Mining knowledge: Nineteenth-century Cornish electrical science and the controversies of clay.

Michael Faraday's laboratory experiments have dominated traditional histories of the electrical sciences in 1820s and 1830s Britain. However, as this article demonstrates, in the mining region of Cornwall, Robert Were Fox fashioned a very different approach to the study of electromagnetic phenomena. Here, it was the mine that provided the foremost site of scientific experimentation, with Fox employing these underground locations to measure the Earth's heat and make claims over the existence of subterranean electrical currents. Yet securing philosophical claims cultivated in mines proved challenging for Fox, with metropolitan audiences, including Faraday, loath to give credit to the results of these underground experiments. This article explores how Fox developed a way of modeling his mine experiments, using clay samples, to communicate knowledge from industrial Cornwall to urban centers of elite science. It argues that the mine was an epistemologically complex venue of scientific activity, at once seeming to provide a way of examining nature directly, without recourse to laboratory contrivance, while simultaneously being a place where knowledge claims were hard to verify without access to these physically challenging locations. In exploring Fox's work, this study contributes to a growing literature of spatial investigation that takes the vertical as its unit of analysis.