Historians of science and historians of technology have recently turned their attention to the conceptual history of "applied science" and "technology" respectively. "Technology" was a concept introduced in the nineteenth century as concerning both "applied science" and "industrial arts." A developed version of this concept caught on after the first decades of the twentieth century, following the establishment of technological networks and the rise of "Fordism," "Taylorism" and "technocracy." Based on interpretations of the nineteenth-century circuit of the steam engine and the twentieth-century network of electric power, this chapter brings together observations from the history of science, the history of technology and the critique of classic political economy to elaborate on the suggestion that "technology" has been a "hazardous' concept. Central to the argument of the chapter is the retrieval of a correspondence between the conceptual couples "technology"-"technics' and 'surplus value"-"value."