The authority of Galen, at once a despotism and a religion, was scarcely ever called in question until the sixteenth century. No attempt worth recording was made during thirteen hundred years to extend the boundary of scientific knowledge in anatomy and physiology. It is true that the scholastic philosopher, Albertus Magnus, who was for a short time (1260-1262) Bishop of Ratisbon, in the middle of the thirteenth century wrote a "History of Animals," which was a remarkable production for the age in which he lived; although Sir Thomas Browne, in his famous "Enquiries into Common Errors," speaks of these "Tractates" as requiring to be received with caution, adding as regards Albertus that "he was a man who much advanced these opinions by the authoritie of his name, and delivered most conceits, with strickt enquirie into few."
As regards human anatomy, it was considered, during the Middle Ages, to be impiety to touch with a scalpel "the dead image of God," as man's body was called. Mundinus, the professor of medicine at Bologna from 1315 to 1318, was the first to attempt any such thing. He exhibited the public dissection of three bodies, but by this created so great a scandal that he gave up the practice, and contented himself with publishing a work, "De Anatome," which formed a sort of commentary on Galen. This work, with additions, continued to be the text-book of the schools until the time of Vesalius, who founded the study of anatomy as nowadays pursued.
Andreas Vesalius was born at Brussels, on the last day of the year 1514, of a family which for several generations had been eminent for medical attainments. He was sent as a boy to Louvain, where he spent the greater part of his leisure in researches into the mechanism of the lower animals. He was a born dissector, who, after careful examination, in his early days, of rats, moles, dogs, cats, monkeys, and the like, came, in after-life, to be dissatisfied with any less knowledge of the anatomy of man.
He acquired great proficiency in the scholarship of the day. Indeed the Latin, in which he afterwards wrote his great work, is so singularly pure that one of his detractors pretended that Vesalius must have got some good scholar to write the Latin for him. Latin was not the only language in which he was proficient; he added Greek and Arabic to his other accomplishments, and this for the purpose of reading the great biological works in the languages in which they were originally written. From Louvain the youth went to Paris, where he studied anatomy under a most distinguished physician, Sylvius. It was the practice of that illustrious professor to read to his class Galen on the "Use of Parts," omitting nearly all the sections where exact knowledge of anatomical detail was necessary. Sometimes an attempt was made to illustrate the lecture by the dissection of a dog, but such illustration more often exposed the professor's ignorance than it added to the student's knowledge. Indirectly, however, it did good, for whenever Sylvius, after having tried in vain to demonstrate some muscle, or nerve, or vein, left the room, his pupil Vesalius slipped down to the table, dissected out the part with great neatness, and triumphantly called the professor's attention to it on his return.
Besides studying under Sylvius, Vesalius had for his teacher at Paris the famous Winter, of Andernach, who was physician to Francis I. This learned man, in a work published three years after this period, speaks of Vesalius as a youth of great promise. At the age of nineteen Vesalius returned to Louvain; and here for the first time he openly demonstrated from the human subject. In this connection a somewhat ghastly story is told, which serves to show the intensity of the enthusiasm with which our anatomist was inspired. On a certain evening it chanced that Vesalius, in company with a friend, had rambled out of the gates of Louvain to a spot where the bodies of executed criminals were wont to be exposed. A noted robber had been executed. His body had been chained to a stake and slowly roasted; and the birds had so entirely stripped the bones of every vestige of flesh, that a perfect skeleton, complete and clean, was suspended before the eyes of the anatomist, who had been striving hitherto to piece together such a thing out of the bones of many people, gathered as occasion offered. Mounting upon the shoulder of his friend, Vesalius ascended the charred stake and forcibly tore away the limbs, leaving only the trunk, which was securely bound by iron chains. With these stolen bones under their clothes the two youths returned to Louvain. In the night, however, and alone, the sturdy Vesalius found his way again to the place—which to most men, at any rate in those times, would have been associated with unspeakable horrors—and there, by sheer force, wrenched away the trunk, and buried it. Then leisurely and carefully, day after day, he smuggled through the city gates bone after bone. Afterwards, when he had set up the perfect skeleton in his own house, he did not hesitate to demonstrate from it. But such an act of daring plunder could not escape detection, and he was banished from Louvain for the offence. This story is here quoted only to show the extraordinary physical and moral courage which the anatomist possessed; which upheld him through toils, dangers, and disgusts; and by which he was strengthened to carry on, even in a cruel and superstitious age, and placed, as he was, on the very threshold of the Inquisition, a work at all times repulsive to flesh and blood.
After serving for a short time as a surgeon in the army of the Emperor Charles V., Vesalius went to Italy, where he at once attracted the attention of the most learned men, and became, at the age of twenty-two, Professor of Anatomy at the University of Padua. This was the first purely anatomical professorship that had been established out of the funds of any university. For seven years he held the office, and he was at the same time professor at Bologna and at Pisa. During these years his lectures were always well attended, for they were a striking innovation on the tameness of conventional routine. In each university the services of the professor were confined to a short course of demonstrations, so that his duties were complete when he had spent, during the winter, a few weeks at each of the three towns in succession. He then returned to Venice, which he appears to have made his head-quarters. At this city, as well as at Pisa, special facilities were offered to the professor for obtaining bodies either of condemned criminals or others. At Padua and Bologna the enthusiasm of the students, who became resurrectionists on their teacher's behalf, kept the lecture-table supplied with specimens. They were in the habit of watching all the symptoms in men dying of a fatal malady, and noting where, after death, such men were buried. The seclusion of the graveyard was then invaded, and the corpse secretly conveyed by Andreas to his chamber, and concealed sometimes in his own bed. A diligent search was at once made to determine accurately the cause of death. This pitiless zeal for correct details in anatomy, associated as it was with indefatigable practice in physic, appeared to Vesalius, as it does to his successors of to-day, to be the only satisfactory method of acquiring that knowledge which is essential to a doctor. Thus it was that he, who at the age of twenty-two was able to name, with his eyes blindfolded, any human bone put into his hand, who was deeply versed in comparative anatomy, and had more accurate knowledge of the human frame than any graybeard of the time, enjoyed afterwards a reputation as a physician which was unbounded. One illustration of his sagacity in diagnosis will suffice. A patient of two famous court physicians at Madrid had a big and wonderful tumour on the loins. It would have been easily recognized in these days as an aneurismal tumour, but it greatly puzzled the two doctors. Vesalius was therefore consulted, and said, "There is a blood-vessel dilated; that tumour is full of blood." They were surprised at such a strange opinion; but the man died, the tumour was opened; blood was actually found in it, and we are told in admirationem rapti fuère omnes.
It was not until after Vesalius had been three years professor that he began to distrust the infallibility of Galen's anatomical teaching. Constant practical experience in dissection, both human and comparative, slowly convinced him that—great anatomist as the "divus homo" had undoubtedly been—his statements were not only incomplete, but often wrong; further, that Galen very rarely wrote from actual inspection of the human subject, but based his teaching on a belief that the structure of a monkey was exactly similar to that of a man. With this conviction established, Vesalius proceeded to note with great care all the discrepancies between the text of Galen and the actual parts which it endeavoured to describe, and in this way a volume of considerable thickness was soon formed, consisting entirely of annotations upon Galen. The generally received authorities being thus found to be unreliable, it became necessary in the next place to collect and arrange the fundamental facts of anatomy upon a new and sounder basis. To this task Vesalius, at the age of twenty-five, devoted himself, and began his famous work on the "Fabric of the Human Body." Owing possibly to the good fortune of his family, and to the income which he derived from his professorships, Andreas was able to secure for his work the aid of some of the best artists of the day. To Jean Calcar, one of the ablest of the pupils of Titian, are due the splendid anatomical plates which illustrate the "Corporis Humani Fabrica," and which are incomparably better than those of any work which preceded it. To him most likely is due also the woodcut which adorns the first page, and which represents the young Vesalius, wearing professor's robes, standing at a lecture-table and pointing out, from a robust subject that lies before him, the inner secrets of the human body; while the tiers of benches that surround the professor are completely crowded with grave doctors struggling to see, even climbing upon the railings to do so.
But throughout the work the plates are used simply to illustrate and elucidate the text, and the information furnished in the latter is minute and accurate, and stated in well-polished Latin. As the author proceeds, he finds it necessary to disagree with Galen, and the reasons for this disagreement are given. The inevitable result follows that Vesalius is placed at issue not only with "the divine man," but also with all those who for thirteen centuries had unquestioningly followed him. Such a result Vesalius must have foreseen. It was not, therefore, a great surprise to him, perhaps, to receive, soon after the publication of his work, a violent onslaught from his old master Sylvius. He simply replied to it by a letter full of respect and friendly feeling, inquiring wherein he had been guilty of error. The answer he got was that he must show proper respect for Galen, if he wished to be regarded as a friend of Sylvius.
In 1546, three years after the publication of his great work, Andreas was summoned to Ratisbon to exercise his skill upon the emperor, and from that date he was ranked among the court physicians. In the same year, 1546, in a long letter, entitled "De usu Radicis Chinæ," he not only treats of the medicine by which the emperor's health had been restored, but he vindicates his teaching against his assailants, and again gives cumulative proof of the fact that Galen had dissected only brutes.
It was the practice of Vesalius, while he was professor in Italy, to issue a public notice the day before each demonstration, stating the time at which it would take place, and inviting all who decried his errors to attend and make their own dissections from his subject, and confound him openly. It does not appear that any one was rash enough ever to accept the challenge; yet, although the majority of the young men were on the side of Vesalius, the older teachers continued to regard him as a heretic, and in 1551 Sylvius published a bitterly personal attack. It was nothing to him that the results of actual dissection were against him—he even went so far as to assert that the men of his time were constructed somewhat differently to those of the time of Galen! Thus, to the proof that Vesalius gave that the carpal bones were not absolutely without marrow, as Galen had asserted, Sylvius replied that the bones were harder and more solid among the ancients, and were, in consequence, destitute of medullary substance. Again, when Vesalius showed that Galen was wrong in describing the human femur and humerus as greatly curved, Sylvius explained the discrepancy by saying that the wearing of narrow garments by the moderns had straightened the limbs.
Through these attacks, however, the writings of Vesalius fell into somewhat bad odour in the court; for in that very superstitious age there was a kind of vague dread felt of reading the works of a man against whom such serious charges of arrogance and impiety were brought. And so it came about that when he received the summons to take up his residence permanently at Madrid, and the orthodoxy of the day seemed for the moment to triumph, in a fit of proud indignation, he burned all his manuscripts; destroying a huge volume of annotations upon Galen; a whole book of medical formulæ; many original notes on drugs; the copy of Galen from which he lectured, and which was covered with marginal notes of new observations that had occurred to him while demonstrating; and the paraphrases of the books of Rhases, in which the knowledge of the Arabian was collated with that of the Greeks and others. The produce of the labour of many years was thus reduced to ashes in a short fit of passion, and from this time Vesalius lived no more for controversy or study. He gave himself up to pleasure and the pursuit of wealth, resting on his reputation and degenerating into a mere courtier. As a practitioner he was held in high esteem. When the life of Don Carlos, Philip's son, was despaired of, it was Vesalius who was called in, and who, seeing that the surgeons had bound up the wound in the head so tightly that an abscess had formed, promptly brought relief to the patient by cutting into the pericranium. The cure of the prince, however, was attributed by the court to the intercession of St. Diego, and it is possible that on the subject of this alleged miraculous recovery Vesalius may have expressed his opinion rather more strongly than it was safe for a Netherlander to do. At any rate, the priests always looked upon him with dislike and suspicion, and at length they and the other enemies of the great anatomist had their revenge.
A young Spanish nobleman had died, and Vesalius, who had attended him, obtained permission to ascertain, if possible, by a post-mortem examination, the cause of death. On opening the body, the heart was said—by the bystanders—to beat; and a charge, not merely of murder, but of impiety also, was brought against Vesalius. It was hoped by his persecutors that the latter charge would be brought before the Inquisition, and result in more rigorous punishment than any that would be inflicted by the judges of the common law. The King of Spain, however, interfered and saved him, on condition that he should make a pilgrimage to the Holy Land. Accordingly he set out from Madrid for Venice, and thence to Cyprus, from which place he went on to Jerusalem, and was returning, not to Madrid, but to Padua, where the professorship of physic had been offered him, when he suffered shipwreck on the island of Zante, and there perished miserably of hunger and grief, on October 15, 1564, before he had reached the age of fifty. His body was found by a travelling goldsmith, who recognized, notwithstanding their starved outlines, the features of the renowned anatomist, and respectfully buried his remains and raised a statue to his memory.
Two of the works of this great man have been already referred to, namely: "De Corporis Humani Fabrica;" "De usu Radicis Chinæ." Besides these the following have appeared: "Examen Observationum Gabrielis Fallopii;" "Gabrielis Cunei Examen, Apologiæ Francisci Putei pro Galeno in Anatome;" a great work on Surgery in seven books.
With respect to the last of these, it may be sufficient to remark that there is every reason to believe that the name of the famous anatomist was stolen after his death to give value to the production, which was compiled and published by a Venetian named Bogarucci; and that Vesalius is not responsible for the contents.
The other works are undoubtedly genuine. In 1562 Andreas seems to have been roused for a short time from the lethargy into which he had sunk, by an attack from Franciscus Puteus; for to this attack a reply appeared—from a writer calling himself Gabriel Cuneus—which has always been attributed by the most competent authorities to Vesalius himself. In this rather long work, covering as it does more than fifty pages in the folio edition, the views of Vesalius, which are at variance with Galen, are gone through seriatim and defended.
In 1561 Fallopius, who had studied under Vesalius, published his "Anatomical Observations," containing several points in which he had extended the knowledge of anatomy beyond the limits reached by his master. He had taught publicly for thirteen years at Ferrara, and had presided for eight years over an anatomical school, so that he was no novice in the field of biology. Yet so completely had Vesalius lost the philosophic temperament that he regarded this publication as an infringement of his rights, and in this spirit wrote an "Examen Observationum Fallopii," in which he decried the friend who had made improvements on himself, as he had been decried for his improvements on Galen. The manuscript of this work, finished at the end of December, 1561, was committed by the author to the care of Paulus Teupulus of Venice, orator to the King of Spain, who was to give it to Fallopius. The orator, however, did not reach Padua until after the death of Fallopius, and he consequently retained the document until Vesalius, on his way to Jerusalem, took possession of it, and caused it to be published without delay. It appeared at Venice in 1564.
The letter on the China root—a plant we know nowadays as sarsaparilla—by the use of which the emperor's recovery was effected, has been already referred to. It was addressed to the anatomist's friend, Joachim Roelants. Very little space, however, is taken up with a description of the medicine which gives title to the letter. Something certainly is said of the history and nature of the plant, the preparation of the decoction and its effects; but the writer soon introduces the subject which was at that time of very vital importance to him, namely, his position with regard to the statements of Galen and his followers. He collects together various assertions of the Greek anatomist, on the bones, the muscles and ligaments, the relations of veins and arteries, the nerves, the character of the peritoneum, the organs of the thorax, the skull and its contents, etc., and shows from each and all of these that reference had not been made to the human subject, and that therefore the statements were unreliable.
To the work on the "Fabric of the Human Body" we have already alluded, as well as to the causes which led to its being written. More than half of this great treatise is occupied with a minute description of the build of the human body—its bones, cartilages, ligaments, and muscles. It may have been owing to the thorough acquaintance which Vesalius showed with these parts that his detractors pretended afterwards that he only understood superficial injuries. But other branches of anatomy are fully dealt with. The veins and arteries are described in the third book, and the nerves in the fourth; the organs of nutrition and reproduction are treated of in the next; while the remaining two books are devoted to descriptions of the heart and brain.
Vesalius gives a good account of the sphenoid bone, with its large and small wings and its pterygoid processes; and he accurately describes the vestibule in the interior of the temporal bone. He shows the sternum to consist, in the adult, of three parts and the sacrum of five or six. He discovered the valve which guards the foramen ovale in the fœtus; and he not only verified the observation of Etienne as to the valve-like fold guarding the entrance of each hepatic vein into the inferior vena cava, but he also fully described the vena azygos. He observed, too, the canal which passes in the fœtus between the umbilical vein and vena cava, and which has since been known as the ductus venosus. He was the first to study and describe the mediastinum, correcting the error of the ancients, who believed that this duplicature of the pleura contained a portion of the lungs. He described the omentum and its connections with the stomach, the spleen, and the colon; and he enunciated the first correct views of the structure of the pylorus, noticing at the same time the small size of the cæcal appendix in man. His account of the anatomy of the brain is fuller than that of any of his predecessors, but he does not appear to have well understood the inferior recesses, and his description of the nerves is confused by regarding the optic as the first pair, the third as the fifth, and the fifth as the seventh. The ancients believed the optic nerve to be hollow for the conveyance of the visual spirit, but Vesalius showed that no such tube existed. He observed the elevation and depression of the brain during respiration, but being ignorant of the circulation of the blood, he wrongly explained the phenomenon.
Exclusively an anatomist, he makes but brief references in his great work to the functions of the organs which he describes. Where he differs from Galen on these matters he does so apologetically. He follows him in regarding the heart as the seat of the emotions and passions—the hottest of all the viscera and source of heat of the whole body; although he does not, as Aristotle did, look upon the heart as giving rise to the nerves. He considers the heart to be in ceaseless motion, alternately dilating and contracting, but the diastole is in his opinion the influential act of the organ. He knows that eminences or projections are present in the veins, and indeed speaks of them as being analogous to the valves of the heart, but he denies to them the office of valves. To him the motion of the blood was of a to-and-fro kind, and valves in the veins acting as such would have interfered with anything of the sort. He expresses clearly the idea, that was entertained in the old physiology, of the attractions exerted by the various parts of the body for the blood; and especially that of the veins and heart for the blood itself. "The right sinus of the heart," he says, "attracts blood from the vena cava, and the left attracts air from the lungs through the arteria venalis (pulmonary vein), the blood itself being attracted by the veins in general, the vital spirit by the arteries." Again, he speaks of the blood filtering through the septum between the ventricles as if through a sieve, although he knows perfectly well from his dissection that the septum is quite impervious.
It will thus be seen that the physiological teaching of Galen was left undisturbed by Vesalius.
 See Professor Morley's article on "Anatomy in Long Clothes," in Fraser's Magazine, 1853, from which most of the facts in this sketch have been taken.