It was at one of these soirees when Ada was 17 that she met the wealthy mathematician and inventor Charles Babbage, himself aged 41. What would grow to be a life-long and meaningful friendship between kindred spirits was started by Ada’s fascination with Babbage’s inventions. Around the time Ada first met Babbage in 1833, he had been working on an invention called the Difference Engine for about 10 years. Babbage’s goal was to create a machine that could automatically carry out logarithmic and trigonometric functions. The Difference Engine was a radical concept, ideally producing rapid and error-free calculations—something which caught the attention of the British government, which had financed Babbage’s idea. Following their initial introduction, Ada and her mother were invited by Babbage to see his partially complete Difference Engine in action.
Although the Difference Engine was ultimately never brought to fruition, Babbage subsequently envisaged an even more ambitious device—the Analytical Engine. His earliest notes on the project appear in 1834, roughly a year after he and Ada first met. This radical invention concept (more on that soon) has been recognized now as the world’s first mechanical computer. Babbage had been inspired by the Jacquard loom technology, developed by Joseph-Marie Jacquard and patented in 1803. The Jacquard loom was a revolutionary technology in which a series of punched cards guided various silk threads in specific patterns to rapidly weave beautiful silk fabrics. There often were over 2,000 cards per design, resulting in ornate patterned textiles. Based on the loom’s card concept and the increased speed of high-quality silk fabric production it afforded, Babbage devised a similar automated system for working out solutions to complex mathematical equations.
Babbage’s Analytical Engine design was limited to the technologies available in the first half of the 19th century. The mechanics Babbage described included the Jacquard-inspired punched cards to guide the operation of the Analytical Engine. Cogwheel components were to be lifted by power transmission rods and moved to other parts of the Engine. The proposed size of the Engine was massive—roughly the size of a modern-day van. Though difficult to envisage in form, it had in concept components that we would now recognise in modern computers: advanced computing power, memory, branching and loops, and even an associated printer. Babbage discussed the mechanics and plans for the Analytical Engine readily and often, but Ada genuinely shared in the vision for what the invention could do, and she became one of the most knowledgeable people in the world on the Analytical Engine. Between in-person visits and numerous letters, Ada and Babbage built what has been viewed as one of the great partnerships in the history of computer science.
Concurrent with her and Babbage’s correspondence, Ada’s life followed a paradoxically conventional and exceptional path for a woman of her time. Marrying “well” at age 19 to William King, who eventually became the 1st Earl of Lovelace, she had three children in as many years. Lovelace would prove to be a supportive, albeit somewhat boring, spouse for Ada, who encouraged her scientific pursuits. Filling a deep need for mental stimulation outside of the domestic and social sphere, she enlisted as a personal tutor the esteemed mathematician, Augustus De Morgan. She was voracious in her studies, which concerned De Morgan in so far as its impact on her health. Although she was clearly dedicated to the subject, her tutor noted that she would not have likely been top of the class in a traditional setting such as Cambridge. He also noted (with some of the aforementioned concern for her well-being) her strong desire to push beyond the state of current mathematical knowledge. Overall, De Morgan denigrated her prospects in mathematics due to her sex. He was very much echoing the unfair realities of the time.
Fast forward several years, and an opportunity presented itself to Ada which would lead to her most memorable contribution. It was Ada’s intimate understanding of the Analytical Engine that prompted Babbage’s associate Charles Wheatstone to enlist her help: in 1842, Babbage had given a lecture at the University of Turin, Italy, about the Analytical Engine. An Italian engineer named Luigi Federico Menabrea had been in attendance and was fascinated with Babbage’s invention. He soon after published his notes from the talk in a well-respected technical journal. Ada was asked initially to simply translate the work from its published French, but would go on to add corrections and her own extensive commentary, arranged in sections from Notes A to G. Her contributions were three times as long as the original text.
It was in these notes that she demonstrated not only her solid mathematical comprehension but also described what we would now recognise as a computer programme. This can be found in Note G, where Ada described in detail how the Analytical Engine could be prompted to carry out complex calculations, such as deriving Bernoulli numbers independently. She also explained her vision of the Analytical Engine’s potential to process abstract concepts as symbols, a revolutionary idea that was many decades ahead of her time. Furiously writing back and forth with one another, Babbage encouraged Ada to pursue her additions and commentary in these notes.
Babbage rightly credited Ada with her contributions to the notes and translation, stating in his autobiography that she had performed nearly all the algebraic equations, and even had corrected his only calculations regarding the Bernoulli numbers. Numerous letters between the two exist today, detailing the vision and high aptitude both parties brought to the table, which was crystallised in the Menabrea paper notes. Despite this explicit evidence of Ada’s skills and work, some modern commentators have unfairly questioned the extent of her input and the extent of her own skills.
Sadly, the Analytical Engine was never brought to full fruition. Following the completion of the Menabrea paper notes in 1843, Ada wrote to Babbage with a proposal. She offered to essentially market the Analytical Engine, ensuring it was shown to and understood by the influential people in Victorian Britain. Ada clearly understood the potential of the Analytical Engine, likely also realising that Babbage himself, for all his brilliance, would struggle to successfully capture the interest of wider society. In a move that is still puzzled over by modern biographers of the pair, Babbage flat-out rejected Ada’s help. The only record of his reaction was a note on the letter Ada had sent him stating that he had seen Ada that day and “…refused all the conditions.”