The Historical Furnace as Assemblage: Space, Circulation, and Early Modern Fire Management

When Rudolph Glauber (1604-1670) announced a new chymical furnace in the late 1640s, he emphasised its ability to reach very high temperatures - without the aid of bellows - thanks to a cleverly engineered structure. This pyrotechnically innovative furnace marks a clear shift in early modern furnace design. In this article, we argue that Glauber's furnace was more than an isolated technological advance. Rather, his structural approach to furnace design emerged from a complex history of heat engineering, pressures of fuel scarcity, and ideas about the circulation of wind, air, heat, and smoke. By looking at his apparatus alongside pyrotechnical developments in the domestic sphere, we argue that the furnace was never merely a fire in a box, but rather forms an assemblage with the surrounding architecture and beyond. This broader view of the furnace allows us to further probe and historicise the early modern pyroscape and to reassess the role of chymistry within it.