Chapter 3, ‘The Mines and the Court’ is set both in the Ore Mountains and at the court of Dresden under August of Saxony (1553–1586). It offers a broader picture of the vibrant intellectual life in mining cities, illustrated here by the example of Annaberg. Local officials and technicians developed remarkable skills in arithmetic and geometry, on which rulers came to rely to map their realms and tame their capricious landscapes. I focus on the careers of two dynasties of practitioners, respectively subterranean surveyors (the Öders) and reckoning masters (the Rieses). After both patriarchs contributed to the economic rise of the city, their descendants became versatile engineers and courtiers of the Saxon Electors. They collaborated with university professors and instrument-makers, using their skills all over the Electorate and beyond, temporarily turning the court of Dresden into a centre of practical mathematics.

Chapter 5, ‘“So Fair a Subterraneous City”: Mapping the Underground’, focuses on map-making and the visualization of the underground. It argues that these developments were deeply linked to broad changes in the political structure of mining regions. Drawing mining maps and working on them became widespread in the second half of the seventeenth century, gradually replacing alternative tools such as written reports of visitations, wood models, or annotated sketches. In Saxony, Captain-general Abraham von Schönberg (1640–1711) put his weight and reputation behind the new cartographic technology, hoping that its acceptance would in turn help him advance his reform agenda. At-scale representations were instrumental in justifying new investments, while offering technical road maps to implement them. Johann Berger (1649–1695) spent years producing a monumental cartographic enterprise, the Freiberga subterranea (1693) to support his patron’s ambitions. As surveyors finally realized the old dream of ‘seeing through stones’, the administrations rapidly seized their skills to reform and police their subterraneous cities.