ANATOMY(Ανατομή) means in its literal sense the dissection or separation of parts by cutting, but in its usual acceptation it is employed to denote the science the province of which is to determine the construction, the form, and the structure of organised bodies, i.e., of bodies which either are or have been living. It is therefore a department of the science of Biology. It resolves itself into two great divisions— Animal Anatomy or Zootomy, the object of which is to investigate the structure of animals; and Vegetable Anatomy or Phytotomy, the object of which is to elucidate the structure of plants. As Vegetable Anatomy will be treated of in the article Botany, it does not require to be considered here. Animal Anatomy, again, naturally resolves itself into two divisions: one in which the construction, form, and structure of two or more animals are compared with each other, so as to bring out their features of resemblance or dissimilarity,—this is called Comparative Anatomy; the other, in which the construction, form, and structure of parts in a single animal are considered, which is termed Special Anatomy. The special anatomy of an animal may be studied from various points of view: (a) with reference to the succession of forme which it exhibits at various periods from its first appearance as an embryo to the assumption of its adult characters; this is termed Developmental or Embryological Anatomy; (b) with reference either to its form and structure, or to the investigation of the laws by which these are determined, termed Morphological Anatomy; (c) with reference to the function, use, or purpose performed by a part or structure in an animal, termed Teleological or Physiological Anatomy; (d) with reference merely to the relative position of different parts or ...structures, termed Topographical Anatomy; (e) with reference to the structure and general properties of the tissues or textures which enter into the construction of the parts or organs of animals; to th⅛ branch of study have been applied the terms General Anatomy, Anatomy op Textures, Histology, and, from the microscope being so largely employed in the examination of the textures, Microscopic or Minute Anatomy; (f) with reference to the changes induced by disease in the organs or tissues, termed Morbid or Pathologicae Anatomy. From its manifold aspects anatomy forms the basis of the Biological Sciences. As a knowledge of the laws of motion is essential, and must be constantly recurred to at every step before any true progress can be made in the investigation of the physical sciences, so must the structure of animal bodies be constantly appealed to by the zoologist in all attempts at classification; by the physiologist in all inquiries into the functions performed by the organs and textures in a state of health, and into the special adaptation of parts to particular uses; and by the physician in considering the alterations or disturbance of the functions of parts in the course of disease. To describe the anatomy of the multitudinous forms of animal life from these different points of view would require, not one, but several voluminous treatises, and would much exceed the compass of a single article. Moreover, it is advisable that the anatomy of the different classes of the animal kingdom should be considered under their respective heads,—e.y., that of the Crabs under Crustacea, that of Reptiles under Reptilia, &c. It is intended to devote this article more particularly to the description of the Special Anatomy of the Human Body in a state of health; in other words, to make it a short treatise on Human Anatomy or Anthro-potomy, which, as forming a department of the general science of Comparative Anatomy, is interesting not only to men of science generally, but, from its intimate connnection with the several divisions of the art of healing, and with the study of the functions of the human body, possesses the highest importance to the physician, surgeon, and physiologist.
Previous to entering on the consideration of the Anatomy of the Human Body, it may be well to take a historical view of the progress of the science from its origin to the present time.
HISTORY OF ANATOMY.
In tracing the history of the origin of anatomy, it may be justly said that more learning than judgment has been displayed. Some writers claim for it the highest antiquity, and pretend to find its first rudiments alternately in the animal sacrifices of the shepherd kings, the Jews, and other ancient nations, and in the art of embalming as practised by the Egyptian *priests, Even the descriptions of wounds in the Iliad have been supposed adequate to prove that in the time of Homer mankind had distinct notions of the structure of the human body. Of the first it may be said that the rude information obtained by the slaughter of animals for sacrifice does not imply profound anatomical knowledge; and those who adduce the second as evidence are deceived by the language of the poet of the Trojan war, which, distinguishing certain parts by their ordinary Greek epithets, as afterwards used by Hippocrates, Galen, and all anatomists, has been rather too easily supposed to prove that the poet had studied systematically the structure of the human frame.
With not much greater justice has the cultivation of anatomical knowledge been ascribed to Hippocrates, who, because he is universally allowed to be the father of medicine, has also been thought to be the creator of the science of anatomy. Of the seven individuals of the family of the Heracleidae who bore this celebrated name, the second, who was son of Heraclides and Phenarita, and grandson of the first Hippocrates, was indeed distinguished as a , physician of great observation and experience, and the first who appreciated the value of studying accurately the phenomena, effects, and terminations of disease. It does not appear, however, notwithstanding the vague and general panegyrics of Riolan, Bartholin, Le Clerc, and Portal, that the anatomical knowledge of this illustrious person was either accurate or profound. Of the works ascribed to Hippocrates, five only are genuine. Most of them were written either by subsequent authors of the same name, or by one or other of the numerous impostors who took advantage of the zealous munificence of the Ptolemies, by fabricating works under that illustrious name. Of the few which are genuine, there is none expressly devoted to anatomy; and of his knowledge on this subject the only proofs are to be found in the exposition of his physiological opinions, and his medical or surgical instructions. From these it appears that Hippocrates had some accurate notions on osteology, but that of the structure of the human body in general his ideas were at once superficial and erroneous. In his book on injuries of the head, and in that on fractures, he shows that he knew the sutures of the cranium and the relative situation of the bones, and that he had some notion of the shape of the bones in general, and of their mutual connections. Of the muscles, of the soft parts in general, and of the internal organs, his ideas are confused, indistinct, and erroneous. The term φλeβ<s he seems, in imitation of the colloquial Greek, to have used generally to signify a blood-vessel, without being aware of the distinction of vein and artery; and the term αρτηρία, or air-holder, is restricted to the windpipe. He appears to have been unaware of the existence of the nervous chords; and the term nerve is used by him, as by Grecian authors in general, to signify a sinew or tendon. On other, points his views are so much combined with peculiar physiological doctrines, that it is impossible to assign them the character of anatomical facts; and even the works in which these doctrines are contained are with little probability to be ascribed to the second Hippocrates. If, however, we overlook this difficulty, and admit what is contained in the genuine Hippocratic writings to represent at least the sum of knowledge possessed by Hippocrates and his immediate descendants, we find that he represents the brain as a gland, from which exudes a viscid fluid; that the heart is muscular and of pyramidal shape, and has two ventricles separated by a partition, the fountains of life—and two auricles, receptacles of air; that the lungs consist of five ash-coloured lobes, the substance of which is cellular and spongy, naturally dry, but refreshed by the air; and that the kidneys are glands, but possess an attractive faculty, by virtue of which the moisture of the drink is separated, and descends into the bladder. He distinguishes the bowels into colon and rectum (ô αpχos).
The knowledge possessed by the second Hippocrates was transmitted in various degrees of purity to the descendants and pupils, chiefly of the family of the Heracleidøe, who succeeded him. Several of these, with feelings of grateful affection, appear to have studied to preserve the written memory of his instructions, and in this manner to. have contributed to form part of that collection of treatises which have long been known to the learned world under the general name of the Hippocratic writings. Though composed, like the genuine remains of the physician of Cos, in the Ionian dialect, all of them differ from these in being more diffuse in style, more elaborate in form, and in studying to invest their anatomical and medical matter with the fanciful ornaments of the Platonic philosophy. Hippocrates had the merit of early recognising the value of facts apart from opinions, and of those facts especially which lead to general results; and in the few genuine writings which are now extant it is easy to perceive that he has recourse to the simplest language, expresses himself in terms which, though short and pithy, are always precise and perspicuous, and is averse to the introduction of philosophical dogmas. Of the greater part of the writings collected under his name, on the contrary, the general character is verboseness, prolixity, and a great tendency to speculative opinions. For these reasons, as well as for others derived from internal evidence, while the Aphorisms, the Epidemics, and the works above mentioned, bear distinct marks of being the genuine remains of Hippocrates, it is impossible to regard the book πep ∖ Φwγlo<s Ανθρωπον as entirely the composition of that physician; and it appears more reasonable to view it as the work of some one of the numerous disciples to whom the author had communicated the results of his observation, which they unwisely attempted to combine with the philosophy of the Platonic school and their own mysterious opinions.
Among those who aimed at this distinction, the most fortunate in the preservation of his name is Polybus, the son-in-law of the physician of Cos. This person, who must not be confounded with the monarch of Corinth immortalised by Sophocles in the tragic story of Oedipus, is represented as a recluse, severed from the world and its enjoyments, and devoting himself to the study of anatomy and physiology, and to the composition of works on these subjects. To him has been ascribed the whole of the book on the Nature of the Child and most of that On Man; both physiological treatises interspersed with anatomic^ sketches. His anatomical information, with which wt are specially concerned, appears to have been rude and inaccurate, like that of his preceptor. He represents the large vessels of the body as consisting of four pairs; the first proceeding from the head by the back of the neck and spinal chord to the hips, lower extremities, and outer ankle; the second, consisting of the jugular vessels (αi σφaγiτιδες), proceeding to the loins, thighs, hams, and inner ankle; the third proceeding from the temples by the neck to the scapula and lungs, and thence by mutual intercrossings to the spleen and left kidney, and the liver and right kidney, and finally to the rectum; and the fourth from the forepart of the neck to the upper extremities, the fore-part of the trunk, and the organs of generation.
This specimen of the anatomical knowledge of one of the most illustrious of the Hippocratic disciples differs not essentially from that of Syennesis, the physician of Cyprus, and Diogenes, the philosopher of Apollonia, two authors for the preservation of whose opinions we are indebted to Aristotle. They may be admitted as representing the state of anatomical knowledge among the most enlightened men at that time, and they only show how rude and erroneous were their ideas on the structure of the animal body. It may indeed, without injustice, be said that the anatomy of the Hippocratic school is not only erroneous, but fanciful and imaginary, in often substituting mere supposition and assertion for what ought to be matter of fact. From this censure it is impossible to exempt even the name of Plato himself, for whom some notices in the Timaeus on the structure of the animal body, as taught by Hippocrates and Polybus, have procured a place in the history of the science.
Amidst, the general obscurity in which the early history of anatomy is involved, only two leading facts may be admitted with certainty. The first is, that previous to the time of Aristotle there was no accurate knowledge of anatomy; and the second, that all that was known was derived from the dissection of the lower animals ’ only. By the appearance of Aristotle this species of knowledge, which was hitherto acquired in a desultory and irregular manner, began to be cultivated systematically and with a definite object; and among the services which the philosopher of Stagira rendered to mankind, one of the greatest and most substantial is, that he was the founder of Comparative Anatomy, and was the first to apply its facts to the elucidation of zoology. The works of this ardent and original naturalist show that his zootomical knowledge was extensive and often accurate; and from several of his descriptions it is impossible to doubt that they were derived from frequent personal dissection. Aristotle, who was born 384 years before the Christian era, or in the first year of the 99th Olympiad, was, at the age of 39, requested by Philip to undertake the education of his son Alexander. During this period it is said he composed several works on anatomy, which, however, are now lost. The military expedition of his royal pupil into Asia, by laying open the animal stores of that vast and little known continent, furnished Aristotle with the means of extending his knowledge, not only of the animal tribes, but of their structure, and of communicating more accurate and distinct notions than were yet accessible to the world. A sum of 800 talents, and the concurrent aid of numerous intelligent assistants in Greece and Asia, were intended to facilitate his researches in composing a system of zoological knowledge; but it has been observed that the number of instances in which he was thus compelled to trust to the testimony of other observers led him to commit errors in description which personal observation might have enabled him to avoid.
The first three books of the History of Animals, a treatise consisting of ten books, and the four books on the Parts of Animals, constitute the great monument of the Aristotelian Anatomy. From these we find that Aristotle was the first who corrected the erroneous statements of Polybus, Syennesis, and Diogenes regarding the bloodvessels, which they made, as we have seen, to arise from the head and brain. These he represents to be two in number, placed before the spinal column, the larger on the right, the smaller on the left, which, he also remarks, is by some called αoriα (αορτή), the first time we observe that this epithet occurs in the history. Both he represents to arise from the heart, the larger from the largest upper cavity, the smaller or aorta from the middle cavity, but in a different manner and forming a narrower canal. He also distinguishes the thick, firm, and more tendinous structure of the aorta from the thin and membranous structure of vein. In describing the distribution of the latter, however, he confounds the vena cava and pulmonary artery, and, as might be expected, he confounds the ramifications of the former with those of the arterial tubes in general. While he represents the lung to be liberally supplied with blood, he describes the brain as an organ almost destitute of this fluid. His account of the distribution of the aorta is wonderfully correct. Though he does not notice the coeliac, and remarks that the aorta sends no direct branches to the liver and spleen, he had observed the mesenteric, the renal, and the common iliac arteries. It is nevertheless singular that though he remarks particularly that the renal branches of the aorta go to the substance and not the pelvis (κοιλία) of the kidney, he appears to mistake the ureters for branches of the aorta. Of the nerves (νεύρα) he appears to have the most confused notions. Making them arise from the heart, which he says has nerves (tendons) in its largest cavity, he represents the aorta to be a nervous or tendinous vein (νευρώδης φλεβς). By and by, afterwards saying that all the articulated bones are connected by nerves, he makes them the same as ligaments.
He distinguishes the windpipe or air-holder (αρτηρία) from the oesophagus, because it is placed before the latter, because food or drink passing into it causes distressing cough and suffocation, and because there is no passage from the lung to the stomach. He knew the situation and use of the epiglottis, seems to have had some indistinct notions of the larynx, represents the windpipe to be necessary to convey air to and from the lungs, and appears to have a tolerable understanding of the structure of the lungs. He repeatedly represents the heart, the shape and site of which he describes accurately, to be the origin of the blood-vessels, in opposition to those who made them descend from the head; yet, though he represents it as full of blood and the source and fountain of that fluid, and even speaks of the blood flowing from the heart to the veins, and thence to every part of the body, he says nothing of the circular motion of the blood. The diaphragm he distinguishes by the name διάζωμα, and υπόζωμα. With the liver and spleen, and the whole alimentary canal, he seems well acquainted. The several parts of the quadruple stomach of the ruminating animals are distinguished and named; and he even traces the relations between the teeth and the several forms of stomach, and the length or brevity, the simplicity or complication, of the intestinal tube. Upon the same principle he distinguishes the jejunum (η vηστις), or the empty portion of the small intestines in animals (το εvτεpov λεπτόν), the caecum (τυφλόν τι και ογκώδες), the colon (το κώλον), and the sigmoid flexure (στεvurτεpov καϊ εiλιγμεvov). The modern epithet of rectum is the literal translation of his description of the straight progress (ευθύ) of the bowel to the anus (ποωκτός). He knew the nasal cavities and the passage from the tympanal cavity of the ear to the palate, afterwards described by Eustachius. He distinguishes as “partes similares” those structures, such as bone, cartilage, vessels, sinews, blood, lymph, fat, flesh, which, not confined to one locality, but distributed throughout the body generally, we now term the tissues or textures, whilst he applies the term “partes dissimilares” to the regions of the head, neck, trunk, and extremities.
Next to Aristotle occur the names of Diodes of Carystus, and Praxagoras of Cos, the last of the family of the Asclepiadae. The latter is remarkable for being the first who distinguished the arteries from the veins, and the author of the opinion that the former were air-vessels.
Hitherto anatomical inquiry was confined to the examination of the bodies of brute animals. We have, indeed, no testimony of the human body being submitted to exam in a-tion previous to the time of Erasistratus and Herophilus; and it is vain to look for authentic facts on this point before the foundation of the Ptolemaic dynasty of sovereigns in Egypt. This event, which, as is generally known, succeeded the death of Alexander, 320 years before the Christian era, collected into one spot the scattered embers of literature and science, which were beginning to languish in Greece under a weak and distracted government and an unsettled state of society. The children of her divided states, whom domestic discord and the uncertainties of war rendered unhappy at home, wandered into Egypt, and found, under the fostering hand of the Alexandrian monarchs, the means of cultivating the sciences, and repaying with interest to the country of Thoth and Osiris the benefits which had been conferred on the infancy of Greece by Thales and Pythagoras. Alexandria became in this manner the repository of all the learning and knowledge of the civilised world; and while other nations were sinking under...
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