Urbanization, place of experiment and how the electric fish was caught by Emil du Bois-Reymond.
Laboratories, along with the researchers, organisms, instruments, and experiments associated with these places of investigation, are not isolated from the world beyond their physical and institutional boundaries. Both laboratories and the cities in which they are embedded are subject to change, as was most dramatically apparent in their dynamic and far-reaching transformation during the industrial revolution of the nineteenth century. Using the example of Berlin and the institutionalization of experimental physiology by Emil du Bois-Reymond, in this paper I study experimental work on frogs and fish in order to demonstrate how a city and a laboratory cooperate in the production of knowledge. Emil du Bois-Reymond's research on electric fish illustrates how an exotic organism and a laboratory came together in a city and how the research was driven by innovation and development in urban and industrial technology. Ongoing changes in the urban landscape entered du Bois-Reymond's workplace and became part of the material culture of his experimental physiology and his attempts to demonstrate that the electric fish discharge is fundamentally similar to the excitation of nerve and muscle.