M. R. Columbus and Gabriele Falloppio were pupils of Vesalius, the 16th century anatomist, regarded by many as the founder of the science. Columbus, as his immediate successor in Padua, and afterwards professor at Rome, distinguished himself by rectifying and improving the anatomy of the bones; by giving correct accounts of the shape and cavities of the heart, of the pulmonary artery and aorta and their valves, and tracing the course of the blood from the right to the left side of the heart; by a good description of the brain and its vessels, and by correct understanding of the internal ear, and the first good account of the ventricles of the larynx. Osteology nearly at the same time found an assiduous cultivator in Giovanni Filippo Ingrassias
The anatomical descriptions of Vesalius underwent the scrutiny of various inquirers, notably Julius Caesar Aranzi.
Italy, though rich in anatomical talent, has probably few greater names than that of Constantio Varoli or Varollus. Among the anatomists of the Italian school, as a pupil of Fallopius, Eustachius and U. Aldrovandus, is generally enumerated Volcher Coiter (b. 1534) of Groningen. He distinguished himself by accurate researches on the cartilages, the bones and the nerves, recognized the value of morbid anatomy, and made experiments on living animals to ascertain the action of the heart and the influence of the brain.
The Frutefull and Necessary Brief Worke of John Halle (1565) and The Englisheman's Treasure by Master Thomas Vicary (1586), English works published at this time, are tolerable compilations from authors much influenced by Galenian and Arabian distinctions. A more valuable compendium than either is, however, that of John Banister (1578), entitled The Historie of Man, from the most approved Anathomistes in this Present Age.
The importance of the anatomical school of Italy was maintained by Hieronymus Fabricius of Acquapendente, who, in imitation of his master Fallopius, laboured to render anatomical knowledge more precise by repeated dissections, and to illustrate the obscure by researches on the structure of animals in general, and discovered the "membranous folds" (valves) in the interior of veins. Several of these folds had been observed by Fernel, Sylvius and Vesalius; and in 1547 G. B. Canani observed those of the vena azygos; but no one appears to have offered any rational conjecture on their use, or to have traced them through the venous system at large, until Fabricius in 1574, upon this hypothesis, demonstrated the presence of these valvular folds in all the veins of the extremities.
Fabricius, though succeeded by his pupil Julius Casserius of Placenza, was the last of the illustrious line of anatomical teachers by whom the science was so successfully advanced in the universities of Italy. Their discoveries, and the errors which their successive labours rectified, gradually gave anatomy the character of a useful as well as an accurate science, and paved the way for a discovery which, though not anatomical but physiological, is so intimately connected with correct anatomical knowledge that it exercised a powerful influence on the future progress of the science. This was the knowledge of the circular motion of the blood--a fact which though obscurely conjectured by Aristotle, Nemesius, Mondino and Berenger, and partially taught by Servetus, Columbus, Andreas Caesalpinus and Fabricius, it was nevertheless reserved to William Harvey fully and satisfactorily to demonstrate.
Mondino believed that the blood proceeds from the heart to the lungs through the vena arterialis or pulmonary artery, and that the aorta conveys the spirit into the blood through all parts of the body. This doctrine was adopted with little modification by Berenger, who further demonstrated the existence and operation of the tricuspid valves in the right ventricle, and of the sigmoid valves at the beginning of the pulmonary artery and aorta, and that there were only two ventricles separated by a solid impervious septum. These were afterwards described in greater detail by Vesalius, who nevertheless appears not to have been aware of the important use which might be made of this knowledge.
A Spanish theologian, Michael Servetus (born in 1509, burnt as a heretic in 1553), used his treatise De Trinitatis Erroribus, published at Haguenau in 1531, to maintain the imperviousness of the septum, and the transition of the blood by what he terms an unknown route, namely, from the right ventricle by the vena arteriosa (pulmonary artery) to the lungs, and thence into the arteria venosa or pulmonary vein and left auricle and ventricle, from which, he adds afterwards, it is conveyed by the aorta to all parts of the body.
Though the leading outlines, not only of the pulmonary or small but even of the great circulation, were sketched thus early by one who, though a philosopher, was attached to the church, it was only in Columbus's work De Re Anatomica, published at Venice in 1559, that the circular course of the blood was announced as a discovery; he maintained, in addition to the imperviousness of the septum, the fact that the arteria venalis (pulmonary vein) contains, not air, but blood mixed with air brought from the lungs to the left ventricle of the heart, to be distributed through the body at large.
Soon after, views still more complete of the small or pulmonary circulation were given by Andreas Caesalpinus (1519-1603) of Arezzo, who maintained the analogy between the structure of the arterious vein or pulmonary artery and the aorta, and that between the venous artery or pulmonary veins and veins in general, and was the first to notice the swelling of veins below ligatures, and to infer from it a refluent motion of blood in these vessels. The discoveries of Aranzi and Eustachius in the vessels of the foetus tended at first to perplex and afterwards to elucidate some of these notions.
Between 1598 and 1600, a young Englishman, William Harvey, pursuing his anatomical studies at Padua under Fabricius, learned about the existence of the valves in the veins of the extremities, and undertook to ascertain the use of these valves by experiment. It is uncertain whether he learnt from the writings of Caesalpinus the fact of the tumescence of a vein below the ligature, but he was aware of the small circulation as taught by Servetus and Columbus. Combining these facts already known, he, by a series of well-executed experiments, demonstrated clearly the existence, not only of the small, but of a general circulation from the left side of the heart by the aorta and its subdivisions, to the right side by the veins. This memorable truth was first announced in the year 1619.
Harvey was forced to defend his controversial theory against all comers. However, the doctrine of the circular motion of the blood was soon admitted by all enlightened and unprejudiced persons, and finally was universally adopted as affording the most satisfactory explanation of many facts in anatomical structure which were either misunderstood or entirely overlooked. The inquiries to which the investigation of the doctrine gave rise produced numerous researches on the shape and structure of the heart and its divisions, of the lungs, and of the blood-vessels and their distribution. Of this description were the researches of Nicolas Steno on the structure of the heart, the classical work of Richard Lower, the dissertation of J. N. Pechlin, the treatise of Raymond Vieussens, the work of Marcello Malpighi on the structure of the lungs, several sketches in the writings of John Mayow, and other less important treatises. Systematic treatises of anatomy began to assume a more instructive form, and to breathe a more philosophical spirit. The great work of Adrian Spigelius, which appeared in 1627, two years after his death, contains no proof that he was aware of Harvey's work; but in the institutions of Caspar Bartholinus, republished and improved by his son Thomas in 1651, the anatomical descriptions and explanations are given with reference to the new doctrine. Further proof of progress was given in the lectures delivered by Peter Dionis, at the Jardin Royal of Paris, in 1673 and the seven following years, in which he gave accurate demonstrations of all the parts composing the human frame, and especially of the heart, its auricles, ventricles and valves, and the large vessels connected with it and the lungs. These demonstrations, first published in 1690, were so highly regarded that they passed through seven editions in thirty years, and were translated into English.
The progress of anatomical discovery continued to advance. Eustachius, in studying minutely the structure of the vena azygos, had recognized in the horse a white vessel full of watery fluid, connected with the internal jugular vein, on the left side of the vertebral column, corresponding accurately with the vessel since named thoracic duct. Fallopius also described vessels belonging to the liver distinct from arteries and veins; and similar vessels appear to have been noticed by Nicolaus Massa (1499-1569). The nature and properties of these vessels were entirely unknown. On July 23, 1622 Gaspar Aselli, professor of anatomy at Pavia, while engaged in demonstrating the recurrent nerves in a living dog, first observed numerous white delicate filaments crossing the mesentery in all directions; and though he took them at first for nerves, the opaque white fluid which they shed quickly convinced him that they were a new order of vessels. The repetition of the experiment the following day showed that these vessels were best seen in animals recently fed; and as he traced them from the villous membrane of the intestines, and observed the valves with which they were liberally supplied, he inferred that they were genuine chyliferous vessels. By confounding them with the lymphatics, he made them proceed to the pancreas and liver--a mistake which appears to have been first rectified by Francis de le Boe. Aselli's discovery was announced in 1627; and the following year, by means of the zealous efforts of Nicolas Peiresc, a liberal senator of Aix, the vessels were seen in the person of a felon who had eaten copiously before execution, and whose body was inspected an hour and a half after. In 1629 they were publicly demonstrated at Copenhagen by Simon Pauli, and the same year the thoracic duct was observed by Jacques Mentel (1599-1670) for the first time since it was described by Eustachius. Five years after (1634), John Wesling, professor of anatomy and surgery at Venice, gave the first delineation of the lacteals from the human subject, and evinced more accurate knowledge than his predecessors of the thoracic duct and the lymphatics. Nathaniel Highmore (1613-1685), a physician practising at Sherborne all his life, in 1637 demonstrated unequivocally the difference between the lacteals and the mesenteric veins; and though some perplexity was occasioned by the discovery of the pancreatic duct by Christopher Wirsung, this mistake was corrected by Thomas Bartholinus; and the discovery by Jean Pecquet in 1647 of the common trunk of the lacteals and lymphatics, and of the course which the chyle follows to reach the blood, may be regarded as the last of the series of isolated facts by the generalization of which the extent, distribution and uses of the most important organs of the animal body were at length developed.
To complete the history of this part of anatomical science one step yet remained--the distinction between the lacteals and lymphatics, and the discovery of the termination of the latter order of vessels. This discovery was made jointly by George Joyliffe (1621-1658), an English anatomist, and Olaus Rudbeck (1630-1702), a young Swede. Joyliffe, according to the testimony of Francis Glisson and Thomas Wharton, was aware of the distinct existence of the lymphatics in 1650, and demonstrated them as such in 1652. It is nevertheless doubtful whether he knew them much before the latter period; and it is certain that Rudbeck observed the lymphatics of the large intestines, and traced them to glands, on 27 January, 1651, after he had, in the course of 1650, made various erroneous conjectures regarding them, and, like others, attempted to trace them to the liver. The following year he demonstrated them in presence of Queen Christina, and traced them to the thoracic duct, and the latter to the subclavian vein. Their course and distribution were still more fully investigated by Thomas Bartholinus, Wharton, J. Swammerdam and G. Blaes, the last two of whom recognized the existence of valves; while Antony Nuck of Leiden rectified various errors of his predecessors, and added several new and valuable observations.
After this period anatomists began to study more minutely the organs and textures. Francis Glisson, for forty years professor of physic at Cambridge, provided a minute description of the liver (1654) and a clearer account of the stomach and intestines than had yet been given. Thomas Wharton, graduate both of Oxford and Cambridge, and physician to St Thomas's Hospital, investigated the structure of the glands with particular care; and though rather prone to indulge in fanciful generalization, he developed some interesting views of these organs; while Walter Charleton (1619-1707), though addicted to hypothesis, observed the communication of the arteries with the veins, the foetal circulation and the course of the lymphatics.
The circumstance which chiefly distinguished the history of anatomy at the beginning of the 17th century was the appearance of Thomas Willis (1621-1675), Sedleian professor of natural philosophy in Oxford in 1660, who rendered himself eminent not only by good researches on the brain and nerves, but by many judicious observations on the structure of the lungs, the intestines, the blood-vessels and the glands.
About the middle of the 17th century R. Hooke and Nehemiah Grew employed the simple microscope in the minute examination of plants and animals; and the Dutch philosopher A. Leeuwenhoek with great acuteness examined microscopically the solids and fluids of the body, recognized the presence of scales in the cuticle, and discovered the corpuscles in the blood and milk, and the spermatozoa in the seminal fluid. The researches of Marcello Malpighi also tended greatly to improve the knowledge of minute structure. He gave the first distinct ideas on the organization of the lung, and the mode in which the bronchial tubes and vessels terminate in that organ. By the microscope he traced the transition of the arteries into the veins, and saw the movements of the blood corpuscles in the capillaries. He endeavoured to unfold, by dissection and microscopic observation, the minute structure of the brain. He studied the structure of bone, he traced the formation and explained the structure of the teeth; and his name is to this day associated with the discovery of the deeper layer of the cuticle and the Malpighian bodies in the spleen and kidney. In these difficult inquiries the observations of Malpighi are in general faithful, and he may be regarded as the founder of histological anatomy.
Nicolas Steno, or Stensen, described with accuracy (1660) the lacrymal gland and passages, and rediscovered the parotid duct. L. Bellini studied the structure of the kidneys, and described the tongue and tonsils with some care; and Charles Drelincourt laboured to investigate the changes effected on the uterus by impregnation, and to elucidate the formation of the foetus. The science might have derived still greater advantages from the genius of Regnier de Graaf, who investigated with accuracy the structure of the pancreas and of the organs of generation in both sexes, had he not died at the age of thirty-two. Lastly, Wepfer, though more devoted to morbid anatomy, made, nevertheless, some just observations on the anatomical disposition of the cerebral vessels, the glandular structure of the liver, and the termination of the common duct in the duodenum.
The appearance of Frederic Ruysch, (1638-1731) professor of anatomy at Amsterdam from 1665, gave a new impulse to anatomical research, and tended not only to give the science greater precision, but to extend its limits in every direction. The talents of Ruysch are said to have been developed by accident. To repel the audacious and calumnious aspersions with which Louis de Bils attacked de le Boe and van Horne, Ruysch published his tract on the valves of the lymphatics, which completely established his character as an anatomist of originality and research. This is the smallest of his services to the science. The art of injecting, which had been originally attempted by Eustachi and Varoli, and was afterwards rudely practised by Glisson, Bellini and Willis, was carried to greater perfection by de Graaf and Swammerdam, the former of whom injected the spermatic vessels with mercury and variously coloured liquors; while the latter, by employing melted wax with other ingredients, made the first approach to the refinements of modern anatomy. By improving this idea of using substances which, though solid, may be rendered fluid at the period of injecting, Ruysch carried this art to the highest perfection.
This enabled him to demonstrate the arrangement of minute vessels in the interior of organs which had escaped the scrutiny of previous anatomists. Scarcely a part of the human body eluded the penetration of his syringe; and his discoveries were proportionally great. His account of the valves of the lymphatics, of the vessels of the lungs, and their minute structure; his researches on the vascular structure of the skin, of the bones, and their epiphyses, and their mode of growth and union; his observations on the spleen, the glans penis, the clitoris, and the womb impregnated and unimpregnated, were but a limited part of his anatomical labours. He studied the minute structure of the brain; he demonstrated the organization of the choroid plexus; he described the state of the hair when affected with Polish plait; he proved the vascular structure of the teeth; he injected the dura mater, the pleura, the pericardium and peritoneum; he unfolded the minute structure of the conglomerate glands; he investigated that of the synovial apparatus placed in the interior of the joints; and he discovered additional facts about the lacteals, the lymphatics and the lymphatic glands.
Meanwhile, H. Meibomius rediscovered (1670) the palpebral glands, which were known to Casserius; Swammerdam studied the action of the lungs, described the structure of the human uterus, and made numerous valuable observations on the coeca and pancreatoid organs of fishes; and Th. Kerckring laid the foundation of a knowledge of the process of ossification. John Conrad Brunner, in the course of experiments on the pancreas, discovered (1687) the glands of the duodenum named after him, and J. Conrad Peyer (1677-1681) described the solitary and agminated glands of the intestinal canal. Leonard Tassin, distinguished for original observation, rendered the anatomical history of the brain more accurate than heretofore, and gave particular accounts of the intestinal tube, the pancreatic duct and the hepatic ligaments (1678).
That France might not be without participation in the glory of advancing the progress of anatomical knowledge, the names of Joseph Guichard Duverney and Vieussens are commemorated with distinction. Duverney, born in 1648, and first introduced into public life in 1676 in the Royal Academy of Sciences, decorated with the honorary title of professor of anatomy to the dauphin, and appointed in 1679 professor at the Jardin Royal, distinguished himself by the first accurate account of the organ of hearing, and by his dissections of several animals at the academy supplied valuable materials for the anatomical details of the natural history of animals published by that learned body. He appears to have been the first who demonstrated the fact that the cerebral sinuses open into the jugular veins, and to have been aware that the former receives the veins of the brain and are the venous receptacles of the organ. He understood the cerebral cavities and their mode of communication; distinguishes the posterior pillars of the vault from the pedes hippocampi; recognizes the two plates of the septum lucidum; and, what is still more remarkable, he first indicates distinctly the discussation of the anterior pyramids of the medulla oblongata--a fact afterwards verified by the researches of Mistichelli, F. P. du Petit and G.D. Santorini. He studied the ganglions attentively, and gives the first distinct account of the formation, connexions and distribution of the intercostal nerves. It is interesting to remark that his statement that the veins or sinuses of the spinal cord terminate in the vena azygos was verified by the subsequent researches of G. Dupuytren (1777-1835) and G. Breschet (1784-1845), which showed that the vertebral veins communicate by means of the intercostal and superior lumbar veins with the azygos and hemi-azygos. His account of the structure of bones and of the progress of ossification is valuable. He recognized the vascular structure of the spleen, and described the excretory ducts of the prostate gland, the verumontanum, and the anteprostates.
One of the circumstances which at this time tended considerably to the improvement of anatomical science was the attention with which Comparative Anatomy was beginning to be cultivated. In ancient times, and at the revival of letters, the dissection of the lower animals was substituted for that of the human body; and the descriptions of the organs of the latter were too often derived from the former. The obloquy and contempt in which this abuse involved the study of animal anatomy caused it to be neglected, or pursued with indifference, for more than two centuries, during which anatomists confined their descriptions, at least very much, to the parts of the human body. At this period, however, the prejudice against Comparative Anatomy began to subside; and animal dissection, though not substituted for that of the human body, was employed, as it ought always to have been, to illustrate obscurities, to determine doubts and to explain difficulties, and, in short, to enlarge and rectify the knowledge of the structure of animal bodies generally.
For this revolution in its favour, Comparative Anatomy was in a great measure indebted to the learned societies which were established about this time in the different countries of Europe. Among these, the Royal Society of London, embodied by charter by King Charles II of England in 1662, and the Academy of Sciences of Paris, founded in 1666 by Jean-Baptiste Colbert, are undoubtedly entitled to the first rank. Though later in establishment, the latter institution was distinguished by making the first great efforts in favour of Comparative Anatomy; and Claude Perrault, Pecquet, Duverney and Jean Mery, by the dissections of rare animals obtained from the royal menagerie, speedily supplied valuable materials for the anatomical naturalist.
In England, Nehemiah Grew, Edward Tyson (a graduate both of Oxford and Cambridge and reader of anatomy at Surgeons' Hall, London) and Samuel Collins (an M.D. of Padua, Oxford and Cambridge and physician in ordinary to Charles II) cultivated the same department with diligence and success. Grew has left an interesting account of the anatomical peculiarities of the intestinal canal in various animals; Tyson, in the dissection of a porpoise, an opossum and an orang outang, adduces some valuable illustrations of the comparative differences between the structure of the human body and that of the lower animals; Collins has the merit of conceiving, and executing on an enlarged plan, a comprehensive system, embodying all the information then extant (1685). With the aid of Tyson and his own researches, which were both extensive and accurate, he composed a system of anatomical knowledge in which he not only gives ample and accurate descriptions of the structure of the human body, and the various morbid changes to which the organs are liable, but illustrates the whole by accurate and interesting sketches of the peculiarities of the lower animals. The matter of this work is so excellent that it can only be ascribed to ignorance that it has received so little attention. Though regarded as a compilation, and though indeed much of the human anatomy is derived from Vesalius, it has the advantage of the works published on the continent at that time, that it embodies most of the valuable facts derived from Malpighi, Willis and Vieussens. The Comparative Anatomy is almost all original, the result of personal research and dissection; and the pathological observations, though occasionally tinged with the spirit of the times, show the author to have been endowed with the powers of observation and judicious reflexion in no ordinary degree.
About this time also we recognize the first attempts to study the minute constitution of the tissues, by the combination of the microscope and the effects of chemical agents. Bone furnished the first instance in which this method was put in use; and though Gagliardi, who undertook the inquiry, had fallen into some mistakes which it required the observation of Malpighi to rectify, this did not deter London physicians Clopton Havers (died 1702), and Robert Nesbitt (died 1761), who studied at Leiden. Courtial, H. L. Duhamel-Dumonceau and Delasone, and afterwards Herissant, in France, resumed the same train of investigation. The mistakes into which these anatomists fell belong to the imperfect method of inquiry. The facts which they ascertained have been verified by recent experiment, and constitute no unessential part of our knowledge of the structure of bone.
Ten years after the publication of the work of Collins, Humphrey Ridley (1653-1708), a London physician who studied at Leiden, distinguished himself by a monograph (1695) on the brain, which, though not free from errors, contains, nevertheless, some valuable observations. Ridley was the first to distinguish by name the restiform processes, or the posterior pyramidal eminences. He recognized the figure of the four eminences in the human subject; he remarked the mammillary bodies; and he discovered the sinus which passes under his name.
Raymond Vieussens, by the publication of his great work on neurography in 1684, threw new light on the configuration and structure of the brain, the spinal cord and the nerves; and gave a description of the arrangement and distribution of the latter more precise than heretofore. Of the formation and connexions of the sympathetic nerve especially he gave views which have been generally adopted by subsequent anatomists. His new arrangement of the vessels was published in 1705. His observations on the structure of the heart, published in 1706, and enlarged in 1715, exhibit the first correct views of the intimate structure of an organ which afterwards was most fully developed by the labours of G. M. Lancisi and J. B. Senac.
To the same period (1685-1697) belong the rival publications of G. Bidloo, a Dutch anatomist, and Wilham Cowper, a London surgeon, the latter of whom, however, stained a reputation otherwise good by publishing as his own the engravings of the former. Cowper further distinguished himself by a minute account of the urethral glands, already known to Columbus and Mery; by a good description of the intestinal glands, discovered by Brunner and Peyer; and by demonstrating the communication of the arteries and veins of the mesentery.
The anatomical reputation of Italy was revived by Lancisi, A. M. Valsalva, and his illustrious pupils G. D. Santorini and J. B. Morgagni. Valsalva especially distinguished himself by his description of the structure of the ear, which, in possessing still greater precision and minuteness than that of Duverney, is valuable in setting the example of rendering anatomy altogether a science of description.
Santorini, who was professor at Venice, made observations relating to the muscles of the face, the brain and several of the nerves, the ducts of the lachrymal gland, the nose and its cavities, the larynx, the viscera of the chest and belly, and the organs of generation in the two sexes. His essays were models of perspicuity, precision and novelty. and bear comparison with any anatomical writings which have appeared since.
Morgagni, though chiefly known as a pathological anatomist, did not neglect the healthy structure. His Adversaria, which appeared between 1706 and 1719, and his Epistles, published in 1728, contain a series of observations to rectify the mistakes of previous anatomists, and to determine the characters of the healthy structure of many parts of the human body. Many parts he describes anew, and indicates facts not previously observed. All his remarks show how well he knew what true anatomical description ought to be. In this respect, indeed, the three anatomists now mentioned may be said to have anticipated their contemporaries nearly a century; for, while other authors were satisfied with giving loose and inaccurate or meagre notices of parts, with much fanciful supposition, Valsalva, Santorini and Morgagni laboured to determine with precision the anatomical characters of the parts which they describe.
The same character is due to J.-B. Winslow (1669-1760), a native of Denmark, but, as pupil and successor of Duverney, as well as a convert to Catholicism, naturalized in France, and finally professor of anatomy at the Royal Gardens. His exposition of the structure of the human body is distinguished for being not only the first treatise of descriptive anatomy, divested of physiological details and hypothetical explanations foreign to the subject, but for being a close description derived from actual objects, without reference to the writings of previous anatomists. About the same time W. Cheselden in London, the first Alexander Monro in Edinburgh, and B. S. Albinus in Leiden, contributed by their several treatises to render anatomy still more precise as a descriptive science. The Osteographia of the first-mentioned was of much use in directing attention to the study of the skeleton and the morbid changes to which it is liable.
This work, however, magnificent as it was, was excelled by that of Albinus, who in 1747 published engravings, by Jan Wandelaar (1691-1759), of the bones and muscles, which had never been surpassed in accuracy of outline or beauty of execution. Albinus's career was an important era in the history of the science. He was the first to classify and exhibit the muscles in a proper arrangement, and applied to them a nomenclature which is still retained by the consent of the best anatomists. He gives a luminous account of the arteries and veins of the intestines, represents with singular fidelity and beauty the bones of the foetus, inquires into the structure of the skin and the cause of its colour in different races; represents the changes incident to the womb in different periods of pregnancy, and describes the relations of the thoracic duct and the vena azygos with the contiguous parts. Besides these large and magnificent works, illustrated by the most beautiful engravings, six books of Academical Annotations were the fruits of his long and assiduous cultivation of anatomy. These contain valuable remarks on the second structure and morbid deviations of numerous parts of the human body.
Albinus found a worthy successor in his pupil Albrecht von Haller (1708-1777), who, with extensive knowledge of literature and science, concentrated chiefly on anatomy and physiology. Having undertaken at an early age (twenty-one) to illustrate, with commentaries, the physiological prelections of his preceptor H. Boerhaave, he devoted himself assiduously to the perusal of every work which could tend to facilitate his purpose; and, as he found numerous erroneous or imperfect statements, and many deficiencies to supply, he undertook an extensive course of dissection of human and animal bodies to obtain the requisite information. During the seventeen years he was professor at Gottingen, he dissected 400 bodies, and inspected their organs with the utmost care. The result of these assiduous labours appeared at intervals in the form of dissertations by himself, or under the name of some one of his pupils, finally published in a collected shape between 1746 and 1751 (Disputationes Anatomicae Selectiores), and in eight numbers of most accurate and beautiful engravings, representing the most important parts of the human body, e.g. the diaphragm, the uterus, ovaries and vagina, the arteries of the different regions and organs, with learned and critical explanatory observations. He verified the observations that in the foetus the testicles lie in the abdomen, and showed that their descent into the scrotum may be complicated with the formation of congenital hernia. Some years after, when he had retired from his academical duties at Göttingen, he published between 1757 and 1765 the large and elaborate work called Elements of Physiology. This work, though professedly devoted to physiology, nevertheless, did great service to anatomy. Haller, drawing an accurate line of distinction between the two, gave the most clear, precise and complete descriptions of the situation, position, figure, component parts and minute structure of the different organs and their appendages. The results of previous and coeval inquiry, obtained by extensive reading, he sedulously verified by personal observation; and though he never rejected facts stated on credible authorities, he in all cases laboured to ascertain their real value by experiment. The anatomical descriptions are on this account not only the most valuable part of his work, but the most valuable that had then or for a long time after appeared. It is painful, nevertheless, to think that the very form in which this work is composed, with copious and scrupulous reference to authorities, made it be regarded as a compilation only; and that the author was compelled to show, by a list of his personal researches, that the most learned work ever given to the physiologist was also the most abundant in original information.
With the researches of Haller it is proper to notice those of his contemporaries, John Frederick Meckel, J. N. Lieberkuhn, and his pupil John Godfrey Zinn. The first, who was professor of anatomy at Berlin, described the Casserian ganglion, the first pair of nerves and its distribution and that of the facial nerves generally, and discovered the spheno-palatine ganglion (1748-1751). He made some original and judicious observations on the tissue of the skin and the mucous net (1753-1757); and above all, he recognized the connexion of the lymphatic vessels with the veins--a doctrine which, after long neglect, was revived by Vincent Fohmann (1794-1837) and Lippi. He also collected several valuable observations on the morbid states of the heart and brain. Lieberkuhn published in 1745 a dissertation on the villi and glands of the small intestines. Zinn, who was professor of medicine at Gottingen, published a classical treatise on the eye (1755), which demonstrated at once the defects of previous inquiries, and how much it was possible to elucidate, by accurate research and precise description, the structure of one of the most important organs of the human frame. It was republished after his death by H. A. Wrisberg (1780). About the same time J. Weitbrecht gave a copious and minute account of the ligaments, and J. Lieutaud (1703-1780), who had already laboured to rectify many errors in anatomy, described with care the structure and relations of the heart and its cavities, and rendered the anatomy of the bladder very precise, by describing the triangular space and the mammillary eminence at its neck.
The study of the minute anatomy of the tissues, originally begun by Leeuwenhoek, Malpighi and Ruysch, started to attract more general attention. Karl August von Bergen had already demonstrated (1732) the general distribution of cellular membrane, and showed that it not only incloses every part of the animal frame, but forms the basis of every organ--a doctrine which was adopted and still more fully expanded (1757) by his friend Haller, in opposition to what was asserted by Albinus, who maintains that each part has a proper tissue. William Hunter also gave a clear and ingenious statement of the difference between cellular membrane and adipose tissue (1757), in which he maintained the general distribution of the former, and represented it as forming the serous membranes, and regulating their physiological and pathological properties--doctrines which were afterwards confirmed by his brother John Hunter.
A few years after, the department of general anatomy first assumed a substantial form in the systematic view of the membranes and their mutual connexions traced by Andrew Bonn of Amsterdam. In his inaugural dissertation De Continuationibus Membranarum, published at Leiden in 1763, this author, after some preliminary observations on membranes in general and their structure, and an exposition of that of the skin, traces its transition into the mucous membranes and their several divisions. He then explains the distribution of the cellular membrane, the aponeurotic expansions, and the periosteum and perichondrium, by either of which, he shows, every bone of the skeleton is invested and connected. He finally gives a very distinct view of the arrangement of the internal membranes of cavities, those named serous and fibro-serous, and the manner of their distribution over the contained organs. This essay, which is a happy example of generalization, is remarkable for the interesting general views of the structure of the animal body which it exhibits; and to Bonn belongs the merit of sketching the first outlines of that system which it was reserved for the genius of M. F. X. Bichat to complete and embellish. Lastly, T. de Bordeu, in an elaborate essay (1767) on the mucous tissue, or celluar organ, as he terms it, brought forward some interesting views of the constitution, nature and extent of the cellular membrane.
Though anatomy had met with much success in illustrating the natural history and morbid states of the human body, little had been done for the elucidation of local diseases, and the surgical means by which they may be successfully treated. The idea of applying anatomical knowledge directly to this puroose appears to have originated with Bernardin Genga, a Roman surgeon, who published in 1672, at Rome, a work entitled Surgical Anatomy, or the Anatomical History of the Bones and Muscles of the Human Body, with the Description of the Blood- vessels. This work, which reached a second edition in 1687, is highly creditable to the author, who appears to have studied intimately the mutual relations of different parts. It is not improbable that the example of Genga led J. Palfyn, a surgeon at Ghent, to undertake a similar task about thirty years after (1718- 1726). For this, however, he was by no means well qualified; and the work of Palfyn, though bearing the name of Surgical Anatomy, is a miserable compilation, meagre in details, inaccurate in description, and altogether unworthy of the honour of being republished, as it afterwards was by Antony Petit.
While these two authors, however, were usefully employed in showing what was wanted for the surgeon, others were occupied in the collection of new and more accurate facts. Albinus, indeed, ever assiduous, had, in his account of the operations of Rau, given some good sketches of the relative anatomy of the bladder and urethra; and Cheselden had already, in his mode of cutting into the urinary bladder, shown the necessity of an exact knowledge of the relations of contiguous parts. The first decided application, however, of this species of anatomical research it was reserved for a Dutch anatomist of the 18th century to make.
Peter Camper, professor of anatomy at Amsterdam, published in 1760 and 1762 his anatomico-pathological demonstrations of the parts of the human arm and pelvis, of the diseases incident to them, and the mode of relieving them by operation, and explained with great clearness the situation of the blood-vessels, nerves and important muscles. His remarks on the lateral operation of lithotomy, which contain all that was then known on the subject, are exceedingly interesting and valuable to the surgeon. It appears, further, that he was the first who examined anatomically the mechanism of ruptures, his delineations of which were published in 1801 by S. T. Sommerring. Camper also wrote some important memoirs on Comparative Anatomy, and he was the author of a well-known work on the Relations of Anatomy to the Fine Arts.
The attention of anatomists was now directed to the elucidation of the most obscure and least explored parts of the human frame--the lymphatic vessels and the nerves. Although, since the first discovery of the former by Aselli, Rudbeck and Pecquet. much had been done, especially by Ruysch, Nuck, Meckel and Haller, many points, notwithstanding, relating to their origin and distribution in particular organs, and in the several classes of animals, were imperfectly ascertained or entirely unknown. William Hunter investigated their arrangement, and proposed the doctrine that they are absorbents; and John Hunter, who undertook to demonstrate the truth of this hypothesis by experiment, discovered, in 1758, lymphatics in the neck in birds.
As the doctrine required the existence of this order of vessels, not only in quadrupeds and birds but in reptiles and fishes, the inquiry attracted attention among the pupils of Hunter; and William Hewson, who was a partner with William Hunter in the Windmill Street School of Anatomy, at length communicated, in December 1768, to the Royal Society of London an account of the lacteals and lymphatics in birds, fishes and reptiles, as he had discovered and demonstrated them. The subject was about the same time investigated by the second Alexander Monro, who indeed claimed the merit of discovering these vessels in the classes of animals now mentioned. But whatever researches this anatomist may have instituted, Hewson, by communicating his observations to the Royal Society, must be allowed to possess the strongest as well as the clearest claim to discovery. The same author, in 1774, gave the first complete account of the anatomical peculiarities of the lymphatic system in man and other animals, and thereby supplied an important gap in this department. Hewson is the first who distinguishes the lymphatics into two orders--the superficial and the deep--both in the extremities and in the internal organs. He also studied the structure of the intestinal villi, in which he verified the observations of Lieberkuhn; and he made many important observations on the corpuscles of the lymph and blood. He finally applied his anatomical discoveries to explain many of the physiological and pathological phenomena of the animal body. Ten years after, John Sheldon, another pupil of Hunter, gave a second history and description of the lymphatics, which, though divested of the charm of novelty, contains many interesting anatomical facts. He also examined the structure of the villi.
Lastly, in 1786, Cruikshank, who followed W. Hunter as lecturer at the Windmill Street school, published a valuable history of the anatomy of the lymphatic system, in which he maintains the accuracy of the Hunterian doctrine, that the lymphatics are the only absorbents; gave a more minute account than heretofore of these vessels, of their coats and valves; and explained the structure of the lymphatic glands. He also injected the villi, and examined them microscopically, verifying most of the observations of Lieberkuhn. The origin of the lymphatics he maintains rather by inference than direct demonstration. To these three works, though in other respects very excellent, it is a considerable objection that the anatomical descriptions are much mixed with hypothetical speculation and reasonings on properties, and that the facts are by no means always distinguished from mere matters of opinion. At the same time J. G. Haase published an account of the lymphatics of the skin and intestines, and the plexiform nets of the pelvis.
To complete this sketch of the history of the anatomy of the lymphatic system, it may be added that Paolo Mascagni, who had been engaged from the year 1777 to 1781 in the same train of investigation, first demonstrated to his pupils several curious facts relating to the anatomy of the lymphatic system. When at Florence in 1782 he made several preparations, at the request of Peter Leopold, grand duke of Tuscany; and when the Royal Academy of Sciences at Paris announced the anatomy of this system for their prize essay appointed for March 1784, Mascagni resolved on communicating to the public the results of his researches--the first part of his commentary, with four engravings. Anxiety, however, to complete his preparations detained him at Florence till the close of 1785; and from these causes his work did not appear till 1787. These delays, however, unfavourable as they were to his claims of priority to Sheldon and Cruikshank, were on the whole advantageous to the perfection of his work, which is not only the most magnificent, but also the most complete that ever was published on the lymphatics. In his account of the vessels and their valves he confirms some of Hewson's observations and rectifies others. Their origin he proves by inference much in the same manner as Cruikshank; but he anticipates this author in the account of the glands, and he gives the most minute description of the superficial and deep lymphatics, both in the members and in the internal organs.
General accounts of the nerves had been given with various degrees of accuracy by Willis, Vieussens, Winslow, and the first Monro; and the subject had been much rectified and improved by the indefatigable Haller. The first example of minute descriptive neurography was given in 1748 by John Frederick Meckel, whose account of the fifth pair and of the nerves of the face will long remain a lasting proof of accuracy and research. The same subject was investigated in 1765 by Hirsch and in 1777 by Wrisberg. In 1766 Metzger examined the origin, distribution and termination of the first pair--a point which was afterwards very minutely treated by A. Scarpa, a professor of anatomy at Modena and Pavia, in his anatomical disquisitions, published in 1780; and the internal nerves of the nostrils were examined in 1791 by Haase. The optic nerve, which had been studied originally by Varoli, and afterwards by Mery, Duverney, J. F. Henkel, Moeller, Hein and Kaldschmid, was examined with extreme accuracy, with the other nerves of the organ of vision, by Zinn in his elaborate treatise. The phrenic nerves and the oesophageal branches of the vagus were studied by Haase; the phrenic, the abdominal and the pharyngeal nerves, by Wrisberg; those of the heart most minutely by Andersch; and the origins, formation and distribution of the intercostal nerves, by Iwanov, C. G. Ludwig, and Girardi. The labours of these anatomists, however, were eclipsed by the splendid works of Walter (1783) on the nerves of the chest and belly; and those of Scarpa (1794) on the distribution of the eighth pair and splanchnic nerves in general. In minuteness of description and in beauty of engraving these works have not yet been equalled, and will never perhaps be surpassed. About the same time, Scarpa, so distinguished in every branch of anatomical research, investigated the minute structure of the ganglions and plexuses. The anatomy of the brain itself was also studied (1780) with great attention by the second Monro, M. V. G. Malacarne and Vicq d'Azyr.
Lastly, the anatomy of the gravid uterus, which had been originally studied by Albinus, Roederer and Smellie, was again illustrated (1774) most completely by William Hunter, whose engravings will remain a lasting memorial of scientific zeal and artistic talent.
See also: History of anatomy