‘The soil is the laboratory in which the food [of the plants] is prepared.’
(Humphry Davy, 1813)
In the mid-eighteenth century, chemists started to explore and describe agricultural processes in terms of chemical methods and principles. The utilitarianism of Enlightenment thought in Europe and North America incited these chemists to package their knowledge as both useful and practical, which in turn helped them to gain public recognition and acceptance. To avoid being labeled mere theorists, they had to leave their laboratory buildings to study the farmer's field. They undertook individual experiments in pots and performed medium-sized cultivation trials in gardens and greenhouses. Some of them, such as Johann Gottschalk Wallerius and William Cullen, carried out trials on their own farms. Others like the instructor Heinrich Einhof at the Agricultural Academy in Möglin, Germany used land owned by educational institutions to pursue their inquiries. Engaging with other like-minded philosophers, big landowners, and farmers in the widespread Republic of Letters, chemists even had different types of plants and soil samples sent to them. These chemists not only brought their view of nature to bear on agriculture, they also brought chemical instruments and reagents from the laboratory to the field. For example, in 1805 Humphry Davy developed a suitable kit for outdoor soil analyses. Overall, this paper explores how chemists transformed the conception of a field as a place of toil and unpredictable produce to a space of precise and practical chemical inquiry. The farmer’s field had become a viable laboratory.
