The National Portrait Gallery in London has acquired the only surviving photographs of 19th-century mathematician Ada Lovelace, a group of three daguerreotypes that were originally offered at Bonhams in June 2025 with an estimate of £80,000 to £120,000. The lot was withdrawn from auction and the museum secured it via a private treaty sale, a confidential negotiation process that allows institutions to purchase significant artworks directly from private owners. Two of the daguerreotypes were taken by French photographer Antoine Claudet around 1843, the year Lovelace published her foundational paper on Charles Babbage's Analytical Engine, while the third, by an unknown photographer, reproduces an 1852 portrait by Henry Wyndham Phillips showing Lovelace near the end of her life.
This acquisition matters because it brings into a public collection the only known photographic images of a pivotal figure in the history of computing and mathematics. Lovelace is widely recognized for writing the first algorithm intended for a machine and for foreseeing that computers could go beyond number-crunching to create music and art, ideas that resonate with current debates about artificial intelligence. The private treaty sale also highlights an increasingly important mechanism for museums to expand their collections outside the competitive auction room, allowing institutions to secure culturally significant works while keeping them in the public domain.