ArgumentThe article examines the organizational patterns of nineteenth-century Swiss Alpine geology. It argues that early and middle nineteenth-century Swiss geognosy was shaped in genealogical terms and that the patterns of genealogical reasoning and practice worked as a vehicle of transmission toward the generalization of locally gained empirical knowledge. The case study is provided by the Zurich geologist Albert Heim, who, in the early 1870s, blended intellectual and patrilineal genealogies that connected two generations of fathers and sons: Hans Conrad and Arnold (...) Escher, Albert and Arnold Heim. Two things were transmitted from one generation to the next, a domain of geognostic research, the Glarus Alps, and a research interest in an explanation of the massive geognostic anomalies observed there. The legacy found its embodiment in the Escher family archive. The genealogical logic became visible and then experienced a crisis when, later in the century, the focus of Alpine geology shifted from geognosy to tectonics. Tectonic research loosened the traditional link between the intimate knowledge of a territory and the generalization from empirical data. (shrink)