Historians of eighteenth-century chemistry have traditionally focused on British and French works leading to Lavoisier's chemical revolution. German and Swedish contributions have hitherto been seen as empirical rather than theoretical, since these mainly consisted in the isolation of new elements and the classification of minerals by means of analytic criteria. The Limits of Matter challenges this view. Fors claims that mechanical philosophy and economic cameralism – a political doctrine linking domestic mining enterprises to the state – dramatically changed the epistemological status and the practice of chemistry in eighteenth-century Europe. Such a claim is based on a discerning study of ‘the social construction of metals as metallic elements’ and the refusal of what Fors describes as ‘centrist historiographic accounts’ of early modern chemistry (pp. 6, 9). Focusing on the works of the affiliates to the Bureau of Mines of Stockholm, the book challenges the older scholarship's emphasis on the role of the Freiberg Mining School for the emergence of scientific mining. In Fors's narrative the Swedish Bureau offers a privileged point of view on Enlightenment chemistry. The book describes how the bureau created a ‘contact zone’ among socially distinct chemical and mineralogical practitioners. In such a new social context, the passage from chymistry to modern chemistry and chemical mineralogy took the shape of a parting of ways of two research communities, whose networks, practices and epistemology diverged.

From Urban Hiärne to Axel Friedrik Cronstedt, Swedish chemists and natural philosophers at the bureau were part of a wide European network. Chemical philosophy was institutionalized in the mining bureaucracy of the Swedish state thanks to the efforts of Hiärne and his assistant and disciple Erich Odhelius. Although he still pursued alchemical researches in his Laboratorium Chemicum, Hiärne contributed to the marginalization of miners’ superstitious beliefs in the existence of demons and trolls of the underground. A great contribution to the renovation of Swedish chemistry came from the transfer of knowledge following the return of many mining officials sent by the bureau to the rest of Europe. During a sojourn in the mining districts of the Holy Roman Empire and in England, Odhelius rejected chrysopoeia and embraced the new experimental philosophy. After the death of Odhelius and Hiärne, the Laboratorium chemicum languished. To revive it, in 1727 the bureau chose Georg Brandt, an Uppsala alumnus and former student of Boerhaave in Leiden. Brandt proved decisive in reshaping the bureau's agenda in the early decades of the eighteenth century. Aiming to transform chemistry into a mathematical discipline, like Newtonian physics, he provided seminal contributions towards the chemical identification of metals. Building on a positive evaluation of the extent and relevance of the links with the European scientific and mining community, Fors concludes that the notion of Swedish chemistry is misleading. The bureau's chemists appropriated new philosophical ideas, i.e. experimental and mechanical philosophy, and practices from the rest of the Continent. Their contribution to early modern chemistry, therefore, should be rather seen as part of a wider process of knowledge exchange and cultural interaction in Europe. The two main institutions producing chemical knowledge within the boundaries of the Swedish state, the bureau and Uppsala University, took part in this process. Throughout the eighteenth century the links between these institutions strengthened. Many graduates from Uppsala began their careers as state administrators in the bureau. This was the case for Emanuel Swedenborg. Long before his spiritualist turn in 1744, Swedenborg was a mining official of the bureau. As a student in Uppsala, he was influenced by the Cartesian and Leibnizian ideas circulating among the members of the College of the Curious. This informal college was led by Eric Benzelius, librarian and uncle of Swedenborg. For this reason Swedenborg became the assistant of Christopher Polhammar, who created a Laboratorium mechanicum modelled on Hiärne's Laboratorium chemicum. The career of Axel Fredrik Cronstedt began in similar terms. He was in fact a student of Wallerius in Uppsala and of Brandt in Stockholm.

Reconstructing the social and cultural background of the bureau's chemists, Fors shows how the political aim of this institution influenced its main scientific outcomes. Scientific mining and analytic chemistry produced saleable goods. Inasmuch as they were the solid and tangible constituents of the material world, the metals identified as basic species of nature were also commodities that could be bought and sold on the market. However, the role of mechanical philosophy in this process seems questionable. Throughout the book, the mechanical philosophy is considered just part of an ideology committed to the rationalization and commodification of nature. Ironically, though, the book itself provides enough evidence of the Swedish chemists’ lack of interest in theoretical questions, including mechanical theories, favouring a more practical approach consonant with the state's cameralistic policies. Mapping the social dynamics within and around the Bureau of Mines in eighteenth-century Sweden, The Limits of Matter contributes to a new image of Enlightenment chemistry.