Fire, as Gaston Bachelard observed, haunts the psychology of modern societies. Its psychological power can be traced deep into ancient mythologies. The Titan Prometheus, who stole fire from Olympus and gave it to humankind, is a popular hero of European memory. The romanticized public image of furnaces provided by classical mythology was reframed by their increasing use from the Middle Age onward, including in alchemy and industrialization. Thinking about how different cultures have represented heating technologies across millennia indicates that the history of the furnace, and the way it has been used, can reveal a great deal about scientific and technological imagery, the intellectual and manual labor that goes into manipulating materials, and the connection between practical know-how and theoretical knowledge. Yet, in spite of their scientific and economic importance in the twentieth century, furnaces have received little attention from science and technology studies (STS) scholars. Furnaces thus appear as invisible tools in the collective memory of materials. Yet, they are precisely the type of “things that talk” according to Lorraine Daston’s assertion “that things are simultaneously material and meaningful”. To give voice to high-temperature devices, let us follow briefly, first, some of their scientific and industrial developments during the twentieth century and, then, the role they played in the making of the US microelectronics industry in the 1950s.