History as a Tool for Natural Science: How Ernst Mach Applied Historical Methods to Physics

Historical methods have long been put to use in the making of natural knowledge. In this article, I examine the use of historical methods by nineteenth-century physicists, focusing on the Austrian researcher Ernst Mach in particular. I argue that Mach applied methods characteristic of the then-dominant historical and philological disciplines to his own discipline of physics. He construed history as a tool for the physicist. On the basis of a study of his notebooks and correspondence with the chemist-turned-historian Emil Wohlwill, I explain what he sought to achieve by means of this tool, and reconstruct the practices characterizing his historical research. These practices included the reading, ordering, and comparison of textual sources. Moreover, Mach appropriated the historical-philological method of source criticism. I show that prominent fellow physicists of Mach, including Johann Poggendorff and Hermann von Helmholtz, made use of similar historical methods, even though their aims were different. Together, the cases of these history-writing physicists illustrate how history and natural science continued to intertwine in a time of increasing disciplinary fragmentation