Anatomy

Anatomy (Gr., 'a cutting up or dissecting') is the science of the form and structure of organised bodies, and is practically acquired by separation of the parts of a body, so as to show their distinct formation, and their relations to each other. It is therefore a branch of the science of Biology, which consists of two great divisions—the Anatomy of animals, styled Zootomy, and that of plants, Phytotomy. The various divisions of Anatomy will be found at the end of the following historical sketch.

History of Anatomy.—It is difficult to determine the date at which this science began to be cultivated, but it is probable that from the earliest times some persons took advantage of favourable circumstances to acquaint themselves with it. Alemæon of Crotona, a disciple of Pythagoras, and Democritus are said to have dissected animals with the view of obtaining comparative knowledge of human anatomy. Hippocrates (q.v.), born at Cos about 460 B.C., though the father of medicine, is less justly regarded as the father of anatomy, as his views of the structure of the human body are very superficial and incorrect. Aristotle, born 384 B.C., is really the founder of the science. He seems to have based his systematic views of comparative anatomy on the dissection of animals, but does not appear to have dissected men. He first gave the name aorta to the great artery. No real progress in human anatomy was made, owing to the researches being confined to animals, till the time of Erasistratus (250 B.C.), who was the first to dissect human bodies—the bodies of criminals. Herophilus also is said to have dissected living subjects. Celsus (63 B.C.) in his De Medicinâ wrote much on anatomy.

Galen (131 A.D.) dissected apes, as being most like human subjects, though he occasionally obtained bodies of persons found murdered; and his writings show a knowledge of human anatomy. Soranus, Oribasius, Nemesius, Meletius, and Theophilus based their anatomical works mainly on Galen. Anatomy made small progress among the Arabs, as their religion prohibited contact with dead bodies. Avicenna (980 A.D.), born in the province of Khorassan, was a good osteologist, and described some structures not alluded to by Galen.

The medical school at Bologna became famous in the 13th century, as did also those at Padua and Salerno; but no very material progress was made in anatomy. Mondino, born at Milan, 1315, professed anatomy there, and is considered the real restorer of anatomy in Italy. Then came Guy de Chauliac, Mathæus de Gradibus (1480), Gabriel de Zerbis (1495), Achillini (1512), Berenger of Carpi (1578), Etienne, Massa, and Sylvius (1539). An epoch is made by Andrew Vesalius (q.v.), who published a great work on anatomy before he was 28 years of age.

William Horman of Salisbury wrote, in 1530, Anatomia Corporis Humani. Thomas Gemini of London, in 1545, engraved upon copper the anatomical figures of Vesalius, which had appeared in Germany upon wood. Gemini suppressed the name of Vesalius, though using his figures and descriptions. Thomas Vicary, in 1548, is said to be the first who wrote in English on anatomy; he published The Englishman's Treasure, or the True Anatomy of Man's Body. Franco (1556), Valverda, and Colunibus wrote works of great merit on anatomy. In 1561 Gabriel Fallopius (q.v.) taught with great distinction at Padua, and made many original discoveries.

In the 17th century, progress was rapid. Harvey, in 1619, discovered the circulation of the blood, and the microscope was employed to detect the structure of minute vessels. Aselli, in 1622, discovered and demonstrated the existence of the lymph-vessels. The glandular organs were investigated by Wharton, while Malpighi, Swammerdam, and the illustrious Ruysch, by the use of injections and the aid of the microscope, gave a new impulse to research in the minute structures. Eminent names in the history of anatomy are numerous in the 18th century. In Italy, which still retained its former pre-eminence, we find Pacchioni, Valsalva, Morgagni, Santorini, Mascagni, and Cotunni; in France, Winslow, D'Aubenton, Lieutaud, Vicq d'Azyr, and Bichât, the founder of general anatomy; in Germany, Haller and Meckel prepared the way for greater achievements in the 19th century; in Great Britain, Cowper, Cheselden, Hunter, Cruikshank, Monro, and Charles Bell contributed to the progress of the science; while Holland was worthily represented by Boerhaave, Albinus, Camper, Sandifort, and Bonn. On the boundaries of the two centuries, we find the names of Sommering, Loder, Blumenbach, Hildebrand, Reil, Tiedemann, and Seiler.

The necessity of a union of theory and practice has led to the study of PATHOLOGICAL ANATOMY (the dissection and study of structures as modified by diseases). The origin of this branch of anatomy may be traced back to ancient times in Egypt; and amongst the Greeks some anatomico-pathological observations are found. During the general revival of science in the 16th century, many notices of pathological anatomy occur. Morgagni (1767) must, however, be regarded as the true founder of Pathological Anatomy. He was worthily followed by Lieutaud, Sandifort, Hunter, Baillie, Meckel the younger, and others. The recent change of direction given to the study of Pathological Anatomy, which is now properly regarded as a means towards practical improvements in medicine, must be ascribed to Bichât and the pupils of Broussais, among whom may be mentioned the names of Laennec, Cruveilhier, Louis, Andral, Lobstein, Lebert, Virchow, and Bennett.

Theoretical anatomy is divided into General and Special. GENERAL ANATOMY gives a description of the elementary tissues of which the systems and organs of the body are composed, as preliminary to an examination of them in their combined state in the various organs: it also investigates their laws of formation and combination, and the changes which they undergo in various stages of life. This branch of study may also be styled Structural or Analytical Anatomy, and has been first developed in recent times, especially by Bichât (1801) and Beclard, who have been followed by J. Müller, Goodsir, Henle, E. H. Weber, Schwann, Valentin, and many others. In our day, microscopic investigation has been successfully applied to the study of elementary textures. See HISTOLOGY.

SPECIAL ANATOMY (styled Descriptive by the French writers) treats of the several parts and organs of the body in respect to their form, structure, and systematic connection or relation with each other. The arrangement of the several parts and organs in an order deduced from their similarity in structure or use, constitutes SYSTEMATIC ANATOMY. According to this mode of study, which is essential as an introduction to physiology, anatomy has been divided, though not with scientific precision, into six branches of study. 1. Osteology, which treats of the bones, including the cartilages of the joints (chondrology). 2. Arthrology, which describes the ligaments, or bands, that unite the bones of various joints. The bones, with their cartilages and ligaments, form a framework, which supports the external soft parts, and within which the vital organs are suspended and protected from injury; they are also arranged in a mechanical system as organs of locomotion. 3. Myology explains the system of the muscles, which, by their contractile power, serve to impart motion to the bones and joints; while, like the bones, they contribute to form the cavities of the body, and to protect the internal organs. Their form also serves to produce the external shape and symmetry. 4. Angiology describes the vessels or ducts, with their complex network and ramifications, spreading over most parts of the body, and divided into two great systems: (a) the blood-vessels with the heart, a fleshy organ propelling the blood through the pulsating vessels or arteries, from which it returns to the heart, after circulation through the veins; (b) the lymphatics, by means of which a certain fluid (lymph) is passed through a series of organs named lymphatic glands, and afterwards enters the large veins at the root of the neck. The lacteals, which absorb the chyle from the intestine, also belong to this system of vessels. 5. Neurology, or the doctrine of the nerves, describes the nervous system, as divided into, first, the two central masses of the brain and the spinal cord; second, the ramifications of nerves running from the brain and spinal cord to almost all points of the surface; and lastly, the order of nerves having a peculiar structure, and styled the ganglionic system of nerves. 6. Splanchnology describes the viscera or organs formed by combination of the distinct systems of veins, nerves, lymphatics, &c., and mostly situated in the cavities of the body. These are divided into five groups—viz.: (a) the organs of the senses—sight, hearing, smell, taste, and touch; (b) of voice and respiration—nostrils, mouth, larynx, trachea, and lungs, with the thyroid gland, the thymus gland, and the diaphragm; (c) digestive organs—the mouth, with its salivary glands, the throat, gullet, the stomach, the intestines, with the liver, spleen, and pancreas; (d) the urinary organs—kidneys, ureters, bladder, and urethra; (e) sexual organs of both sexes.

Special anatomy may be treated in another mode; by an arrangement made in accordance with natural divisions, or by imaginary lines dividing the body into several regions—as the head, the trunk, and the extremities. Again, the trunk may be subdivided into neck, thorax, and abdomen; and in each of the main regions, several subdivisions may be made. This system of arrangement may be styled Topographical Anatomy, and is also known as Surgical Anatomy, on account of its importance as the basis of operative surgery. It was the eldest of the Monros of Edinburgh University who first gave this branch of the study its due prominence.

COMPARATIVE ANATOMY, the investigation and comparison of the structures of two or more animals, has always preceded anthropotomy, or dissection of the human subject, but was first treated systematically as a distinct science by Cuvier and his pupil, Meckel the younger. Blumenbach, Tiedemann, Home, Blainville, Geoffroy St Hilaire, Carus, Oken, Goethe, Owen, Goodsir, Müller, Wagner, Siebold, Bowman, Todd, Milne-Edwards, Von Baer, Gegenbaur, Kölliker, Remak, Czermak, Leydig, Frey, Schwann, Haeckel, Kovalovsky, Agassiz, Van Beneden, Burmeister, Carpenter, Allman, Sharpey, Allen Thomson, Huxley, Turner, and Flower, may be named as eminent contributors to this branch of science.

ANATOMY FOR ARTISTS is studied with reference to the effects produced by internal structure on the external form, and describes the organs, especially the muscles and tendons, not only in a state of rest, but also as modified by passion, action, and posture.

PRACTICAL ANATOMY includes Dissection (q.v.) and the making of Preparations. Preparation consists in dividing parts or organs, so that their respective forms and positions may be clearly shown. Organs or parts thus treated are styled Anatomical Preparations of bones, muscles, vessels, nerves, &c. For example, a bone-preparation is made by clearing away all muscular and other adhesions; the whole structure of the bones, thus prepared and bleached, when connected by wires in its natural order, forms an artificial skeleton. Preparations of the soft parts are either dried and varnished or preserved in spirit.

A series of such specimens, arranged in proper order, forms an Anatomical Museum. The valuable collections made by Ruysch, Rau, Loder, Walter, John and William Hunter, Meckel, Sömmering, Dupuytren, and Goodsir, are all now public property. As it is impossible to preserve thus all parts in their integrity for any great length of time, artificial copies in wood, ivory, papier-mâché, and wax are made with great exactitude. But, apart from dissections and preparations of the natural organs, the most general and available assistance in the study of anatomy is found in anatomical engravings and plates on wood and copper. This assistance was known in ancient times. Aristotle affixed to his works on anatomy some anatomical drawings, which have been lost. In the 16th century the greatest artists—Leonardo da Vinci, Michael Angelo, Raphael, Titian, and Dürer—gave their aid in designing anatomical figures. Lately, lithography has been employed. See works by Langenbeck (1826), Arnold (1833, 5th ed. 1865), Meckel (1817–1826), Cruveilhier (1841), Froriep (1828), Hyrtl (16th ed. 1882), Malgaigne (1859); in Comparative Anatomy, Carus, Wagner, Cuvier, Gegenbaur, Milne Edwards, Owen, Huxley. Among English works may be mentioned those by Lizars, Jones, Cooper, Richard Quain, Ellis, and Ford, in Special Anatomy; by Morton and Mælsie, in Surgical Anatomy; and by Baillie and Bright in Pathological Anatomy.

The anatomy of the various parts and organs of the body will be found described, frequently in conjunction with their physiology, under their proper heads. Among the more important articles are the following: