Ada Lovelace and the Machine That Might Compose

Augusta Ada Byron was born in London in December 1815, the only legitimate child of the famous poet Lord Byron. She never really knew him; her parents separated within weeks of her birth, and he left England for good soon afterwards. Her mother, Annabella, who loved mathematics, was determined that her daughter should not inherit her father's restless, poetic temperament. As a result, Ada was educated in mathematics and science, subjects rarely offered to girls in the early nineteenth century. The strategy worked better than her mother may have expected. Ada was an eager learner, and she had the good fortune to be taught by capable tutors, including the scientist and writer Mary Somerville. Her imagination, however, remained as active as her father's. Even as a teenager, she drew plans for a flying machine after studying the anatomy of birds. In 1833, at a social gathering, Ada was introduced to the mathematician Charles Babbage, who showed her a small working part of his Difference Engine, a mechanical calculator. She was fascinated, and the two began a long correspondence. By then Babbage was designing something far more ambitious, the Analytical Engine, which could be given instructions on punched cards. It was never completed in his lifetime, but its plan contained many ideas found in modern computers. The achievement for which Ada is best remembered came in 1843. She translated an article about the Analytical Engine, written in French by an Italian engineer, and added her own notes. These notes were about three times longer than the article itself. In them she described, step by step, how the engine could calculate a sequence of numbers known as Bernoulli numbers, which many historians regard as the first published computer program. More remarkable than the program was her vision. Ada realised that the engine might handle not only numbers but any information that could be expressed in symbols. In principle, she wrote, it might even compose music. At the same time she was careful to add that the machine could only do what it was told to do; it could not originate anything by itself, a point still debated in discussions about artificial intelligence. Her work was largely forgotten for a century. When early computer scientists rediscovered it, her reputation grew, and in the late 1970s a programming language was named Ada in her honour.