Discover how chemical structure guides physiological action to prevent and cure disease, in the Croonian Lectures of 1889. This edition explains the links between molecules, metabolism, and treatment strategies. This nonfiction work presents a historical look at how the composition and arrangement of chemical substances relate to how the body responds. It covers the bridge between chemistry and medicine, showing how structure influences action in prevention, control, and cure of disease. How chemical structure affects the way drugs and remedies act in the body - The role of metabolism, oxidation and reduction in health and disease - Connections between microbes, poisons, and treatment approaches of the era - Examples of anesthetics, analgesics, and other therapeutic agents discussed through historical experiments Ideal for readers of medical history, pharmacology, and the development of chemical‑physiological thinking in late 19th century medicine.