Page:The New International Encyclopædia 1st ed. v. 01.djvu/594

ANATOMY. section (Gk. avd, ana, apart + ri/iveiv. temnein, to cut), formerly the sole method of investiga- tion. It is distinguished as Human, Animal, or Plant Anatomy, according to the organisms under consideration; as Normal or Pathological Anato- my according as these are in health or diseased; as Macroscopic or Gross Anatomy when it deals with structure visible to the naked e.ye ; and as Microscopic or Minute Anatomy when the micro- scope is used as a means of research. This last division is often more aptly called General Anat- omy because of its generalization, or histology-, in view of the delicate webs of structure or tissues (lardc, histos, web) it investigates. Com- parative Anatomy involves a comparison of the different forms of animals and plants, and Devel- opmental Anatomy or Embryology an account of the different forms assumed by a single individual during its growth.

Other designations applied to anatomy have reference to its application. Dissection and the preparation of anatomical specimens is often called Practical Anatomy; the arrangement of the facts of structure according to their bearing upon the diagnosis and treatment of disorders is Applied Anatomy, which may be divided into Surgical Anatomy, that deals witlr structure accessible for surgical operations, and Medical Anatomy, that relates to structure which can be reached only indirectly. Physiological Anatomy gives the facts of structure that explain the function of organs ; Artistic or Plastic Anatomy gives such facts as may be useful to the artist or the sculptor; Plastic Anatomy is a term some- times used to designate the teaching of the science by means of artificial models composed of sepai"able parts. The consideration of the deeper relations and causes of structure is called Philosophical .Anatomy, or Morphology, and a purely speculative or theoretical disquisition of this kind is termed Transcendental Anatomy.

Anatomy may be treated in two different ways: as Descriptive or Systematic Anatomy, that arranges the facts of the science with reference to the structural affinities of organs forming the systems of the body, or as Topographical or Regional Anatoiny, that considers the organs merely with reference to their exact situation and relations to each other. Descriptive Anat- omy is usually subdivided into Osteology, that treats of the osseous system; Syndesmology, that treats of the ligaments; or Arthrology, that con- siders the ligaments and joints; Myology, that treats of the muscles ; Neurology, of the nerves ; Angeiology, of the vessels; Splanchnology, of the viscera. The knowledge of anatomy possessed by the ancients was slight. The importance of exact information not being generally recognized, and the dead body being held especially sacred, exam- ination of the cadaver was rare, and attended with great difficulties. It is among the Greeks that the first traces of the science are found. Hippocrates (460-300 B.C.) and his school appear to have had some knowledge of the skel- eton and cf the larger viscera; Aristotle (.384-323 B.C.) examined a large number of animals, and had some remarkably Jiist ideas as to their genetic relationships: Herophilus (c. 300 B.C.) and Rrasistratus of Alexandria investigated the vessels and the glandular organs. At the Alex- andrian School. dissection was first publicly prac- ticed, and there a considerable advance was made in the knowledge of tlie human body. Only frag- ments of the writings of this time have come down to us. Heropliilus described the sinuses of the dura mater, the retina, the lacteals, and the lymphatics, and admitted that the arteries contained blood, his predecessors having held that, like the air-tubes of the lungs, they normally carried air during life. Erasistratus considered the brain as an organ for the transformation of the "vital spirits" received from the air into "animal spirits," and distinguished between nerves of motion and those of sensation.

The prejudice against dissection appears to have flnalh' overcome the progress achieved by the Alexandrian School, and the belief became current that the healing art depended upon metaphysical conditions impossible to elucidate by an examination of structure. The next con- siderable advance was made by Claudius Galen (q.v.) of Pergamus (131-201 A.D.), who com- piled mucli from his predecessors, and was the author of the first systematic treatise that has come down to us. He appears to have examined apes rather than man, but correctly described most of the bones, joints, muscles, cranial and spinal nerves, and many features about the brain and its membranes. He performed a great ser- vice for anatomy Ijy clearly and exactly describ- ing what he had actually inspected and by re- cording his ob.servations in a methodical manner. These very merits, however, caused the almost universal acceptance of his erroneous physio- logical speculations, which gave rise to false ideas of the structure of the circulatory appara- tus that prevailed until the middle of the seven- teenth century. He taught that after digestion, food is carried to the liver by the portal vein, and there converted into crude blood having nutritive properties due to "natural spirits:" that from the liver it passes to the right side of the heart, where a portion enters the venous system, in which it ebbs and flows, affording nutrition to the bod.v, another portion passing through invisible pores in the septum of the heart to its left side, where it becomes mixed with air drawn in from the lungs by the pul- monary veins, and tluis receives the "vital spir- its," and is freed from impurities (fuliginous vapors) by the "innate heat" of the heart; thus vitalized and clarified, it passes into the arterial system, in which it also has a,n oscillatory mo- tion, endowing the body with the higher func- tions of life, while in the brain it is further elaborated to "animal spirits" that arc con- veyed throughout the body by the tubular nerves to impart movement.

The irruption of the northern barbarians arrested all attempts at scientific research, and it was not until after the renaissance of letters and science at the hands of the Arabs, who resuscitated the learning of the ancient Greeks, that further advances were nurde. At Salerno and Montpellier active medical schools were established, and some attempt was made to revive the study of anatomy. Frederick II., Emperor of Germany (1215-50), is said to have forbidden anyone to practice surgery without a competent knowledge of anatomy, and to have provided that every five years there should be held at Salerno a public dissection, to which physicians and surgeons from all parts of the Empire were invited. At Montpellier the cadavers of criminals were regularly dissected. The Senate of Venice decreed in 1308 that a human body should