How Solid is the Rock? Extraction of Workers’ Knowledge in 18th-Century Mining

This article examines a short book about »rock« (Gestein) written by the geologist and government offi­cial Abraham Gottlob Werner in 1788. Rock, in this case, was not an epistemic object in the emerging earth sciences, that studied fossils, minerals, and the formation of mountains. Instead, I argue that it was a concern for an early attempt at the scientific management of mines. Early-modern mining was expensive and technically challenging, and it was not always profitable. Therefore, scholar-officials like Werner looked for ways to employ less labour. In their search, they drew on workers’ knowledge, especially of the behaviour of underground rock. Thus, scholars transformed workers’ knowledge into a »science« (Wissenschaft) of mining work. Current models of early modern knowledge production engaging both scholars and practitioners, such as the trading zone and hybridization, do not adequately explain this transformation. I propose complementing these models with the notion of extraction. Scholar-officials extracted knowledge from workers, amalgamated it with other knowledge (such as mineralogy), and then reintroduced it to the workforce, not in the form of new theories, but as instructions for how to perform labour. Unlike in the trading zone and hybridization models, this process tended to reinforce, rather than weaken, the distinctions between different types of knowledge and different groups of knowers.