Blood Ties: Chemistry of the Body and Classifying Disease

Medical historians have thoroughly researched anatomical and physiological studies in the early modern period. By looking at the practices of eighteenth-century medical professors and students, I will address the question how chemical technologies altered ideas about the body. First, I will argue that bodily fluids as subject matter can trace developments of academic chemistry in medicine. Inspired by Jan Baptista van Helmont, Dutch chemists and physicians such as Herman Boerhaave and Jerome Gaub studied their patients’ blood, milk and urine. From the early eighteenth century onwards, medical students in Leiden and other Dutch universities increasingly applied chemical methods to bodily fluids to learn what the body consisted of. Second, I will argue that chemical examinations of bodily fluids ignited new ideas and theories about the body. Mechanics had explained the circulation of the blood. The coagulation of blood, by contrast, was a phenomenon that could only be examined chemically. Boerhaave proposed the existence of vital forces, because the process involved qualitative changes in active, living matter. In sum, focussing on new chemical experimentations at Dutch medical faculties will provide a new perspective on eighteenth-century physiology and pathology