Simon Flexner and Hideyo Noguchi’s work discusses venom research from the perspective of immunology. They could draw on a much broader pool of resources than Mitchell had available—conceptual, methodological, and material. The mechanism of venom poisoning served as a model for the immune reaction and as a convenient tool for its investigation. Drawing heavily on Paul Ehrlich’s conception of the immune response, Flexner and Noguchi examined the activity of various components of snake venoms. They aimed to establish the existence and agency of substances that were not directly observable, while stabilizing very complex experimental environments. These methodological challenges linked their work with contemporaneous medical and biological experimentation in bacteriology and in seemingly remote fields, such as experimental embryology. The chapter illustrates how venom researchers and other experimenters in the life sciences addressed the problems of validating hypotheses about invisible entities and how they relied on standard units and thresholds to control the variability of experimental conditions, organisms, and biological specimen. The chapter also charts the emerging discussions about how to write scientifically. One of the main motivations for the turn to so-called deductive composition was the notion that “composing deductively” could facilitate the researcher’s understanding of a paper's main points.
Keywords: snake venom, experimentation, Paul Ehrlich, experimental reports: composing deductively, bacteriology, immunology, unobservables, hypothesis, Simon Flexner, Hideyo Noguchi