At the beginning of his residence in Alexandria, Erasistratus, like his great rival Herophilus, devoted his energies to anatomical and physiological researches. These two men evidently realized to the full how important it was to medicine, if it were to make a substantial advance beyond the point to which Hippocrates and his followers had already carried it, that a more complete understanding of the structure and working of the human body should be obtained; and their efforts in this direction were greatly aided by the enlightened views of the kings of Egypt, the Ptolemies, who did everything in their power to furnish these two investigators with all the human dissecting material they could use to advantage. They even went so far as to allow them the privilege of utilizing, for scientific purposes, the living bodies of imprisoned criminals, “in order that they might in this way learn the location, color, shape, size, construction, hardness, softness, smoothness, nature of external surface, protuberances and recesses of the individual organs during life.” The defense which they offered for permitting such vivisections was this: “It is permissible to sacrifice the lives of a few criminals if many worthy persons may thereby be permanently benefited in health, or have their lives prolonged.” (Puschmann.) Those who were opposed to such examinations upon human beings expressed their disapproval in the following terms: “This practice is not only cruel, but useless, and at the same time it derogates from the dignity of the healing art, which is intended to be a blessing and not a source of pain to man; for those in whom the abdominal cavity is first opened and then the diaphragm divided, die before it is possible to make the scientific examination ‘during life’ which constitutes, as it is claimed, the justification for the entire procedure.” (Puschmann.)
As regards the work done by Erasistratus in the departments of anatomy and physiology, the following statement may be made: He threw a great deal of additional light upon the structure of the lacteals, the valves of the heart, the brain, the nerves, and several other portions of the body; and he assigned to the pneuma, or breath,—of which he assumed that two kinds exist,—the most important rôle in the mechanism of life. According to the description given by Galen and reported by Le Clerc, the phenomena to which Erasistratus refers take place somewhat as follows: “When the thorax or chest expands, the lungs also undergo dilatation and fill themselves with air. This air, entering first by way of the trachea, ultimately reaches the anastomosing terminals of the bronchial tubes, from which locality the heart, by the act of dilatation, draws it into itself, and then, immediately afterward contracting, sends it, by way of the great artery (the Aorta), to every part of the body.” When it is considered that at this remote period of time nothing was known about oxygen and carbon dioxide, nor about the power of these elements to pass freely through a thin membrane (exosmosis and endosmosis), no surprise will be felt that Erasistratus carried the physiology of respiration no farther than he did. On the contrary, it is remarkable that he was able to describe so correctly this complicated process. In fact, none of his successors, up to the time when Harvey’s great discovery was announced, was able to furnish a better description. The physiology of gastric digestion was another of the problems concerning which Erasistratus held views that were different from those commonly accepted by the physicians of that time. The stomach, he maintained, first retracts when portions of food are introduced and then contracts in such a manner as to break them up into smaller and smaller fragments; this process taking the place of that of “coction,” as taught by Hippocrates. The resulting chyle passes from the stomach into the liver and is deposited in those spots where the finer branches of the vena cava and the terminal twigs of the channels which lead into the gall-bladder come together. Here the chyle breaks up into two portions, one of which—viz., that which contains biliary elements—gains an entrance into the channels that lead to the gall-bladder, while the other, which is composed of elements suitable for making pure blood, finds its way into the ramifications of the vena cava. While holding these views about the mode of transformation of gastric chyle into the bile and pure blood, Erasistratus did not hesitate to confess that he was unable to say whether bile was produced within the body or whether it already existed in the food that was taken into the stomach.
As regards the treatment of disease Erasistratus held certain views which were decidedly at variance with those maintained by the majority of his associates. Thus, for example, Straton, a distinguished disciple of this master, praises him for having banished bloodletting from the list of remedial measures, and adds that he can testify to the fact that Erasistratus had, by other means, cured all the diseases in which the ancients commonly employed bloodletting as the chief remedial agent. His favorite substitutes for the latter procedure were fasting, dieting, physical exercise, and—in cases of hemorrhage—placing ligatures around the arms and legs. Caelius Aurelianus is authority for the statement that, in certain very exceptional cases, Erasistratus did resort to bloodletting. Another of the latter’s tenets was his strong objection to the employment of purgatives and composite remedies. On the other hand, he appears to have attached considerable importance to the employment of chicory in the treatment of all disorders of the abdominal organs. One of the evidences of his preference for this drug is to be found in the care which he takes in describing how the plant should be prepared for remedial purposes. “Boil a bunch of the plant in water until the mass is thoroughly cooked; then cast it into a fresh supply of boiling water (to drive out still more of its bitter quality); and finally, upon removing it from the boiling water, place it for conservation in a receptacle containing oil. When it is required for use add a small quantity of weak vinegar.” Galen, in commenting jocosely upon the stress which Erasistratus lays upon these details, makes the remark: “As if our domestics did not know how to cook a bunch of chicory!”
Speaking of the effects produced by venom when one is bitten by a poisonous snake, Erasistratus remarks that “from the effects which the poison introduced in this manner produces, we may derive a general indication as to how a cure may be obtained. The poison, it will be noted, destroys very quickly the parts with which it comes in contact, and then, by spreading throughout the body, causes death. The thing to do, therefore, is to draw it as quickly as possible out of the body and thus arrest its further spread. To this end the wound should first be enlarged and its sides scarified; then, after it has been sucked, a cupping glass should be applied over it; and, finally, it should be cauterized.”
Erasistratus cultivated surgery as well as the other branches of medicine. He was a bold operator, as may be inferred from the fact that, in cases of scirrhus or other variety of tumor of the liver, he did not hesitate to incise the skin and overlying integuments, and then, after the peritoneal cavity had been opened, to apply directly to the seat of the disease such medicaments as seemed to him appropriate. On the other hand, he did not approve of paracentesis abdominis in cases of dropsical effusion, as a means of evacuating the fluid accumulated in the peritoneal cavity.
It appears that the disciples and successors of Herophilus and Erasistratus soon abandoned the exact methods which these two great masters had inaugurated and which, in a comparatively short time, had produced such admirable results, and then they fell back into the less arduous, the easy-going ways of speculation. Only a very few had sufficient strength of character to walk in the older pathway, and among the number were some who left Alexandria and established schools in the other cities—as, for example, Zeuxis, who organized a new centre of medical teaching at Laodicea, in the interior of Asia Minor, and Hikesios, who founded another school at Smyrna, on the seacoast of Lydia. It is not strange, therefore, that before many years had elapsed the two original schools at Alexandria died a natural death. As Pliny aptly writes, “It was so much more comfortable to sit on the benches of the schools and have learning poured into your ears than to wander daily through the desert outside in search of other nourishing plants.” As a further result of this deadness of the schools at Alexandria (that is, of the sect of the Dogmatics) the more serious-minded physicians espoused with eagerness the side of the Empirics—a sect which developed about this time, but which did not, it must be confessed, hold out much hope of solving the physiological and pathological problems of the day, but which nevertheless satisfied in some measure their needs as practitioners.
Philinus of Cos (286 B. C.) was looked upon as the founder of the school of the Empirics, and among its most distinguished disciples were: Serapion of Alexandria (279 B. C.), Glaucias, Apollonius Biblas, and—perhaps the most celebrated of them all—Herakleides of Tarentum (242 B. C.), who did such excellent work in the department of pharmacology. It was he, for example, who defined more precisely than had been done by any one of his predecessors the proper manner of employing opium. In addition, he wrote a commentary on the Hippocratic works and also separate treatises on medical, surgical and pharmaceutical topics. In the latter category belongs his book entitled “A Military Pharmacopoeia.” Last of all, Apollonius Mus, a distinguished follower of Herophilus, deserves to be mentioned because it was he who perfected the preparation of castor oil. At a still later date (158 B. C.) Zopyrus proved himself to be a most worthy successor to Herakleides. It was he who first classified drugs according to the effects which they produce, and he also invented or discovered the preparation named “ambrosia,” a general antidote for poisons of all kinds. Kings and princes were, at that period, in constant fear of being poisoned, and so it came about that those who were skilled in the knowledge and preparation of drugs were greatly stimulated by their royal patrons to find efficient antidotes. It is narrated that Attalus Philometer, King of Pergamum, the native city of the famous physician Galen, and Mithridates Eupator, King of Pontus, cultivated poisonous plants in their gardens and tried the effects of the poisons distilled from them on criminals. They also encouraged in every possible way the preparation of antidotes; and thus was compounded a mixture which even to-day is still known by the name of “Mithridaticum.” For centuries it was a very popular remedy for poisoning by snake-bite. Le Clerc states that one of the first things that the great Roman general Pompey did, after conquering Mithridates and gaining possession of his palace (about 64 B. C.), was to have a careful search made for the recipe of this famous antidote. Upon finding it he was surprised to learn what simple ingredients it was composed of—viz., “20 leaves of rue, a pinch of salt, two nuts, and two dried figs.” The theriacum, which one hundred years later was modeled after the Mithridaticum, contained a great deal of honey and a large number of unimportant drugs, introduced—as Pliny claims—“to magnify the importance of the apothecary’s art, rather than to increase the curative effects of the remedy.”
The scepticism which already at that period had begun to take possession of many of the best minds manifested itself in the form of a disbelief in the possibility of discovering full scientific truth, and men therefore taught the doctrine that the human understanding is not capable of attaining anything higher than probability. The acceptance of such a doctrine naturally acted as a powerful hindrance to all further original research. And so the Empirics neglected the study of anatomy and physiology as something quite superfluous and unprofitable. They gave no further thought to the causes of disease, and were quite satisfied simply to observe its manifestations, to investigate the factors which appeared to bring it into a state of activity, and to search for the means of effecting a cure. In carrying on work of this character, they of course derived help, not only from their own experience, but also from that of others—which latter became in time a matter of history. When they encountered new experiences and were unable to supply a satisfactory explanation they resorted to a third method—that of reasoning by analogy. Upon this triple support—one’s own individual experience, the experience of others stored up in the form of history, and reasoning by analogy—rested the entire structure of empiricism.
Strange as it may at first appear, the science of medicine from this time onward made no further conspicuous progress until the middle of the seventeenth century of the present era. In certain branches of practical medicine—as, for example, pharmacology, obstetrics and general surgery, and also in certain special departments—the Empirics made a number of material additions to our knowledge; but in all essential particulars the medical science taught throughout this period of about two thousand years varied but little from that taught at Alexandria one hundred or two hundred years before the birth of Christ. This extraordinary phenomenon of almost complete arrest of development for so long a period of time should not excite surprise, for something of a similar nature has certainly occurred in other departments of human knowledge.
The further history of the medical sects which flourished under the Ptolemies and for a short time afterward, when Alexandria became a colony of the Roman Empire, need not detain us long. Daremberg furnishes a chronological chart of the physicians who played a more or less prominent part in the work of these sects, and from this it appears that they numbered thirty-four in all—ten followers of Herophilus, fourteen of Erasistratus, and ten Empirics. Callamachur and Bacchius, who belonged to the first of these groups, deserve to be mentioned because they were its most distinguished members and because they were the first physicians who wrote commentaries on the writings of Hippocrates. In the sect of the Empirics the next in importance after Philinus of Cos is Serapion of Alexandria. Mantias, another disciple of Herophilus, gained considerable reputation from the fact that he was the first to collect together into a single treatise the different pharmaceutical formulae that were then in general use. He was also an authoritative writer on surgical topics.