The Epistemic Elevation of Vegetable Commodities

1 Chemists grouping together of proximate principles of plants after 1750 

What counted as the most significant chemical components or principles of plants changed considerably around 1750. Whereas by 1700 chemists were almost exclusively concerned with the ultimate simple elements or principles of plants—apart from a few individual exceptions, such as Simon Boulduc—, after 1750 the majority of chemists became more interested in the compound components or proximate principles of plants. The increase in collective attention the compound components of plants received from 1750 on did not entirely replace the search for the ultimate principles of plants. Instead, chemists began to establish an order of analysis by distinguishing between two kinds of plant-chemical analysis first, the analysis of entire plants and the organized parts of plants, which aimed at separating the more compound or proximate principles of plants and, second, the further analysis of the proximate principles into their ultimate components or simple principles. Whereas the lat- 

1 Simon [2005] and Kim [2003] p. 212 have asserted that chemists pharmaceutical interests declined in the second half of the eighteenth century. At first glance, the change of chemists mode of classifying plant materials seems to evince that claim, but the following analysis will show that the development was more complex. 

Flolmes presented all later eighteenth-century plant analysis as the analysis of proximate principles of plants by means of solvents. Therefore we wish to emphasize that almost all eighteenth-century chemists we have studied actually also further analyzed the substances extracted fixrm plants by dry distillation. In so doing, many of them even tried to study the different proportions of the distillation products. Lavoisier s elemental analysis of plant and animal compounds continued to some extent an old tradition that was never given up when chemists became more interested in the proximate principles of plants. But Lavoisier also changed both the technique and the conceptual resources for analysis of the elemental composition of plant and animal substances. See also our explanations in chapter 14. 

Venel [1755]. For hfe and work of Venel, see Gillispie [1970-1980] vol. XIII p. 602ff. 

---