Dionysius Lardner's lectures on the "difference engine," a mechanical calculating machine being built by Charles Babbage. She became so interested in the device that she arranged to be introduced to Babbage. It was said that, upon seeing Babbage's machine, Ada was the only person in the room to understand immediately how it worked and to appreciate its significance.

Ada and Babbage became good friends and she worked with him for the rest of her life, helping to document his designs, translating writings about his work, and developing programs to be used on his machines. Unfortunately, Babbage never completed construction of any of his designs. Even so, today Ada is recognized as being the first computer programmer in history. That title, however, does not do full justice to her genius.

Around the time that Babbage met Ada, he began the design for an even more ambitious machine called the "analytical engine," which we now recognize was the first programmable computer. Ada instantly grasped the implications of the device and foresaw its application in ways that even Babbage did not imagine. Ada believed that mathematics eventually would develop into a system of symbols that could be used to represent anything in the universe. From her notes, it is clear that Ada saw that the analytical engine could go beyond arithmetic computations and become a general manipulator of symbols, and thus it would be capable of almost anything. She even suggested that such a device could eventually be programmed with rules of harmony and composition so that it could produce "scientific" music. In effect, Ada foresaw the field of artificial intelligence over 150 years ago.

In 1842, Babbage went to Turin, Italy, and gave a series of lectures on his analytical engine. One of the attendees was Luigi Menabrea, who was so impressed that he wrote an account of Babbage's lectures. At age 27, Ada decided to translate the account into English, with the intent to add a few of her own notes about the machine. In the end, her notes were twice as long as the original material, and the document, "The Sketch of the Analytical Engine," became the definitive work on the subject.

It is obvious from Ada's letters that her "notes" were entirely her own and that Babbage was acting as a sometimes unappreciated editor. At one point, Ada wrote to him,

"I am much annoyed at your having altered my Note. You know I am always willing to make any required alterations myself, but that I cannot endure another person to meddle with my sentences."

Ada gained the title Countess of Lovelace when she married Lord William Lovelace. The couple had three children, but Ada was so consumed by her love of mathematics that she left their upbringing to her mother. For a woman of that day, such behavior was considered almost as scandalous as some of her father's exploits, but her husband was actually quite supportive of her work.

In 1852, Ada died from cancer. Sadly, if she had lived just one year longer, she would have witnessed the unveiling of a working difference engine built from one of Babbage's designs by George and Edward Scheutz in Sweden. Like her father, Ada lived only until she was 36, and, even though they led much different lives, she undoubtedly admired Byron and took inspiration from his unconventional and rebellious nature. At the end, Ada asked to be buried beside him at the family's estate.

Ada Lovelace biography material excerpted from "Programming and Problem Solving with Ada 95" by Dale, Weems, and McCormick. Jones & Bartlett Publishers.

In the 20th century, navy commander John Cooper honored Ada Lovelace by naming the US Department of Defense's new programming language after her. Ada is perhaps the only language to have applied software engineering principles to its design. After several years of requirements gathering, William Whitaker's team produced four generations of language specifications (strawman, woodenman, tinman, and ironman). The DOD then held a competition to design the language. Cii Honeywell Bull of France led by Dr. Jean Ichbiah won the final competition. For his accomplishments, Dr. Ichbiah was awarded the Legion d'Honneur by the President of France.

Since its first ISO standard was approved in 1987, Ada has evolved with new standards in 1995 and 2005. Ada was the first object-oriented language to have an international standard. Ada is the language of choice in projects where failure is not an option. The safety critical software on board nearly every, high speed train, aircraft, and spacecraft is written in Ada. Praxis High Integrity Systems, the only company known to give unrestricted warranties on the software they develop, work exclusively in a subset of Ada called SPARKAda. SPARKAda provides the means for proving that software meets its specification. Replacing much of the laborious testing of high integrity software with rapid mathematical proofs allows Praxis to consistently underbid competitors using more mainstream but less precise languages. Praxis is currently developing the software for the United Kingdom's new en-route air traffic control system. At an estimated 1.2 million lines of code, it will be the largest software system ever formally verified.

The same feedback that Ada provides developers of mission-critical software makes it easier for beginners to learn programming. The stability of the language allows compiler writers to concentrate more on the human side of programming than on adding new features. The GNU Ada Translator (GNAT) includes an expert system that analyses a student's programming style and a database of previous students' errors to tailor its syntax error messages. Introductory programming classes taught using Ada have consistently higher retention rates than the more popular languages. Perhaps Ada Lovelace would be pleased that her language namesake is particularly effective in retaining women in our profession.