Huygens ING<\/a>, offers users an entrance to the combined content of learned correspondences of various seventeenth-century Dutch scholars; around 20,000 letters in total. After each search, the tool automatically suggests other keywords related to the query, while topic modelling allows it to suggest letters with related material. It also features dynamically generated visualizations; for every search the network of correspondents can be displayed, and the places of despatch and receipt represented on a map.<\/p>\nIn this presentation, Dr Zuidervaart provides an outline of the development of the ePistolarium, including some highlights and pitfalls. He concludes by focusing on a feature of the ePistolarium made possible by named entity recognition, namely the opportunity to dynamically visualize networks of influence and co-citation within selected sets of letters. He uses this feature to explore the well-known case of Christiaan Huygens<\/a>\u2019 observations on the planet Saturn, comparing the results generated by the ePistolarium with the existing state of knowledge derived from current literature.<\/p>\n