We have seen, that after bringing together all the fragments the Hippocratic writers have transmitted to us, relative to the structure of the human body, it would be impossible to compose from them a regular or complete treatise on anatomy ; for, with the exception of the skeleton, they possessed very limited and imperfect notions of any organic apparatus. They confounded, under a common name, the
nerves, ligaments, and tendons ; they did not distinguish, or very imperfectly, the arteries and veins, and the muscles, in their eyes, were inert masses, designed solely to cover the bones, and serve as an envelope or an ornament. They possessed, in short, only gross and false ideas, on the structure and functions of the brain, heart, liver, lungs, digestive and generative apparatus - for the reason that they had never been able, as well remarks the author of the History of Anatomy, to devote themselves to regular dissections ; but this did not prevent them from adducing very decisive opinions on the organs and their functions, which no one could either verify or deny.
Let us now see what additions and what improvements the physicians of the following period conferred upon that state of the science. Galen is the sole author of that period, whose writings on anatomy and physiology have not entirely perished. We have several works of his on these subjects, which treat especially on these two branches, viz : First, a monograph on the Skeleton, in which he recommends that the bones be not studied in books only, but that they be seen and handled ; and to do that, he advises the student to go to Alexandria, where the professors, he says, will place before him the human skeleton. This advice of Galen proves, that in his time there was not in Rome a single skeleton, on which to demonstrate osteology. Secondly, a complete treatise on Anatomy, divided into fifteen books, of which six are wanting, entitled, On Anatomical Administration. Thirdly, an anatomo-physiological treatise on the Functions of the Regions of the human body - distributed in seventeen books, which we have entire. And finally, a quantity of anatomical and physiological details, scattered in various writings, which relate to other subjects. It is, then, from the writings of Galen, chiefly, that we draw what we have to say on the progress of anatomy and physiology, in the period extending from the foundation of the Alexandrian library, to the end of the second century of the Christian era.
From History of Medicine by P.V. Renouard M.D.