De Humani Corporis Fabrica Libri Septem (Latin, lit. "On the fabric of the human body in seven books") is a set of books on human anatomy written by Andreas Vesalius (1514–1564) and published in 1543. It was a major advance in the history of anatomy over the long-dominant work of Galen, and presented itself as such. The collection of books is based on his Paduan lectures, during which he deviated from common practice by dissecting a corpse to illustrate what he was discussing. Dissections had previously been performed by a barber surgeon under the direction of a doctor of medicine, who was not expected to perform manual labour. Vesalius's magnum opus presents a careful examination of the organs and the complete structure of the human body. This would not have been possible without the many advances that had been made during the Renaissance, including artistic developments in literal visual representation and the technical development of printing with refined woodcut engravings. Because of these developments and his careful, immediate involvement, Vesalius was able to produce illustrations superior to any produced previously. Books of the collection Vesalius arranged his work into seven books. Book 1: The Bones and Cartilages The first book constitutes about a quarter of the entire collection. It presents Vesalius' observations on human bones and cartilage, which he collected from cemeteries. It covers the physical appearance of human bones and the differentiation of human bones and cartilage by function. In each chapter Vesalius describes the bones in great detail, explaining their physical qualities in different ways. In the opening chapters, Vesalius "gives general aspects of bones and skeletal organisation, dealing with the differences in texture, strength, and resilience between bone and cartilage; explaining the complex differences between types of joints and reviewing some basic elements of descriptive techniques and terminology." A major theme of this book is whether Galen described the bones of the human skeleton accurately. When Vesalius lectured on the human skeleton, he also presented the bones of animals to give credibility to Galen's observations. Book 2: The Ligaments and Muscles Here Vesalius describes the structure of the muscles, the agents used in creating movement by the body, and the material used to hold the joints together. Through his observations of butchers cutting meat, he was able to incorporate the skills they used in the dissection of the human body. The order in which to dissect a