The confusion of ideas on the origin of contagious and epidemic diseases was about to be suddenly enlightened; Pasteur had now taken up the study of the disease known as charbon or splenic fever. This disease was ruining agriculture; the French provinces of Beauce, Brie, Burgundy, Nivernais, Berry, Champagne, Dauphiné and Auvergne, paid a formidable yearly tribute to this mysterious scourge. In the Beauce, for instance, twenty sheep out of every hundred died in one flock; in some parts of Auvergne the proportion was ten or fifteen per cent., sometimes even twenty-five, thirty-five, or fifty per cent. At Provins, at Meaux, at Fontainebleau, some farms were called charbon farms; elsewhere, certain fields or hills were looked upon as accursed and an evil spell seemed to be thrown over flocks bold enough to enter those fields or ascend those hills. Animals stricken with this disease almost always died in a few hours; sheep were seen to lag behind the flock, with drooping head, shaking limbs and gasping breath; after a rigor and some sanguinolent evacuations, occurring also through the mouth and nostrils, death supervened, often before the shepherd had had time to notice the attack. The carcase rapidly became distended, and the least rent in the skin gave issue to a flow of black, thick and viscid blood, hence the name of anthrax given to the disease. It was also called splenic fever, because necropsy showed that the spleen had assumed enormous dimensions; if that were opened, it presented a black and liquid pulp. In some places the disease assumed a character of extreme virulence; in the one district of Novgorod, in Russia, 56,000 head of cattle died of splenic infection between 1867 and 1870. Horses, oxen, cows, sheep, everything succumbed, as did also 528 persons, attacked by the contagion under divers forms; a{258} pin prick or a scratch is sufficient to inoculate shepherds, butchers, knackers or farmers with the malignant pustule. Though a professor at the Alfort Veterinary School, M. Delafond, did point out to his pupils as far back as 1838 that charbon blood contained “little rods,” as he called them; it was only looked upon by himself and them as a curiosity with no scientific importance. Davaine, when he—and Rayer as well—recognized in 1850 those little filiform bodies in the blood of animals dying of splenic fever, he too merely mentioned the fact, which seemed to him of so little moment that he did not even report it in the first notice of his works edited by himself.
It was only eleven years later that Davaine—struck, as he himself gladly acknowledged, by reading Pasteur’s paper on the butyric ferment, the little cylindrical rods of which offer all the characteristics of vibriones or bacteria—asked himself whether the filiform corpuscles seen in the blood of the charbon victims might not act after the manner of ferments and be the cause of the disease. In 1863, a medical man at Dourdan, whose neighbour, a farmer, had lost twelve sheep of charbon in a week, sent blood from one of these sheep to Davaine, who hastened to inoculate some rabbits with this blood. He recognized the presence of those little transparent and motionless rods which he called bacteridia (a diminutive of bacterium, or rod-shaped vibriones). It might be thought that the cause of the evil was found, in other words that the relation between those bacteridia and the disease which had caused death could not be doubted. But two professors of the Val de Grace, Jaillard and Leplat; refuted these experiments.
They had procured, in the middle of the summer, from a knacker’s yard near Chartres, a little blood from a cow which had died of anthrax, and they inoculated some rabbits with it. The rabbits died, but without presenting any bacteridia. Jaillard and Leplat therefore affirmed that splenic fever was not an affection caused by parasites, that the bacteridium was an epiphenomenon of the disease and could not be looked upon as the cause of it.
Davaine, on repeating Jaillard and Leplat’s experiments, found a new interpretation; he alleged that the disease they had inoculated was not anthrax. Then Jaillard and Leplat obtained a little diseased sheep’s blood from M. Boutet, a veterinary surgeon at Chartres, and tried that instead of co{259}w’s blood. The result was identical: death ensued, but no bacteridia. Were there then two diseases?
Others made observations in their turn. It occurred to a young German physician, Dr. Koch, who in 1876 was beginning his career in a small village in Germany, to seek a culture medium for the bacteridium. A few drops of aqueous humour, collected in the eyes of oxen or of rabbits, seemed to him favourable. After a few hours of this nutrition the rods seen under the microscope were ten or twenty times larger than at first; they lengthened immoderately, so as to cover the whole slide of the microscope, and might have been compared to a ball of tangled thread. Dr. Koch examined those lengths, and after a certain time noticed little spots here and there looking like a punctuation of spores. Tyndall, who knew how to secure continuous attention by a variety of comparisons, said at a scientific conference in Glasgow a few months later that those little ovoid bodies were contained within the envelope of the filament like peas in their pods. It is interesting to note that Pasteur, when he studied, in connection with silkworm diseases, the mode of reproduction of the vibriones of flachery, had seen them divide into spores similar to shining corpuscles; he had demonstrated that those spores, like seeds of plants, could revive after a lapse of years and continue their disastrous work. The bacterium of charbon, or bacillus anthracis as it now began to be called, reproduced itself in the same way, and, when inoculated by Dr. Koch into guinea-pigs, rabbits and mice, provoked splenic fever as easily and inevitably as blood from the veins of an animal that had died of the disease. Bacilli and spores therefore yielded the secret of the contagion, and it seemed that the fact was established, when Paul Bert, in January, 1877, announced to the Société de Biologie that it was “possible to destroy the bacillus anthracis in a drop of blood by compressed oxygen, to inoculate what remained, and to reproduce the disease and death without any trace of the bacteridium ... Bacteridia,” he added, “are therefore neither the cause nor the necessary effect of splenic fever, which must be due to a virus.”
Pasteur tackled the subject. A little drop of the blood of an animal which had died of anthrax—a microscopic drop—was laid, sown, after the usual precautions to ensure purity, in a sterilized balloon which contained neutral or slightly alkaline urine. The culture medium might equally be common house{260}hold broth, or beer-yeast water, either of them neutralized by potash. After a few hours, a sort of flake was floating in the liquid; the bacteridia could be seen, not under the shape of short broken rods, but with the appearance of filaments, tangled like a skein; the culture medium being highly favourable, they were rapidly growing longer. A drop of that liquid, abstracted from the first vessel, was sown into a second vessel, of which one drop was again placed into a third, and so on, until the fortieth flask; the seed of each successive culture came from a tiny drop of the preceding one. If a drop from one of those flasks was introduced under the skin of a rabbit or guinea-pig, splenic fever and death immediately ensued, with the same symptoms and characteristics as if the original drop of blood had been inoculated. In the presence of the results from those successive cultures, what became of the hypothesis of an inanimate substance contained in the first drop of blood? It was now diluted in a proportion impossible to imagine. It would therefore be absurd, thought Pasteur, to imagine that the last virulence owed its power to a virulent agent existing in the original drop of blood; it was to the bacteridium, multiplied in each culture, and to the bacteridium alone, that this power was due; the life of the bacteridium had made the virulence. “Anthrax is therefore” Pasteur declared, “the disease of the bacteridium, as trichinosis is the disease of the trichina, as itch is the disease of its special acarus, with this circumstance, however, that, in anthrax, the parasite can only be seen through a microscope, and very much enlarged.” After the bacteridium had presented those long filaments, within a few hours, two days at the most, another spectacle followed; amidst those filaments, appeared the oval shapes, the germs, spores or seeds, pointed out by Dr. Koch. Those spores, sown in broth, reproduced in their turn the little packets of tangled filaments, the bacteridia. Pasteur reported that “one single germ of bacteridium in the drop which is sown multiplies during the following hours and ends by filling the whole liquid with such a thickness of bacteridia that, to the naked eye, it seems that carded cotton has been mixed with the broth.”
M. Chamberland, a pupil who became intimately associated with this work on anthrax, has defined as follows what Pasteur had now achieved: “By his admirable process of culture outside organism, Pasteur shows that the rods which exist in the blood, and for which he has preserved the name of bacteridia{261} given them by Davaine, are living beings capable of being indefinitely reproduced in appropriate liquids, after the manner of a plant multiplied by successive cuttings. The bacterium does not reproduce itself only under the filamentous form, but also through spores or germs, after the manner of many plants which present two modes of reproduction, by cuttings and by seeds.” The first point was therefore settled. The ground suspected and indicated by Davaine was now part of the domain of science, and preserved from any new attacks.
Yet Jaillard and Leplat’s experiments remained to be explained: how had they provoked death through the blood of a splenic fever victim and found no bacteridia afterwards? It was then that Pasteur, guided, as Tyndall expressed it, by “his extraordinary faculty of combining facts with the reasons of those facts,” placed himself, to begin with, in the conditions of Jaillard and Leplat, who had received, during the height of the summer, some blood from a cow and a sheep which had died of anthrax, that blood having evidently been abstracted more than twenty-four hours before the experiment. Pasteur, who had arranged to go to the very spot, the knacker’s yard near Chartres, and himself collect diseased blood, wrote to ask that the carcases of animals which had died of splenic fever should be kept for him for two or three days.
He arrived on June 13, 1877, accompanied by the veterinary surgeon, M. Boutet. Three carcases were awaiting him: that of a sheep which had been dead sixteen hours, that of a horse whose death dated from the preceding day, and that of a cow which must have been dead for two or three days, for it had been brought from a distant village. The blood of the recently diseased sheep contained bacteridia of anthrax only. In the blood of the horse, putrefaction vibriones were to be found, besides the bacteridia, and those vibriones existed in a still greater proportion in the blood of the cow. The sheep’s blood, inoculated into guinea-pigs, provoked anthrax with pure bacteridia; that of the cow and of the horse brought a rapid death with no bacteridia.
Henceforth what had happened in Jaillard and Leplat’s experiments, and in the incomplete and uncertain experiments of Davaine, became simple and perfectly clear to Pasteur, as well as the confusion caused by another experimentalist who had said his say ten years after the discussions of Jaillard, Leplat and Davaine.{262}
This was a Paris veterinary surgeon, M. Signol. He had written to the Academy of Sciences that it was enough that a healthy animal should be felled, or rather asphyxiated, for its blood, taken from the deeper veins, to become violently virulent within sixteen hours. M. Signol thought he had seen motionless bacteridia similar to the bacillus anthracis; but those bacteridia, he said, were incapable of multiplying in the inoculated animals. Yet the blood was so very virulent that animals rapidly succumbed in a manner analogous to death by splenic fever. A Commission was nominated to ascertain the facts; Pasteur was made a member of it, as was also his colleague Bouillaud—still so quick and alert, in spite of his eighty years, that he looked less like an old man than like a wrinkled young man—and another colleague, twenty years younger, Bouley, the first veterinary surgeon in France who had a seat at the Institute. The latter was a tall, handsome man, with a somewhat military appearance, and an expression of energetic good humour which his disposition fully justified. He was eager to help in the propagation of new ideas and discoveries, and soon, with eager enthusiasm, placed his marked talents as a writer and orator at Pasteur’s disposal.
On the day when the Commission met, M. Signol showed the carcase of a horse, which he had sacrificed for this experiment, having asphyxiated it when in excellent health. Pasteur uncovered the deep veins of the horse and showed to Bouley, and also to Messrs. Joubert and Chamberland, a long vibrio, so translucid as to be almost invisible, creeping, flexible, and which, according to Pasteur’s comparison, slipped between the globules of the blood as a serpent slips between high grasses; it was the septic vibrio. From the peritoneum, where it swarms, that vibrio passes into the blood a few hours after death; it represents the vanguard of the vibriones of putrefaction. When Jaillard and Leplat had asked for blood infected with anthrax, they had received blood which was at the same time septic. It was septic?mia (so prompt in its action that inoculated rabbits or sheep perish in twenty-four or thirty-six hours) that had killed Jaillard and Leplat’s rabbits. It was also septic?mia, provoked by this vibrio (or its germs, for it too has germs), that M. Signol had unknowingly inoculated into the animals upon which he experimented. Successive cultures of that septic vibrio enabled Pasteur to show, as he had done for the bacillus anthracis, that one drop of those cul{263}tures caused septic?mia in an animal. But, while the bacillus anthracis is a?robic, the septic vibrio, being ana?robic, must be cultivated in a vacuum, or in carbonic acid gas. And, cultivating those bacteridia and those vibriones with at least as much care as a Dutchman might give to rare tulips, Pasteur succeeded in parting the bacillus anthracis and the septic vibrio when they were temporarily associated. In a culture in contact with air, only bacteridia developed, in a culture preserved from air, only the septic vibrio.
What Pasteur called “the Paul Bert fact” now alone remained to be explained; this also was simple. The blood Paul Bert had received from Chartres was of the same quality as that which Jaillard and Leplat had had; that is to say already septic. If filaments of bacillus anthracis and of septic vibriones perish under compressed oxygen, such is not the case with the germs, which are extremely tenacious; they can be kept for several hours at a temperature of 70° C., and even of 95° C. Nothing injures them, neither lack of air, carbonic acid gas nor compressed oxygen. Paul Bert, therefore, killed filamentous bacteridia under the influence of high pressure; but, as the germs were none the worse, those germs revived the splenic fever. Paul Bert came to Pasteur’s laboratory, ascertained facts and watched experiments. On June 23, 1877, he hastened to the Société de Biologie and proclaimed his mistake, acting in this as a loyal Frenchman, Pasteur said.
In spite of this testimony, and notwithstanding the admiration conceived for Pasteur by certain medical men—notably H. Gueneau de Mussy, who published in that very year (1877) a paper on the theory of the contagium germ and the application of that theory to the etiology of typhoid fever—the struggle was being continued between Pasteur and the current medical doctrines. In the long discussion which began at that time in the Académie de Médecine on typhoid fever, some masters of medical oratory violently attacked the germ theory, proclaiming the spontaneity of living organism. Typhoid fever, they said, is engendered by ourselves within ourselves. Whilst Pasteur was convinced that the day would come—and that was indeed the supreme goal of his life work—when contagious and virulent diseases would be effaced from the preoccupations, mournings and anxieties of humanity, and when the infinitesimally small, known, isolated and studied, would at last be vanquished, his ideas were called Utopian dreams.{264}
The old professors, whose career had been built on a combination of theories which they were pleased to call medical truth, dazed by such startling novelties, endeavoured, as did Piorry, to attract attention to their former writings. “It is not the disease, an abstract being,” said Piorry, “which we have to treat, but the patient, whom we must study with the greatest care by all the physical, chemical and clinical means which Science offers.”
The contagion which Pasteur showed, appearing clearly in the disorders visible in the carcases of inoculated guinea-pigs, was counted as nothing. As to the assimilation of a laboratory experiment on rabbits and guinea-pigs to what occurred in human pathology, it may be guessed that it was quite out of the question for men who did not even admit the possibility of a comparison between veterinary medicine and the other. It would be interesting to reconstitute these hostile surroundings in order to appreciate the efforts of will required of Pasteur to enable him to triumph over all the obstacles raised before him in the medical and the veterinary world.
The Professor of Alfort School, Colin, who had, he said, made 500 experiments on anthrax within the last twelve years, stated, in a paper of seventeen pages, read at the Academy of Medicine on July 31, that the results of Pasteur’s experiments had not the importance which Pasteur attributed to them. Among many other objections, one was considered by Colin as a fatal one—the existence of a virulent agent situated in the blood, besides the bacteridia.
Bouley, who had just communicated to the Academy of Sciences some notes by M. Toussaint, professor at the Toulouse veterinary school, whose experiments agreed with those of Pasteur, was nevertheless a little moved by Colin’s reading. He wrote in that sense to Pasteur, who was then spending his holidays in the Jura. Pasteur addressed to him an answer as vigorous as any of his replies at the Academy.
“Arbois, August 18, 1877.—My dear colleague ... I hasten to answer your letter. I should like to accept literally the honour which you confer upon me by calling me ‘your master,’ and to give you a severe reprimand, you faithless man, who would seem to have been shaken by M. Colin’s reading at the Académie des Sciences, since you are still holding forth on the possibility of a virulent agent, and since your uncertainties seem to be appeased by a new{265} notice, read by yourself, last Monday, at the Académie des Sciences.
“Let me tell you frankly that you have not sufficiently imbibed the teaching contained in the papers I have read, in my own name and in that of M. Joubert, at the Académie des Sciences and at the Academy of Medicine. Can you believe that I should have read those papers if they had wanted the confirmation you mention, or if M. Colin’s contradictions could have touched them? You know what my situation is, in these grave controversies; you know that, ignorant as I am of medical and veterinary knowledge, I should immediately be taxed with presumption if I had the boldness to speak without being armed for struggle and for victory! All of you, physicians and veterinary surgeons, would quite reasonably fall upon me if I brought into your debates a mere semblance of proof.
“How is it that you have not noticed that M. Colin has travestied—I should even say suppressed—because it hindered his theory, the important experiment of the successive cultures of the bacteridium in urine?
“If a drop of blood, infected with anthrax, is mixed with water, with pure blood or with humour from the eye, as was done by Davaine, Koch and M. Colin himself, and some of that mixture is inoculated and death ensues, doubt may remain in the mind as to the cause of virulence, especially since Davaine’s well-known experiments on septic?mia. Our experiment is very different....”
And Pasteur showed how, from one artificial culture to another, he reached the fiftieth, the hundredth, and how a drop of this hundredth culture, identical with the first, could bring about death as certainly as a drop of infected blood.
Months passed, and—as Pasteur used to wish in his youth that it might be—few passed without showing one step forward. In a private letter to his old Arbois school-fellow, Jules Vercel, he wrote (February 11, 1878): “I am extremely busy; at no epoch of my scientific life have I worked so hard or been so much interested in the results of my researches, which will, I hope, throw a new and a great light on certain very important branches of medicine and of surgery.”
 
In the face of those successive discoveries, every one had a word to say. This accumulation of facts was looked down upon by that category of people who borrow assurance from a mix{266}ture of ignorance and prejudice. Others, on the other hand, amongst whom the greatest were to be found, proclaimed that Pasteur’s work was immortal and that the word “theory” used by him should be changed into that of “doctrine.” One of those who thus spoke, with the right given by full knowledge, was Dr. Sédillot, whose open and critical mind had kept him from becoming like the old men described by Sainte Beuve as stopping their watch at a given time and refusing to recognize further progress. He was formerly Director of the Army Medical School at Strasburg, and had already retired in 1870, but had joined the army again as volunteer surgeon. It will be remembered that he had written from the Hagueneau ambulance to the Académie des Sciences—of which he was a corresponding member—to call the attention of his colleagues to the horrors of purulent infection, which defied his zeal and devotion.
No one followed Pasteur’s work with greater attention than this tall, sad-looking old man of seventy-four; he was one of those who had been torn away from his native Alsace, and he could not get over it. In March, 1878, he read a paper to the Academy, entitled “On the Influence of M. Pasteur’s Work on Medicine and Surgery.”
Those discoveries, he said, which had deeply modified the state of surgery, and particularly the treatment of wounds, could be traced back to one principle. This principle was applicable to various facts, and explained Lister’s success, and the fact that certain operations had become possible, and that certain cases, formerly considered hopeless, were now being recorded on all sides. Real progress lay there. Sédillot’s concluding paragraph deserves to be handed down as a comment precious from a contemporary: “We shall have seen the conception and birth of a new surgery, a daughter of Science and of Art, which will be one of the greatest wonders of our century, and with which the names of Pasteur and Lister will remain gloriously connected.”
In that treatise, Sédillot invented a new word to characterize all that body of organisms and infinitely small vibriones, bacteria, bacteridia, etc.; he proposed to designate them all under the generic term of microbe. This word had, in Sédillot’s eyes, the advantage of being short and of having a general signification. He however felt some scruple before using it, and consulted Littré, who replied on February 26,{267} 1878: “Dear colleague and friend, microbe and microbia are very good words. To designate the animalcul?e I should give the preference to microbe, because, as you say, it is short, and because it leaves microbia, a feminine noun, for the designation of the state of a microbe.”
Certain philologists criticized the formation of the word in the name of the Greek language. Microbe, they said, means an animal with a short life, rather than an infinitesimally small animal. Littré gave a second testimonial to the word microbe—
“It is true,” he wrote to Sédillot, “that μιχρ?βιο? and μαχρ?βιο? probably mean in Greek short-lived and long-lived. But, as you justly remark, the question is not what is most purely Greek, but what is the use made in our language of the Greek roots. Now the Greek has β?ο?, life, βιο?ν, to live, βιο??, living, the root of which may very well figure under the form of bi, bia with the sense living, in a?robia, ana?robia and microbe. I should advise you not to trouble to answer criticisms, but let the word stand for itself, which it will no doubt do.” Pasteur, by adopting it, made the whole world familiar with it.
Though during that month of March, 1878, Pasteur had had the pleasure of hearing Sédillot’s prophetic words at the Académie des Sciences, he had heard very different language at the Académie de Médecine. Colin of Alfort, from the isolated corner where he indulged in this misanthropy, had renewed his criticisms of Pasteur. As he spoke unceasingly of a state of virulent anthrax devoid of bacteridia, Pasteur, losing patience, begged of the Académie to nominate a Commission of Arbitration.
“I desire expressly that M. Colin should be urged to demonstrate what he states to be the fact, for his assertion implies another, which is that an organic matter, containing neither bacteridia nor germs of bacteridia, produces within the body of a living animal the bacteridia of anthrax. This would be the spontaneous generation of the bacillus anthracis!”
Colin’s antagonism to Pasteur was such that he contradicted him in every point and on every subject. Pasteur having stated that birds, and notably hens, did not take the charbon disease, Colin had hastened to say that nothing was easier than to give anthrax to hens; this was in July, 1877. Pasteur, who was at that moment sending Colin some samples of bacteridia{268} culture which he had promised him, begged that he would kindly bring him in exchange a hen suffering from that disease, since it could contract it so easily.
Pasteur told the story of this episode in March, 1878; it was an amusing interlude in the midst of those technical discussions. “At the end of the week, I saw M. Colin coming into my laboratory, and, even before I shook hands with him, I said to him: ‘Why, you have not brought me that diseased hen?’—‘Trust me,’ answered M. Colin, ‘you shall have it next week.’—I left for the vacation; on my return, and at the first meeting of the Academy which I attended, I went to M. Colin and said, ‘Well, where is my dying hen?’ ‘I have only just begun experimenting again,’ said M. Colin; ‘in a few days I will bring you a hen suffering from charbon.’—Days and weeks went by, with fresh insistence on my part and new promises from M. Colin. One day, about two months ago, M. Colin owned to me that he had been mistaken, and that it was impossible to give anthrax to a hen. ‘Well, my dear colleague,’ I said to him, ‘I will show you that it is possible to give anthrax to hens; in fact, I will one day myself bring you at Alfort a hen which shall die of charbon.’
“I have told the Academy this story of the hen M. Colin had promised in order to show that our colleague’s contradiction of our observations on charbon had never been very serious.”
Colin, after speaking about several other things, ended by saying: “I regret that I have not until now been able to hand to M. Pasteur a hen dying or dead of anthrax. The two that I had bought for that purpose were inoculated several times with very active blood, but neither of them has fallen ill. Perhaps the experiment might have succeeded afterwards, but, one fine day, a greedy dog prevented that by eating up the two birds, whose cage had probably been badly closed.” On the Tuesday which followed this incident, the passers-by were somewhat surprised to see Pasteur emerging from the Ecole Normale, carrying a cage, within which were three hens, one of them dead. Thus laden, he took a fiacre, and drove to the Académie de Médecine, where, on arriving, he deposited this unexpected object on the desk. He explained that the dead hen had been inoculated with charbon two days before, at twelve o’clock on the Sunday, with five drops of yeast water employed as a nutritive liquid for pure bacteridium germs, and{269} that it had died on the Monday at five o’clock, twenty-nine hours after the inoculation. He also explained, in his own name, and in the names of Messrs. Joubert and Chamberland, how in the presence of the curious fact that hens were refractory to charbon, it had occurred to them to see whether that singular and hitherto mysterious preservation did not have its cause in the temperature of a hen’s body, “higher by several degrees than the temperature of the body of all the animal species which can be decimated by charbon.”
This preconceived idea was followed by an ingenious experiment. In order to lower the temperature of an inoculated hen’s body, it was kept for some time in a bath, the water covering one-third of its body. When treated in that way, said Pasteur, the hen dies the next day. “All its blood, spleen, lungs, and liver are filled with bacilli anthracis susceptible of ulterior cultures either in inert liquids or in the bodies of animals. We have not met with a single exception.”
As a proof of the success of the experiment, the white hen lay on the floor of the cage. As people might be forthcoming, even at the Academy, who would accuse the prolonged bath of having caused death, one of the two living hens, a gray one, who was extremely lively, had been placed in the same bath, at the same temperature and during the same time. The third one, a black hen, also in perfect health, had been inoculated at the same time as the white hen, with the same liquid, but with ten drops instead of five, to make the comparative result more convincing; it had not been subjected to the bath treatment. “You can see how healthy it is,” said Pasteur; “it is therefore impossible to doubt that the white hen died of charbon; besides, the fact is proved by the bacteridia which fill its body.”
A fourth experiment remained to be tried on a fourth hen, but the Academy of Medicine did not care to hold an all-night sitting. Time lacking, it was only done later, in the laboratory. Could a hen, inoculated of charbon and placed in a bath, recover and be cured merely by being taken out of its bath? A hen was taken, inoculated and held down a prisoner in a bath, its feet fastened to the bottom of the tub, until it was obvious that the disease was in full progress. The hen was then taken out of the water, dried, and wrapped up in cotton wool and placed in a temperature of 35° C. The bac{270}teridia were reabsorbed by the blood, and the hen recovered completely.
This was, indeed, a most suggestive experiment, proving that the mere fall of temperature from 42° C. (the temperature of hens) to 38° C. was sufficient to cause a receptive condition; the hen, brought down by immersion to the temperature of rabbits or guinea-pigs, became a victim like them.
Between Sédillot’s enthusiasm and Colin’s perpetual contradiction, many attentive surgeons and physicians were taking a middle course, watching for Pasteur’s results and ultimately accepting them with admiration. Such was the state of mind of M. Lereboullet, an editor of the Weekly Gazette of Medicine and Surgery, who wrote in an account of the Académie de Médecine meeting that “those facts throw a new light on the theory of the genesis and development of the bacillus anthracis. They will be ascertained and verified by other experimentalists, and it seems very probable that M. Pasteur, who never brings any premature or conjectural assertion to the academic tribune, will deduce from them conclusions of the greatest interest concerning the etiology of virulent diseases.”
But even to those who admired Pasteur as much as did M. Lereboullet, it did not seem that such an important part should immediately be attributed to microbes. Towards the end of his report (dated March 22, 1878) he reminded his readers that a discussion was open at the Académie de Médecine, and that the surgeon, Léon Le Fort, did not admit the germ theory in its entirety. M. Le Fort recognized “all the services rendered to surgery by laboratory studies, chiefly by calling attention to certain accidents of wounds and sores, and by provoking new researches with a view to improving methods of dressing and bandaging.” “Like all his colleagues at the Academy, and like our eminent master, M. Sédillot,” added M. Lereboullet, “M. Le Fort renders homage to the work of M. Pasteur; but he remains within his rights as a practitioner and reserves his opinion as to its general application to surgery.”
This was a mild way of putting it; M. Le Fort’s words were, “That theory, in its applications to clinical surgery, is absolutely inacceptable.” For him, the original purulent infection, though coming from the wound, was born under the influence of general and local phenomena within the patient, and not outside him. He believed that the economy had the power, under various influences, to produce purulent infection. A{271} septic poison was created, born spontaneously, which was afterwards carried to other patients by such medicines as the tools and bandages and the hands of the surgeon. But, originally, before the propagation of the contagium germ, a purulent infection was spontaneously produced and developed. And, in order to put his teaching into forcible words, M. Le Fort declared to the Académie de Médecine: “I believe in the interiority of the principle of purulent infection in certain patients; that is why I oppose the extension to surgery of the germ theory which proclaims the constant exteriority of that principle.”
Pasteur rose, and with his firm, powerful voice, exclaimed: “Before the Academy accepts the conclusion of the paper we have just heard, before the application of the germ theory to pathology is condemned, I beg that I may be allowed to make a statement of the researches I am engaged in with the collaboration of Messrs. Joubert and Chamberland.”
His impatience was so great that he formulated then and there some headings for the lecture he was preparing, propositions on septic?mia or putrid infection, on the septic vibrio itself, on the germs of that vibrio carried by wind in the shape of dust, or suspended in water, on the vitality of those germs, etc. He called attention to the mistakes which might be made if, in that new acquaintance with microbes, their morphologic aspect alone was taken account of. “The septic vibrio, for instance, varies so much in its shape, length and thickness, according to the media wherein it is cultivated, that one would think one was dealing with beings specifically distinct from each other.”
It was on April 30, 1878, that Pasteur read that celebrated lecture on the germ theory, in his own name and in that of Messrs. Joubert and Chamberland. It began by a proud exordium: “All Sciences gain by mutual support. When, subsequently to my early communications on fermentations, in 1857—1858, it was admitted that ferments, properly so called, are living beings; that germs of microscopical organisms abound on the surface of all objects in the atmosphere and in water; that the hypothesis of spontaneous generation is a chimera; that wines, beer, vinegar, blood, urine and all the liquids of the economy are preserved from their common changes when in contact with pure air—Medicine and Surgery cast their eyes towards these new lights. A French physician, M. Davaine,{272} made a first successful application of those principles to medicine in 1863.”
Pasteur himself, elected to the Académie des Sciences as a mineralogist, proved by the concatenation of his studies within the last thirty years that Science was indeed one and all embracing. Having thus called his audience’s attention to the bonds which connect one scientific subject with another, Pasteur proceeded to show the connection between his yesterday’s researches on the etiology of Charbon to those he now pursued on septic?mia. He hastily glanced back on his successful cultures of the bacillus anthracis, and on the certain, indisputable proof that the last culture acted equally with the first in producing charbon within the body of animals. He then owned to the failure, at first, of a similar method of cultivating the septic vibrio: “All our first experiments failed in spite of the variety of culture media that we used; beer-yeast water, meat broth, etc., etc....”
He then expounded, in the most masterly manner: (1) the idea which had occurred to him that this vibrio might be an exclusively ana?robic organism, and that the sterility of the liquids might proceed from the fact that the vibrio was killed by the oxygen held in a state of solution by those liquids; (2) the similarity offered by analogous facts in connection with the vibrio of butyric fermentation, which not only lives without air, but is killed by air; (3) the attempts made to cultivate the septic vibrio in a vacuum or in the presence of carbonic acid gas, and the success of both those attempts; and, finally, as the result of the foregoing, the proof obtained that the action of the air kills the septic vibriones, which are then seen to perish, under the shape of moving threads, and ultimately to disappear, as if burnt away by oxygen.
“If it is terrifying,” said Pasteur, “to think that life may be at the mercy of the multiplication of those infinitesimally small creatures, it is also consoling to hope that Science will not always remain powerless before such enemies, since it is already now able to inform us that the simple contact of air is sometimes sufficient to destroy them. But,” he continued, meeting his hearers’ possible arguments, “if oxygen destroys vibriones, how can septic?mia exist, as it does, in the constant presence of atmospheric air? How can those facts be reconciled with the germ theory? How can blood exposed to air become septic through the dusts contained in air? All is dark,{273} obscure and open to dispute when the cause of the phenomena is not known; all is light when it is grasped.”
In a septic liquid exposed to the contact of air, vibriones die and disappear; but, below the surface, in the depths of the liquid (one centimetre of septic liquid may in this case be called depths), “the vibriones are protected against the action of oxygen by their brothers, who are dying above them, and they continue for a time to multiply by division; they afterwards produce germs or spores, the filiform vibriones themselves being gradually reabsorbed. Instead of a quantity of moving threads, the length of which often extends beyond the field of the microscope, nothing is seen but a dust of isolated, shiny specks, sometimes surrounded by a sort of amorphous gangue hardly visible. Here then is the septic dust, living the latent life of germs, no longer fearing the destructive action of oxygen, and we are now prepared to understand what seemed at first so obscure: the sowing of septic dust into putrescible liquids by the surrounding atmosphere, and the permanence of putrid diseases on the surface of the earth.”
Pasteur continued from this to open a parenthesis on diseases “transmissible, contagious, infectious, of which the cause resides essentially and solely in the presence of microscopic organisms. It is the proof that, for a certain number of diseases, we must for ever abandon the ideas of spontaneous virulence, of contagious and infectious elements suddenly produced within the bodies of men or of animals and originating diseases afterwards propagated under identical shapes; all those opinions fatal to medical progress and which are engendered by the gratuitous hypotheses of the spontaneous generation of albuminoid-ferment materia, of hemiorganism, of archebiosis, and many other conceptions not founded on observation.”
Pasteur recommended the following experiment to surgeons. After cutting a fissure into a leg of mutton, by means of a bistoury, he introduced a drop of septic vibrio culture; the vibrio immediately did its work. “The meat under those conditions becomes quite gangrened, green on its surface, swollen with gases, and is easily crushed into a disgusting, sanious pulp.” And addressing the surgeons present at the meeting: “The water, the sponge, the charpie with which you wash or dress a wound, lay on its surface germs which, as you see, have an extreme facility of propagating within the tissues, and which{274} would infallibly bring about the death of the patients within a very short time if life in their limbs did not oppose the multiplication of germs. But how often, alas, is that vital resistance powerless! how often do the patient’s constitution, his weakness, his moral condition, the unhealthy dressings, oppose but an insufficient barrier to the invasion of the Infinitesimally Small with which you have covered the injured part! If I had the honour of being a surgeon, convinced as I am of the dangers caused by the germs of microbes scattered on the surface of every object, particularly in the hospitals, not only would I use absolutely clean instruments, but, after cleansing my hands with the greatest care and putting them quickly through a frame (an easy thing to do with a little practice), I would only make use of charpie, bandages, and sponges which had previously been raised to a heat of 130° C. to 150° C.; I would only employ water which had been heated to a temperature of 110° C. to 120° C. All that is easy in practice, and, in that way, I should still have to fear the germs suspended in the atmosphere surrounding the bed of the patient; but observation shows us every day that the number of those germs is almost insignificant compared to that of those which lie scattered on the surface of objects, or in the clearest ordinary water.”
He came down to the smallest details, seeing in each one an application of the rigorous principles which were to transform Surgery, Medicine and Hygiene. How many human lives have since then been saved by the dual development of that one method! The defence against microbes afforded by the substances which kill them or arrest their development, such as carbolic acid, sublimate, iodoform, salol, etc., etc., constitutes antisepsis; then the other progress, born of the first, the obstacle opposed to the arrival of the microbes and germs by complete disinfection, absolute cleanliness of the instruments and hands, of all which is to come into contact with the patient; in one word, asepsis.
It might have been prophesied at that date that Pasteur’s surprised delight at seeing his name gratefully inscribed on the great Italian establishment of sericiculture would one day be surpassed by his happiness in living to see realized some of the progress and benefits due to him, his name invoked in all operating theatres, engraved over the doors of medical and surgical wards, and a new era inaugurated.
A presentiment of the future deliverance of Humanity from{275} those redoubtable microscopic foes gave Pasteur a fever for work, a thirst for new research, and an immense hope. But once again he constrained himself, refrained from throwing himself into varied studies, and, continuing what he had begun, reverted to his studies on splenic fever.
The neighbourhood of Chartres being most afflicted, the Minister of Agriculture, anticipating the wish of the Conseil Général of the department of Eure et Loir, had entrusted Pasteur with the mission of studying the causes of so-called spontaneous charbon, that which bursts out unexpectedly in a flock, and of seeking for curative and preventive means of opposing the evil. Thirty-six years earlier, the learned veterinary surgeon, Delafond, had been sent to seek, particularly in the Beauce country, the causes of the charbon disease. Bouley, a great reader, said that there was no contrast more instructive than that which could be seen between the reasoning method followed by Delafond and the experimental method practised by Pasteur. It was in 1842 that Delafond received from M. Cunin Gridaine, then Minister of Agriculture, the mission of “going to study that malady on the spot, to seek for its causes, and to examine particularly whether those causes did not reside in the mode of culture in use in that part of the country.” Delafond arrived in the Beauce, and, having seen that the disease struck the strongest sheep, it occurred to him that it came from “an excess of blood circulating in the vessels.” He concluded from that that there might be a correlation between the rich blood of the Beauce sheep and the rich nitrogenous pasture of their food.
He therefore advised the cultivators to diminish the daily ration; and he was encouraged in his views by noting that the frequency of the disease diminished in poor, damp, or sandy soils.
Bouley, in order to show up Delafond’s efforts to make facts accord with his reasoning, added that to explain “a disease, of which the essence is general plethora, becoming contagious and expressing itself by charbon symptoms in man,” Delafond had imagined that the atmosphere of the pens, into which the animals were crowded, was laden with evil gases and putrefying emanations which produced an alteration of the blood “due at the same time to a slow asphyxia and to the introduction through the lungs of septic elements into the blood.”
It would have been but justice to recall other researches con{276}nected with Delafond’s name. In 1863, Delafond had collected some blood infected with charbon, and, at a time when such experiments had hardly been thought of, he had attempted some experiments on the development of the bacteridium, under a watch glass, at the normal blood temperature. He had seen the little rods grow into filaments, and compared them to a “very remarkable mycelium.” “I have vainly tried to see the mechanism of fructification,” added Delafond, “but I hope I still may.” Death struck down Delafond before he could continue his work.
In 1869 a scientific congress was held at Chartres; one of the questions examined being this: “What has been done to oppose splenic fever in sheep?” A veterinary surgeon enumerated the causes which contributed, according to him, to produce and augment mortality by splenic fever: bad hygienic conditions; tainted food, musty or cryptogamized; heated and vitiated air in the crowded pens, full of putrid manure; paludic miasma or effluvia; damp soil flooded by storms, etc., etc. A well-known veterinary surgeon, M. Boutet, saw no other means to preserve what remained of a stricken flock but to take it to another soil, which, in contradiction with his colleague, he thought should be chosen cool and damp. No conclusion could be drawn. The disastrous loss caused by splenic fever in the Beauce alone was terrible; it was said to have reached 20,000,000 francs in some particularly bad years. The migration of the tainted flock seemed the only remedy, but it was diffi............