The century of Columbus

by James J. Walsh

Another of the distinguished anatomists of the time was Aranzius, who was the Professor of Anatomy in the Papal University of Bologna for some thirty-two years just after the close of our period, having received his training, however, in our century. He gave the first correct account of the anatomy of the foetus and was the first to show that the muscles of the eye do not arise from the dura mater but from the margin of the optic cavity. He confirmed Columbus' views with regard to the course of the blood in passing from the left to the right side of the heart, and made a number of discoveries in the anatomy of the brain. To him we owe the term hippocampus, and he described the fourth ventricle very accurately, calling it the cistern of the cerebellum.

The scientific development of physiology followed immediately, as might be expected, on that of anatomy. Indeed, Vesalius deserves almost as much credit for what he did for physiology as for his researches in anatomy. The functions of bones, muscles and organs were, as we have said, carefully discussed in connection with the descriptions of their form, location and relations to other organs.

Probably the best way to present the advance made in physiology at this time is to review the important steps of progress toward that greatest generalization in modern physiology, the circulation of the blood. Much more had been known of it before this time than is usually thought, and probably even the ancients, especially in Greece, had more than a hint of it. Before Columbus' Century closed, the discovery of the pulmonary circulation was an accomplished fact, and there was more than an inkling of the existence of the general circulation. The full description of this was not made until afterwards, but it was not long delayed, and it came from a man who belongs to our time. It did not receive that thorough scientific statement which was to make it a fundamental principle in the biological science of the time until Harvey's day, nor indeed for some [{369}] time after Harvey's thoroughly scientific description and demonstration. [Footnote 32]

[Footnote 32: How clearly Rabelais understood the function of the circulation, though he did not properly appreciate its physiological anatomy, may be readily seen from his famous passage on the circulation, in which he talks about the blood as "the rivulet of gold which is received with such joy by all the organs because it is their sole restorative." A portion of the passage is worth while quoting because it represents a popularization of the scientific knowledge of the time. Rabelais was writing not for physicians nor even medical students, but for the educated general public of the time. He said:

"The Spleen draweth from the Blood its terrestrial parts, viz., the Grounds, Lees or thick Substance settled in the bottom thereof, which you term Melancholy; the Bottle of the Gall subtracts from thence all the superfluous Choler: whence it is brought to another Shop or Workhouse to be yet better purified and refined, that is the Heart, which by its agitation of Diastolick and Systolick Motions so neatly subtiliseth and inflames it, that in the right-side Ventricle it is brought to Perfection and through the Veins is sent to all the Members; each Parcel of the Body draws it then into itself, and after it's own fashion, is cherished and alimented by it: Feet, Hands, Thighs, Arms, Eyes, Ears, Back, Breast, yea, all; and thus it is that who before were Lenders, now become Debtors, The Heart doth in its left-side Ventricle so thinnify the Blood that it thereby obtains the name of Spiritual; which being sent through the Arteries to all the members of the Body, serveth to warm and winnow or fan the other Blood which runneth through the Veins; The Lights never cease with its Lappets and Bellows to cool and refresh it; in Acknowledgment of which good the Heart through the Arterial Vein imparts unto it the choicest of it's Blood: At last it is made so fine and subtle within the Rete Mirabile, that thereafter those Animal Spirits are framed and composed of it; by means whereof the Imagination, Discourse, Judgment, Resolution, Deliberation, Ratiocination, and Memory have their Rise, Actings and Operations.">[

Harvey himself indeed has acknowledged his indebtedness to these men of preceding generations, and any fair-minded review of the subject makes it clear that there was a gradual progress towards this all-important generalization for several generations, and not that sudden discovery which is sometimes thought to have taken place. In 1546 Servetus, who had been Professor of Anatomy at Paris, but who had a tendency to dabble in theology that subsequently proved unfortunate for him, for, as will be recalled, he was burnt to death by Calvin [{370}] at Geneva in 1553, sent to Curio, who was teaching anatomy at Padua, a manuscript copy of his "Restitutio Christianismi," "The Restoration of Christendom," in which he described completely the circulation of the blood in the lungs.

Because Servetus' description first appeared in a theological work, it has sometimes seemed to commentators that his expressions were scarcely more than accidental and that it was only by chance that he reached such a generalization. To say this, however, is to ignore Servetus' career. He was an investigator of a thoroughly scientific spirit, living in a time when discoveries, particularly in the biological sciences, were being made all round him, and he had made many dissections, had taught anatomy at the University of Paris and was exactly in the most appropriate position to make such a new discovery. He had done some distinguished work in botany, he had suggested some modifications in pharmacology which met with violent opposition, but have since been approved, and like so many of the men of the Renaissance he had "taken all knowledge for his province" with a wonderful degree of success. Unfortunately he invaded theology and then got into trouble. He had to fly from Paris, though probably the prosecution of him was due not a little to the enemies created by his uncompromising spirit in the controversy over the use of syrups. He was protected by the Archbishop of Vienne, who had him as physician for a dozen of years, and it was Calvin who denounced him to the Roman authorities in such a way that even the friendly Archbishop could no longer protect him. He was allowed to escape from jail by connivance, went to Geneva and there met his sad fate.

It may not be true, as has been said, that by putting him to death Calvin put back the development of physiology for three-quarters of a century until Harvey's time, but undoubtedly Servetus' death was a very unfortunate incident for science.

Just about this same time a series of discoveries in Italy led up to the thought of the existence of a circulation of the blood in lungs and body. Already in the first edition of his great text-book of anatomy in 1543, Vesalius had expressed doubts [{371}] with regard to the Galenic doctrine that the blood passed through the septum of the heart from one ventricle to another, and these doubts he emphasized in the second edition. In 1547 Cananus, Professor of Anatomy at Ferrara, observed the valves in the veins, and these are said to have been described even before this, though the doctrine of their existence and function was not generally accepted in science until after the more complete description made by Fabricius of Aquapendente, who was born in our century but did his important work afterwards. Columbus, who was teaching anatomy at the Papal University of the Sapienza in Rome, was even more complete and explicit in his description of the pulmonary circulation than had been Servetus. The question as to whether he knew of Servetus' discovery has never been absolutely settled, though there seems very little likelihood of it. Apparently the one possibility is that a copy of the edition of the "Restitutio Christianismi" which was burned with its unfortunate author, may have been spared and found its way to Rome. Rome is indeed the least likely place for such a book to have wandered, and only two copies of that first edition are definitely known to have escaped. Of these Columbus could have known nothing. Harvey himself, to quote Professor Foster in his "History of Physiology," spoke of Columbus with respect as of a great authority.

Columbus' work has sometimes been minimized in Western Europe, especially by the English, apparently in the fear lest recognition for him should lessen Harvey's glory. Harvey himself, however, quotes Columbus as an authority in his work on the circulation, and the Italian anatomist, who had been Vesalius' assistant, was undoubtedly a great teacher, investigator, dissector, experimenter, observer and writer with regard to a number of phases of medical science. He was the first to insist on demonstrations of living animals as valuable in the teaching of medicine. He declared that one could learn more about the functions of the body from the dissection of a single dog than from feeling the pulse for hours and merely studying Galen. He made demonstrations on living animals and was constantly engaged in trying to find out function as well as anatomical details. A number of workers in the medical [{372}] sciences toward the end of Columbus' Century were making experiments of various kinds on living and dead animals in order to develop physiology. Eustachius studied the kidneys experimentally, and the sensory functions were investigated very carefully and with the true scientific spirit.