One disease after another was investigated. It was demonstrated in the case of both the lower animals and men that a large number of maladies and plagues might be completely disarmed of their terrors by the process of inoculation. The name of Pasteur became more and more famous. The celebrated Pasteur Inst.i.tute was founded at Paris, under the patronage of the French Government, and in some sense under the patronage of the whole world. To this establishment diseased subjects were taken for treatment, and here experimentation was carried on over a wide range of facts.

The value of the results attained can hardly be overestimated. The fear which mankind have long entertained on account of plagues and epidemics, and the loss which the animal industries of the world have sustained, were largely abated. As yet the use of the Pasteur methods for the prevention and cure of disease is by no means universal; but the knowledge which has come of his investigations and of the results of them has diffused itself among all civilized nations, and the hygienic condition of almost every community has been most favorably affected by the new knowledge which we possess of bacteria and of the means of destroying them.

Pasteur, whose recent death has been mourned by the best part of mankind, was an explorer and forerunner. His industry in his chosen field of investigation was prodigious. When he was already nearly seventy years of age, he undertook the investigation of hydrophobia, with the purpose of discovering, if he might, the germ of that dreaded disease, thus preparing a method for inoculation against it.

Hydrophobia is one of the most subtle diseases ever known. So obscure and uncertain are its phenomena that many able men have been led to doubt the _existence_ of such a disease! The mythological origin of the malady in the supposed influence of a dog-star seemed to strengthen the view that hydrophobia, as a specific disease, does not exist. It is undeniably true that the great majority of the cases of so-called rabies are pure myths. Under investigation they melt away into nothing but alarm and fiction. However, there appeared to be a residue of actual hydrophobia, though the disease as tested by its name exists in fancy rather than fact.

In any event, Pasteur began to investigate hydrophobia, and at length discovered the bacilli which produce it. At least he found in animals affected with rabies, notably in the spinal marrow of such animals, minute living organisms, having the form of thread-like animalculae, with heads at one end. The microscope showed also among these thread-like bodies other organisms that were like small circular black specks, or disks.

The next step in the work was to test the result by inoculating a well animal with these bodies. Pasteur selected rabbits for his experimentation. When the experiment was made, the inoculated rabbit was presently attacked with the disease, and soon died in spasms. The repet.i.tion of the experiment was attended with like results.

The philosopher next tried his established method of domesticating, or attenuating, the poison. The spinal cord of a rabid dog was obtained, and with this the first rabbit was inoculated. In about two weeks it took hydrophobia. Hereupon the spinal cord was extracted, and the second rabbit was inoculated; then the third; then the fourth, and so on. It was observed, however, that at each stage the intensity of the disease was in this way strangely increased; but the period of inoculation became shorter and shorter.

It was next found that by preserving the spinal cords of the animals that had died of the disease--by preserving them in dry tubes--the poison gradually lost its power. At last the virus seemed to die altogether. Then the experiment of inoculating against the disease was begun. A dog was first inoculated with dead virus. No result followed.

Then he was inoculated with stale virus, and then with other virus not so stale. It was found that by continuing this process the animal might be rendered wholly insusceptible to the disease.

The next step was the human stage of experimentation. It was in July of 1885 that Pasteur first employed his method on a human subject. A boy had been bitten and lacerated by a rabid dog. The inoculation was thought to prove successful. Soon afterward some bitten children were taken from the United States to Paris, and were treated against the expected appearance of hydrophobia. Others came from different parts of the continent. Within fourteen months more than two thousand five hundred subjects were treated, and it is claimed that the mortality from hydrophobia was reduced to a small per cent of what it had been before.

It should be said, however, that neither have the results arrived at by Pasteur respecting the character of rabies been so clear, nor have his experiments on subjects supposed to be poisoned with the disease been so successful as in the case of other maladies. It remains, nevertheless, to award to Louis Pasteur _the first rank_ among the bacteriologists of our day, as well as a first place among the philanthropists of the century. Only Robert Koch, of Germany, is to be cla.s.sed in the same list with him.

KOCH'S BATTLE WITH THE INVISIBLE ENEMY.

There was a great _negative_ reason for the success of the World's Columbian Exposition. The cholera did NOT come! It is quite true that there is no _if_ in history; but IF the cholera had come, IF the plague had broken out in our imperial Chicago, what would have become of the Columbian Exposition? Certainly the Man of Genoa would have had to seek elsewhere for a great international gathering in his honor.

The cholera did not arrive, although it was expected. The antecedent conditions of its coming were all present; but it came not. The American millions discerned that the dreaded plague was at bay; a feeling of security and confidence prevailed; the summer of 1893 went by, and not a single case of Asiatic cholera appeared west of the Alleghenies. We are not sure that a single case appeared on the mainland of North America. And why not?

It was because the increasing knowledge of mankind, reinforced with philanthropy and courage, had drawn a line north and south across Western Europe, and had said, _Thus far and no farther_. Indeed, there were several lines drawn. The movement of cholera westward from the Orient began to be obstructed even before it reached Germany. It was obstructed in Italy. It was obstructed seriously on the meridian of the Rhine. It was obstructed almost finally at the meridian of London.

It was completely and gloriously obstructed at the harbor of New York.

Civilization has never appeared to a better advantage than in the building of her defences against the westward invasion of cholera.

There have been times within two decades of the present when in the countries east of the Red Sea 3000 people have died daily of the Asiatic plague. Egypt has been ravaged. The ports of the Mediterranean have been successfully invaded. Commerce, reckless of everything except her own interests, has taken the infection on shipboard, and sailed with it to foreign lands, as though it were a precious cargo!

Importers, anxious for merchandise, have stood ready to receive the plague, and plant it without regard to consequences. But in the midst of all this, a new power has arisen in the world, and standing with face to the east, has drawn a sword, before the circle of which even the spectral shadow of cholera has quailed and gone back! Humanity might well break out in rhapsody and jubilee over this great victory.

Among the personal agencies by which cholera has been excluded from Europe and America, first and greatest is Dr. Robert Koch, of Berlin.

He, more than any other one man, has contributed to the glorious exemption. Dr. Koch, now by the favor of his Emperor, Baron Koch, is one of those heroic spirits who go before the human race exploring the route, casting up a highway and gathering out the stones. Thus shall the feet of the oncoming millions be not bruised and their shouts of joy be not turned to lamentation.

Robert Koch was born at Klausthal, in the Hartz mountains, on the eleventh of December, 1843. He is a German of the Germans. In his youth he was a student of medicine at Gottingen, where at the age of twenty-three he took his first degree. He was by nature and from his boyhood a devotee of science. For about ten years he practiced his profession, but continued his studies with indefatigable zeal. The investigations of Pasteur had already filled Europe with applause when Koch, following on the same lines of scientific exploration, began to enlarge the borders of knowledge. He became a bacteriologist of the first rank. He began to investigate the causes and nature of contagion; but as late as 1876 his name was still unknown in the cyclopaedias.

Koch was twenty-one years the junior of Pasteur; but his enthusiasm and genius now bore him rapidly to a fame as great as that of his predecessor. His first remarkable achievement was a demonstration of the cause and cure of splenic fever in cattle. He showed, just as Pasteur had done in similar cases, that the plague in question was due to the specific poison of a bacterium, and that the disease might be cured by inoculation against it. This he proceeded to do, and the demonstration and good work brought him to the attention of the old Emperor. Dr. Koch was made a member of the Imperial Board of Health in Berlin.

A greater discovery was already at the door. Dr. Koch began a careful investigation into the nature of consumption. His discovery of the germ of splenic fever, and that of chicken cholera, as well as the general results in this direction in other laboratories of Europe, led him to the conjecture that consumption also is a zymotic or bacterial disease. His inquiry into this subject began in 1879, and extended to March of 1882. On that day, in a paper before the Physiological Society of Berlin, he announced the discovery of the _tubercle bacillus_. He was able to demonstrate the existence of the germ of consumption, and to describe its methods of life, as well as the character of his ravages.

Here then at last was laid bare the true origin of the most fatal disease which has ever afflicted mankind. He who has not informed himself with respect to the almost universal prevalence of consumption among the nations of the earth, or taken note of the mortality from that dreaded enemy, by which nearly one-sixth of the human race sooner or later perishes, will not have realized the awful character of this enemy. To attack such a foe, to force him into a corner, even as Siegfried did the Grendel in his cavern, was an achievement of which the greatest of mankind might well be proud.

The discovery of the bacillus of consumption by no means a.s.sured the cure of the disease; but it foretokened the time when a cure would be found. This prophecy, though it has not yet been clearly fulfilled, is, in the closing years of the century, in process of fulfillment.

The enemy does not readily yield; but such has been the gain in the contest that already within the last twenty years the mortality from consumption of the lungs has fallen off more than forty per cent! Much of this gain has been made by the reviving confidence of human beings that sooner or later tuberculosis would be destroyed. Hygiene has done its part; and other circ.u.mstances have conduced to the same result.

Though neither Dr. Koch nor any other man living has been able as yet positively to meet and vanquish consumption in open battle, yet the goblin has in a measure been robbed of his terrors. He is no longer boastful and victorious over the human race.

After the discovery of the tubercle bacillus, the fame of Robert Koch became world-wide. In the following year he was made a privy councilor, and was placed in charge of an expedition organized by the German government to go into Egypt and India for the investigation of the causes of Asiatic cholera. The expedition was engaged in this work for nearly a year. Koch pursued his usual careful method of scientific experimentation. He exposed himself to the contagion of cholera, but his science and fine const.i.tution stood him well in hand, and he returned unharmed.

It was in May of 1884 that he was able to announce the discovery of the _coma bacillus_, that is, the bacterium of cholera. Here, again he had the enemy at bay. For long ages the Asiatic plague had ravaged the countries of the East with little hindrance to its spread or fatality.

The disease would appear as an epidemic at intervals and sweep all before it. The wave of death would roll on westward from country to country, until it would subside, as if by exhaustion, in the far west.

Two or three times within the century cholera had been fatally scattered through American cities. It had spread westward along the rivers of the Ohio and Mississippi valleys, and into country districts, where villages and hamlets were decimated.

The discovery of Koch was a virtual proclamation that this ruin of mankind from the Asiatic plague should cease. The knowledge that the disease was due to a living bacterium, that without the germ and the spread of the germ the plague could not exist, was a virtual announcement that in the civilized countries it should _not_ any longer exist.

The discoverer was now set high in the estimation of mankind. Imperial Germany best of all countries rewards its benefactors. France is fascinated with adventure; Great Britain with slaughter; America with bare political battles; but Germany sees the true thing, and rewards it. Koch was immediately placed beyond want by his government, and t.i.tles and honors came without stint.

The Empire would fain have such a man at the seat of power. Dr. Koch was, in 1885, made a professor in the University of Berlin. The new chair of Hygiene was created for him, and he was made Director of the Hygienic Inst.i.tute. It was in this capacity that armed with influence and authority and having the resources of the government virtually at his disposal, he directed in the great scientific work by which a bulwark against cholera was drawn almost literally across Europe, and was defended as if with the mounted soldiery of science and humanity.

True enough, cholera managed to plant itself in Italy in 1886, and in Hamburg in 1892, and the plague was scattered into several German towns. But it came to Hamburg by water, not by land. It did there during the summer a dreadful work, but the battle was the Waterloo of the enemy. Not again while the present order continues will it be possible for the dreaded epidemic to get the mastery of a great German city.

It was to be antic.i.p.ated that Dr. Koch's discovery of the tubercle bacillus would lead him on to the discovery of a cure for tuberculosis. Very naturally his thought on this subject was borne in the direction of inoculation. That method had been used by Pasteur and by himself in the case of other infectious diseases. Why should it not be employed in consumption? If the "domestication," so-called, of the virus of splenic fever and the use of the modified poison as an antiseptic preventive of the disease was successful, as it had been proved to be, why should this not be done with the attenuated virus of consumption?

The last five years of the ninth decade were spent by Dr. Koch in experimentation on this subject. He found that the tubercular poison might be treated in the same manner as the poison of other infectious diseases. He experimented with methods for domesticating the bacillus of consumption, and reached successful results. On the fourteenth of November, 1890, he published in a German medical magazine at Berlin a communication on a possible remedy for tuberculosis. He had prepared a sort of lymph suitable for hypodermic injection, and with this had experimented on a form of _external_ tuberculosis called lupus. This disease is a consumption of the skin and adjacent tissues. It is a malady almost as dreadful as consumption of the lungs, but is by no means frequent in its occurrence. It is found only at rare intervals by the medical pract.i.tioner.

Dr. Koch had demonstrated that lupus is a true tuberculosis--that the germ which produces it is the same bacillus which produces consumption of the lungs. He accordingly directed his effort to cases of lupus, treating the patients with hypodermic injections which he had prepared from the modified form of the tubercular poison. He was successful in the treatment, and was able to announce, to the joy of the world, that he had discovered a cure for lupus; and the announcement went so far as to express a belief in the salutary character of the remedy in the treatment of consumption of the lungs.

Dr. Koch, however, with the usual caution of the true men of science, did not announce his tuberculin, or lymph, as a cure for pulmonary consumption. He did not even declare that it was positively a remedy for the other forms of tuberculosis, but did announce his cure of cases of lupus by the agent which he had prepared. The world, after its manner, leaped at conclusions, and the newspapers of two continents, in their usual office of disseminating ignorance, trumpeted Koch's discovery as the end of tubercular consumption.

In January of 1891, Dr. Koch published to the world the composition of his remedy. It consists of a glycerine extract prepared by the cultivation of tubercle bacilli. The lymph contains, as it were, the poisonous matter resulting from the life and activity of the tubercle bacterium. The fluid is used by hypodermic injection, and when so administered produces both a general and local reaction. The system is powerfully affected. A sense of weariness comes on. The breathing is labored. Nausea ensues; and a fever supervenes which lasts for twelve or fifteen hours. It is now known that the action of the remedy is not directly against the tubercle bacilli, but rather against the affected tissue in which they exist. This tissue is destroyed and thrown off by the agency of the lymph; being destroyed, it is eliminated and cast out, carrying with it the bacteria on which the disease depends.

The results which have followed the administration of Koch's lymph for consumption of the lungs have not met the expectation of the public; but something has been accomplished. Ignorant enthusiasm has meanwhile subsided, and scientific men in both Europe and America are pressing the inquiry in a way which promises in due time the happiest results.

ACHIEVEMENTS IN SURGERY.

It will not do to disparage the work of the ancients. The old world, long since fallen below the horizon of the past, had races of men and individuals who might well be compared with the greatest of to-day. In a general way, the ancients were great as thinkers and weak as scientists. They were great in the fine arts and weak in the practical arts. This is true of the Hindus, the Egyptians, the Greeks, the Romans, even of the Aztecs and the Peruvians.

The art work of these old peoples, whether in sculpture, painting or poetry, surpa.s.sed, if it did not eclipse, corresponding periods of modern times. In some of the practical arts the old races were proficient. In architecture, which combines the aesthetic and practical elements, the man of antiquity was at least the equal of the man of the present. In one particular art--a sort of humanitarian profession based on natural science and directed to the preservation of life--the ancients had a measure of proficiency. This art was surgery. The surgeon was even from the beginning, and he will no doubt be even to the end.

The great advance which has been made in surgical science and practice is shown in two ways: first, in a great increase of courage, by which the surgeon has been led on to the performance of operations that were hitherto considered rash, audacious or impossible; and secondly, by the immunity which the surgeon has gained in the treatment of wounds through the increased knowledge he possesses of putrefaction and the means of preventing it. It were hard to say whether the surgeon's increase of skill and courage in performing operations has equalled his increased skill in the after treatment of wounds.

These improvements have all proceeded from scientific investigation.

They have come of the application of scientific methods to the treatment of surgical diseases. With the investigations of Pasteur and the development of the science of bacteriology, it was seen at a glance how large an influence such investigation must have in the work of the surgeon. The publication of Tyndall's "Essays on the Floating Matter of the Air in Relation to Putrefaction and Infection,"

in 1881, gave a great impulse to the new practice; but that practice had been already confirmed by the great and original work of Sir Joseph Lister, an English surgeon who as early as 1860 had introduced the antiseptic method of bandaging.

It is within the last forty years that the greatest marvels of modern surgery have been performed. It would seem that no part of the human body is now beyond the reach of surgical remedy. Almost every year has witnessed some new and daring invasion of the fortress of life with a view to saving it. Old opinions with respect to what parts of the human economy are really vital have been abolished; and a new concept of the relation of life to organism has prevailed.

Until recently it was supposed that the peritoneal cavity and the organs contained therein, such as the stomach, the liver, the bowels, etc., could not be entered by the surgeon without the certain result of death. To do so at the present time is the daily experience in almost every great hospital. The complexity of civilization has inflicted all manner of hurts on the human body, and the malignity of disease has spared no part. It was supposed that the cranial cavity could not be entered or repaired without producing fatal results. It was taken for granted that certain organs could not be touched, much less treated capitally, without destroying the subject's life. But one exploration has followed another and one successful adventure has been succeeded by another still more successful until the surgeon's work is at the present time performed within a sphere that was until recently supposed to be entirely beyond his reach.

As to the liver, that great organ is freely examined and is treated surgically with considerable freedom. This is true also of the stomach, which until recently was supposed to be entirely beyond the surgeon's touch. Within the last two decades sections of the stomach have been made and parts of the organ removed. Not a few cases are recorded in which subjects have fully recovered after the removal of a part of the stomach. Sections of the intestinal ca.n.a.l have also been made with entire success. Several inches of that organ have in some cases been entirely removed, with the result of recovery! The spleen has been many times removed; but it has been recently noted that a decline in health and probably death at a not distant date generally follow this operation.

The disease called appendicitis has either in our times become wonderfully frequent or else the improved methods of diagnosis have made us acquainted with what has long been one of the princ.i.p.al maladies of mankind. The _appendix vermiformis_ seems to be a useless remnant of anatomical structure transmitted to us from a lower animal condition. At least such is the interpretation which scientists generally give to this hurtful and dangerous tube-like blind channel in connection with the bowels. That it becomes easily inflamed and is the occasion of great loss of life can not be doubted. Its removal by surgical operation is now regarded as a simple process which even the unlearned surgeon, if he be careful and talented, may safely perform.

The surgical treatment of appendicitis has become so common as to attract little or no notice from the profession. Even the country neighborhood no longer regards such a piece of surgery as sensational.

The use of surgical means in the cure, that is the removal, of tumors, both external and internal, has been greatly extended and perfected.

The surgeon now carries a quick eye for the tumor and a quick remedy for it. In nearly all cases in which it has not become const.i.tutional he effects a speedy cure with the knife. The cancerous part is cut away. It has been observed that as the recent mortality from consumption has decreased cancerous diseases have become more frequently fatal. Whether or not there be anything vicarious in the action of these two great maladies we know not; but statistics show that since the beginning of Pasteur's discoveries the one disease has diminished and the other increased in almost a corresponding ratio.

Meanwhile, however, surgery has opposed itself not only to cancers but to all kinds of tumors, until danger from these sores has been greatly lessened. The removal of internal tumors such as the ovarian, is no longer, except in complicated and neglected cases, a matter of serious import. Such work is performed in almost every country town, and the amount of human life thus rescued from impending death is very great.