This book explores René Descartes s attempts to describe particular bodies, such as rocks, minerals, metals, plants, and animals, within the mechanistic interpretation of nature of his philosophical program. Despite his early rationalistic epistemology, Descartes s increasing attention to collections, histories, lists of qualities, and particular bodies results in a puzzling short history of all natural phenomenä contained in the Principles of philosophy (1644). The present book outlines the role of Descartes's observations and experimentation as he aimed to construct a universal science of nature, ultimately revealing the mechanization of nature in detail, and for curious bodies such as the Bologna Stone or the sensitive herb. What results is a theoretical natural history consistent with the mechanical principles of his philosophy, ultimately shedding new light on his attempt to produce a complete philosophy of nature.