Galen’s theory of sanguification may be stated as follows: The chyle is received into the veins of the intestinal wall and carried thence to the liver, in which organ they are all gathered together into a single venous trunk which has received the name of “vena portae”—the vein of the gateway. Everything that is destined to enter the liver passes through this portal vein. In the organ itself the chyle undergoes certain modifications, the result of which is, first, to deprive it of its impurities and then, in addition, to effect other changes that convert it into blood. Aselli’s glory, then, consists in his having shown that chyle is taken up from the intestinal mucous membrane by a set of its own vessels, and not by the veins, as taught by Galen.
In 1651 Olaus Rudbeck of Arosen, Sweden, discovered the lymphatics of the intestinal canal and followed their distribution into the lymph nodes; he also established their relations with the thoracic duct and with the venous system.
Thus, thanks to the series of brilliant discoveries made by William Harvey, Realdus Columbus, Fabricius ab Acquapendente, Pecquet, Aselli and a few others, the doctrine of the circulation of the blood and of the part played by the accessory chyle and lymphatic vascular systems, became firmly established before the end of the seventeenth century.
CHAPTER XXX
ADVANCES MADE IN INTERNAL MEDICINE AND IN THE COLLATERAL BRANCHES OF BOTANY, PHARMACOLOGY, CHEMISTRY AND PATHOLOGICAL ANATOMY
General Remarks.—In the fundamental branches of medical knowledge—anatomy and physiology—advances of a very decided character were accomplished during the sixteenth and seventeenth centuries; and in the preceding chapters I have endeavored to give my readers some idea of the nature of these advances, of the men who were instrumental in effecting them, and of the extent to which the way was made easy, during this period, for the accomplishment of still further advances. In carrying on the work of correcting the many errors which were found to exist in the two departments mentioned, it was soon discovered that the obstacles to be overcome were of a serious character, and that the most formidable one of the group was what is universally known as Galenism. If I now refer to this subject once more, perhaps for the second or third time in the course of this history, it is because I fear that my remarks with regard to the harmful influence exerted by Galenism may not be rightly interpreted. For Galen’s personal character I entertain, as I have already stated in the section relating to Ancient and Mediaeval Medicine, the deepest respect, and I am filled with great admiration for what he accomplished in advancing the science of medicine; but at the same time I cannot overlook the fact that he was hemmed in by insurmountable limitations. No single human being, living at the beginning of the present era and surrounded, as Galen was, by a herd of jealous rivals, could have successfully bid defiance to those who considered it sacrilegious to dissect the dead body of a fellow man; and yet, without the knowledge which may only in this way be gained, how was it practicable for any individual, no matter how clever he might be, to lay the foundations for a further advance in medical knowledge? It seems to me therefore plain that Galen did all that lay in his power to advance the science of medicine; and whatever words of condemnation I may have employed in the text, when speaking of the Galenists, refer solely to those physicians of later centuries who were of such a narrow-minded type, so rigidly crystallized in the belief that Galen’s teachings had reached the limit of all possible knowledge in the science of medicine, that they did not hesitate to class the efforts of men like Vesalius as acts of unpardonable impiety. Galenism, then, refers to the very widely prevalent tendency among physicians of the fifteenth, sixteenth and seventeenth centuries to uphold the teachings of Galen as the only trustworthy code upon which they should depend for their guidance. In short, Galenism, at the period named, meant for medicine a complete arrest of development.
I have now arrived at a point in the history of medicine where, owing to the limited amount of space at my command, the difficulty of deciding as to what subjects and what individual workers in the field of medicine—a field now grown to very great proportions—shall receive consideration in my sketch. Having decided from the very outset that my best efforts shall be directed, consistently with a strict adherence to historical truth, toward making my account readable, I now find it absolutely necessary to jettison—if I may be permitted to use such a nautical expression—much really valuable cargo, and to put ashore, before continuing our voyage, many passengers of undoubted worth. Nobody need bemoan the loss of all these valuable treasures, for the great majority of them, I am confident, will be cared for properly by those authors who are privileged to treat this whole subject with some degree of thoroughness; and the reader, if he is familiar with German, will even now find, in the excellent general treatises of Haeser, von Gurlt, Pagel, Puschmann, Baas-Henderson and Neuburger, great stores of the most satisfactory information concerning the thousand and one details about which I am obliged to remain silent.
Internal Pathology.—During the fifteenth century the practitioners of medicine in Italy and France were still strongly under the influence of the teachings of the Arabian medical authors. One of the first writers in Italy to place the doctrines of internal medicine upon a firmer footing was Antonius Benevienus, a native of Florence (1440–1502). His treatise on some of the unusual causes of disease, which was printed in Florence in 1506, is said to be written in very clear language and to be based entirely upon cases which came under his own observation. According to Haeser the first improvements in the doctrines relating to pathological anatomy may be credited to Benevienus, who also taught that pathological phenomena should be studied by direct observation rather than from books.
Johannes Manardus of Ferrara (1462–1536) was a very sturdy opponent of astrology, and, in general, did all in his power to weaken the prevailing blind trust in the authority of the Arabian medical authors. But the two physicians who, next to Fabricius ab Acquapendente, stand out most conspicuously among their Italian contemporaries of the sixteenth and seventeenth centuries, are Fracastoro and Lancisi—the former a native of Northern and the latter of Southern Italy.
Hieronymus Fracastoro of Verona (1483–1553) ranks very high among the physicians of the first half of the sixteenth century for his valuable contributions to our knowledge of internal pathology. In the treatise which he published in 1546 on contagious maladies, he states in plain language his belief that the causes of diseases of this nature are to be found in living germs that are endowed with the power of propagating themselves. He divides these diseases into the following three groups:—
1, Those which infect only by contact; 2, Those which not only infect by contact, but at the same time leave behind a centre or focus of infection—in which category he places tuberculosis, elephantiasis, and similar diseases; and 3, Those which infect not only by direct contact, or through the agency of a residuary centre or focus of infection, but also those which are capable of spreading their infective elements over wide areas—for instance, the pestilential fevers, certain ophthalmias, variola, etc. (From Viktor Fossel’s version of Fracastoro’s treatise published in Leipzig in 1910.)