Abstract“Staining is the Best Policy”. Visualization in the work of Paul Ehrlich. For nearly all of his life, the biomedical scientist Paul Ehrlich dedicated himself to work on dyes and staining at the interface between so‐called color‐chemistry and histopathology. The article begins by sketching out the field of histopathology at the junction of pathological anatomy, microtechniques, and the development of chemical dyes in the early 1870s when Ehrlich began his training as a medical student. The article explores Ehrlich's work staining (...) first tissue and blood, and then pathogens and vital staining in the 1880s. In the late 1880s and 1890s, Ehrlich experimented with dyes as therapeutic agents. Staining made the invisible visible, revealing cell structures, pathogens, or vital physiological processes within the cell itself. The article shows how visualization became an essential – albeit laborious and painstaking – element in the epistemic process of Ehrlich's work. The production of histological specimens required special skills acquired through extensive practice, especially in the techniques of visualization, manipulation, observation, and tacit understanding. These practices were needed because it was increasingly necessary to produce objective results once the various techniques of visualization came to be assessed within a discourse on objectivity. Visualization itself became an epistemic object and was ultimately “more important than the subject matter itself”. (shrink)

ArgumentThe procedure ofWertbestimmungplayed a vital role in the implementation of serum therapy and the standardization of mass-produced pharmaceuticals. In fin-de-siècle Germany, a legal framework was put in place to guarantee serum quality and safety and to minimize any associated public health risks. Because the sera were biological remedies, it was difficult to produce them in uniform quality and the procedure ofWertbestimmung, i.e. determining the potency of the serum based on an objective and comparable value, was extremely complex. Various agents such (...) as bacteria cultures, serum hosts, or test animals had to be regulated. In the years after 1895, numerous efforts to stabilize the procedures ofWertbestimmungwere undertaken by serum producers and members of the state-run survey institute responsible for overseeing serum production. Despite efforts to stabilize the framework and to generate a reliable reference system, the framework's environment and agents were in constant flux: new producers entered the market and procedures were expanded to include other biologicals as well. The article describes the dynamics involved in the sustained efforts to maintain a stable framework in the face of constant alterations between 1895 and the 1920s. (shrink)

ArgumentThis essay places some therapeutic vaccines, including particularly the diphtheria antitoxin, into their larger historical context of the late nineteenth century. As industrially produced drugs, these vaccines ought to be seen in connection with the structural changes in medicine and pharmacology at the time. Given the spread of industrial culture and technology into the field of medicine and pharmacology, therapeutic vaccines can be understood as boundary objects that required and facilitated communication between industrialists, medical researchers, public health officials, and clinicians. (...) It was in particular in relation to evaluation and testing for efficacy in animal models that these medicines became a model for twentieth-century medicine. In addition, these medicines came into being as a parallel invention in two very distinct local cultures of research: the Institut Pasteur in Paris and the Institut für Infektionskrankheiten in Berlin. While their local cultural origins were plainly visible, the medicines played an important role in the alignment of the methods and objects that took place in bacteriology research in France and Germany in the 1890s. This article assesses the two locally specific regimes for control in France and in Imperial Germany. In France the Institut Pasteur, building on earlier successful vaccines, enjoyed freedom from scrutinizing control. The tight and elaborate system of control that evolved in Imperial Germany is portrayed as being reliant on experiences that were drawn from the dramatic events that surrounded the launching of a first example of so-called “bacteriological medicine,” tuberculin, in 1890. (shrink)