This paper studies European chemists’ shifting ontologies of materials by comparing the ways in which they classified materials. The focus is on plant materials, their different identities, and the changing ways chemists sorted out and ordered plant materials in the eighteenth and early nineteenth centuries. The main goals of the paper are to follow the development of plant materials from ordinary, everyday materials and commodities in the early eighteenth century to purified carbon compounds and organic substances familiar only to experts (...) in the 1830s, and to reconstruct chemists’ ways of classifying these objects in different practical and intellectual contexts.The study of changes in European chemists’ ways of classifying plant materials over more than a century brings to the foreground a trajectory of ontological shifts that is ‘punctuated’ in the 1750s, the 1790s, and the 1830s. Early eighteenth-century plant materials, which were commodities of the apothecary trade and other arts and crafts, were elevated epistemically as compound components or ‘proximate principles’ of plants in the 1750s, reduced to organic compounds in the 1790s, and replaced by carbon compounds in the 1830s. The last, third transformation of the epistemic constitution of materials and the mode of their classification was accompanied by a deep transformation of the material culture of plant chemistry. After the late 1830s, many of the eighteenth-century vegetable commodities disappeared from chemists’ agenda or were split into different substances individuated and identified in new ways. Coal tar products, and new organic artefacts containing chlorine or bromine, entered the chemical laboratory in the 1820s and became fused with the purified rest of the previous plant and animal substances. The material objects of the new culture of organic chemistry became detached from the materials applied in the extant arts and crafts. It was only in the late 1850s, with the rise of the synthetic dye industry, that a great number of these laboratory substances became involved in industrial production.Keywords: Commodities and scientific objects; Historical ontology; Classification; Plant chemistry; Organic chemistry. (shrink)

The appearance and proliferation of physics laboratories in the academic institutions of Britain between 1865 and 1885 is an established feature of Victorian science. However, neither of the two existing modern accounts of this development have adequately documented the predominant function of these early physics laboratories as centres for theteachingof physics, characteristically stressing instead the exceptional cases of the research laboratories at Glasgow and Cambridge. Hence these accounts have attempted to explain, somewhat misleadingly, the genesis of these laboratories purely by (...) reference to the stimuli of professionalizedresearchprogrammes, instead of considering the contemporary growth in demand for the professional laboratory teaching of physics. In failing to consider such physics laboratories in terms of the political economy of British education, these accounts have also faileda fortiorito correlate this development with the contemporaneous extension of laboratory teaching methods to other scientific disciplines, a movement dubbed as a laboratory ‘revolution’ by later nineteenth-century commentators. (shrink)