Chapter 4 CONCERNING EXPERIMENTATION OTHER THAN VIVISECTION

We must, however, give to the word "Vivisection" its largest acceptation. It is not only a question of cutting nerves, of stimulating the glands, or of exciting the muscles. There are experiments of much longer duration in which there is no mutilation properly speaking, but intoxication,[7] produced by the injection of poisons and disease germs.

It is, indeed, evident that pain can be provoked in other ways than by a sharp-edged instrument, which can always be done under an?sthesia. But may inoculation be performed? May prolonged intoxication be caused? To treat the question in all its fulness, we will put the problem in the following manner.

In order to study a disease, have we the right to give that disease to an animal?

For my part, there can be no doubt on the point, and I affirm that such is our right.

As a matter of fact, and as every unbiassed person is forced to recognise, it is only by experimentation that these diseases can be studied thoroughly. Clinical observation, bearing exclusively upon man, can only give incomplete results, much poorer, though its documents are multitudinous, than the results furnished by experimentation, which can be infinitely varied at will. If we were limited to the Hippocratic method of observation, which consists in studying the symptoms and the progress of a morbid affliction, we should be reduced to poor enough resources; and if meditation on the aphorisms of Hippocrates constituted the whole extent of our medical science, medical science would be a sad vacuum. Fortunately, however, such is not the case. Marvellous progress has been realised, which allows us to entertain quite other ideas than those of the Father of Medicine on the nature of diseases, and consequently on their treatment and their prevention. Those very persons who rise up in arms against physiological experimentation would not, I imagine, desire to be handed over to the care of a Hippocratic doctor if they were ill, to a doctor who took no notice of any modern discoveries under the pretext that they were acquired by experimentation in anima vili.

If, however, we wish to discuss the problem thoroughly, it will not do to remain on indefinite ground. Let us arrive at precise facts. I will mention only three discoveries, the importance of which is considerable, and which have been established solely by experimentation.

First of all, there is antisepsis. For centuries and centuries surgeons operated without understanding why it was that death struck down so unmercifully those operated upon. In vain did surgeons display great skill; in vain did the operation succeed: the patient died. Erysipelas, lock-jaw, abscess-formation and gangrene reigned supreme. Every confinement exposed the mother to death; the slightest wounds were followed by the most serious after-effects; in certain amputations, for instance, the mortality was 70 per cent. No one dared to touch either the peritoneum or the joints, because every operation on the peritoneum or on the articulations was sure to prove fatal. But Lister and Pasteur came! These two men, simultaneously and concurrently, demonstrated that all disease following on an operation was the result of infection by parasites. By preventing the wounds from being contaminated by parasites, infection was prevented; for the wounds themselves are innocent, as long as they are not infected.

This is the astounding and simple truth which Lister and Pasteur established. And let no one pretend it is so simple that the data could have been furnished by clinical observation alone, for such an assertion would be contradicted by the facts.

Thousands and thousands of surgeons, right up to 1868, had understood nothing of infection. In order to understand this big word "infection," which sums up in itself the whole of surgery and the whole of medicine, it was necessary to inject pus into animals, gather the microbes which then developed in the blood of these animals, isolate the microbes, cultivate them, inject them afresh, and produce an experimental disease. It was in this manner only that we were able to understand the mechanism of antisepsis, and, consequently, apply it to the treatment of operations and wounds. Three or four volumes could be written on this subject alone, but all I can attempt here is a summary of the main points. I say without hesitation that as long as clinical medicine confined itself only to the observation of patients, it was able to understand nothing, to analyse nothing, to foresee nothing. It was necessary to experiment, to sacrifice a few hundred mice, rats, and rabbits, in order to demonstrate that erysipelas is an inoculable disease, that puerperal infection is of the same nature as purulent infection, that all these diseases are due to micro-organisms, and that certain substances, called antiseptics, can stop the development of these fatal germs.

It appears quite natural to-day (and it seems to simple minds, ignorant of the past and powerless to imagine the past, that these notions have been current from all eternity) to know that instruments, water, and linen heated to 120° contain no living germs. But this discovery is not so very old. It was Pasteur who, between 1863 and 1873, established it by some memorable experiments at the cost of a little disease given to rats and guinea-pigs.

PASTEUR IN HIS LABORATORY.

facing p. 44.

Now-and I appeal to the good sense of my readers-would it be better to efface the suffering of those rats, those guinea-pigs, those rabbits, and return to the olden times when the mortality in lying-in hospitals was often 40 per cent. (it is to-day, 0.02 per cent.!)? Must we condemn Lister and Pasteur as great criminals because they dared to inoculate microbes into a few rabbits and bring about in those unfortunate animals-they would have died a long time ago even without that-experimental ailments in order to ward off malignant diseases from thousands and thousands of human beings?

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The second discovery which I shall mention is that of the infectiousness of tuberculosis. Thousands and thousands of doctors had had tuberculous patients under their care. Three thousand years ago, Hippocrates described tuberculosis with as much precision as could be done to-day. Illustrious physicians in every land had tried to analyse the nature of this terrible disease and to unravel its cause; nevertheless, they were unable, from clinical observation alone, to prove what is to-day quite commonplace knowledge, viz., that tuberculosis is infectious. In 1864, a French doctor, Villemin, conceived the simple and ingenious idea of inoculating rabbits with the tuberculous matter found in the lungs of consumptive patients. These rabbits became tuberculous; they died in a few weeks with tuberculous granulations in lungs and liver. It was thus demonstrated that tuberculosis was infectious. Later on, in 1878, Koch discovered that the active agent of this infection is a special microbe. But, however important may be the discovery of the microbe of tuberculosis (the tubercle-bacillus of Koch), the essential dominating fact is that tuberculosis is infectious.

As soon as this great fact became known, a profound revolution occurred in social hygiene, in the treatment and in the prevention of this terrible evil. We know now the consumptive man carries in his lungs and sputum the germ capable of developing the same evil in others; consequently we know how to preserve ourselves against tuberculosis. We must purify or destroy the habitations wherein consumptives have lived, burn or carbolise all the sputum, make spitting in public places a punishable offence, take sanitary measures against unhealthy meat, defend our children against contaminated milk-in a word, we are armed against a disease, the sole and unique cause of which, as experimentation alone has taught us, is infection.

Formerly it was believed that diseases were due to a sort of divine anger, or, what amounts pretty much to the same thing, to certain imperceptible epidemic exhalations stretching over whole populations, or attacking isolated individuals, striking like an exterminating angel, as his fancy chose, such or such an unhappy victim. A sort of will or caprice, governed only by chance, was exercised in relation to this disease, and man was powerless, because he was unarmed against chance. He did not even think of it. He resigned himself to being ill, and waited for the disease, without doing anything to fight against it, benumbed under a kind of Oriental fatalism. The doctor shook his head, bore testimony to the evil, and confined himself to prescribing inefficacious treatments which were only, according to a celebrated saying, a long meditation on death.

But the times have changed; there is no longer any fatality in tuberculosis; there is imprudence, there is error, there is vice, and, specially, social vice. We may almost say that, if there are still consumptives in our midst, it is because of our defective social institutions. We leave innumerable populations steeped in misery, seven or eight individuals living in the same infected hovel. In the slums of our large cities, swarms of infants are to be found morally and materially perverted by misery. Therefore, if consumption still exists, it is our own fault; it is no longer as it was in olden times, when we knew not, because now we know. The plague can be battled with; and if it still has so much power left, it is because we have not the courage to apply to public and individual hygiene the treatment science has definitely shown us should be applied. To foresee is to know; and now that we know, we must not forget that it is to experimenters, and to experimenters alone, that we are indebted for this great benefit.

Moreover, however imperfect our defence against tuberculosis may still be, it is by no means nil; great progress has been made; the mortality has decreased in a considerable proportion. During the last twenty-five years, it has decreased by about 25 per cent., and notably in England, where the laws of public hygiene, energetically upheld by the good sense of the people, are strictly applied, the mortality has diminished by 50 per cent. This is only a beginning, and the near future will bring about the complete extermination of the disease.

Now, honestly, I ask if the rabbits which Villemin sacrificed weigh more in the scales of universal progress, and even in public morality, than the three millions of individuals who, by progress in hygiene, have been preserved from an early and painful death. I estimate at a high price the life and the sufferings of fifty rabbits, but, at the risk of appearing a barbarian, I prefer, to these fifty rabbits, the three millions of young people who have been saved by Villemin's discovery, and the millions which it will still save.

All the more so, inasmuch as experimental studies on tuberculosis have not only preserved men; they have also preserved animals. Thanks to Koch, there is now a very simple way of recognising if an animal is or is not tuberculous. Koch was able to extract from tubercle bacilli, a substance which he has called tuberculin. At first he thought tuberculin cured the disease; but this was an error. Subsequent experiments showed that tuberculin exercised quite a different action to that of healing. It has the property, when injected in small doses into a tuberculous animal, of provoking an intense fever, whilst it produces no reaction whatsoever in a normal animal. If, therefore, tuberculin is injected into every animal in the cattle shed, we can feel sure-and this is impossible otherwise-that such or such animals are tuberculous or healthy. All cows that show a rise in temperature after an injection of tuberculin are tuberculous; the others, on the contrary, are in good health.

Thus the sanitary inspection of stables and cattle-sheds can be carried out thoroughly; and we are now able to protect not only men but also animals from the disease of tuberculosis.

Such results could only have been obtained at the cost of many and methodical experiments. Whatever may be the genius of anti-vivisectionists, they would never have been able to imagine anything similar had they been left to their own intellectual powers. It is not in the study that we are able to discover this long series of unforeseen, extraordinary, almost miraculous facts which laboratory experimentation has been able to find out. Man, said Pascal, tires of conceiving sooner than Nature tires of providing; and experimentation is man's method of interrogating Nature.

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The third discovery which I shall take as an example demonstrating the value of experimentation, is the history of Serotherapy. And I may be permitted to dwell somewhat on this subject as I had the good fortune, in 1888, of making the decisive experiment which was the beginning of serotherapy.

Whilst inoculating some rabbits and dogs with a microbe taken from pus (Staphylococcus pyosepticus), I developed a certain disease both in the rabbits and in the dogs. But the dogs did not die, whilst all the rabbits died from the results of the inoculation. I thought then that, the cause of that resistance being due to the difference of blood, I might be able to make the rabbit refractory to the infection by injecting it with the blood of a dog in normal health. The experiment succeeded. The rabbits which had received the blood of the dog, when they were afterwards infected with the staphylococcus, became very ill but did not die. Later on, I took, not the blood of a dog in normal health, but the blood of a dog that had received the infection of the staphylococcus and had recovered from that infection, and I injected this blood into the rabbits. Now the rabbits that received the blood of the infected, healed dog had acquired complete immunity to this form of microbe infection: the principle of serotherapy was discovered (5th Nov. 1888).

"L'ENFANT."

In Musée du Luxembourg, Paris.

facing p. 53.

Since then, serotherapy has been applied, by Behring in Germany and by Roux in France, to diphtheria (1892). These two savants showed that the blood of animals, and especially of horses, that had been infected with diphtheria and cured, could, when injected into patients attacked by diphtheria, diminish, in an extraordinary proportion, the duration and intensity of the disease. There is no other treatment for diphtheria to-day. A doctor is guilty, and even criminal, if he does not use it, for the therapeutic results of this treatment are marvellous.

I do not speak of clinical observation only. All those who have seen the effects of one of these injections of serum on children down with diphtheria are veritably stupefied at the resurrection which they witness only a few minutes after the injection. The unfortunate child with his purple face and convulsed limbs, scarcely breathing, comes back to fresh life as soon as he has received the beneficent injection of serum. The facts are so decisively clear that even if we have only seen them once we can never again forget them. But I shall simply call the attention of my readers to the following statistics, the result of more than 500,000 observations made in England, in the United States, in France, in Russia, in Germany, in Italy, in Austria, in fact everywhere: the death-rate in diphtheria before 1892 (for the serotherapic method took four years to become known and practised) was 45 per cent. After 1892, this death-rate fell to 12 per cent.[8] Consequently, out of every hundred patients suffering from diphtheria, thirty are saved by the serotherapic treatment.

Let us stop for a moment to consider these figures, which seem mere abstractions to those who have not reflected. At the present time, about 300,000 children per annum in France are attacked by diphtheria; that makes 4,500,000 from 1892 to 1907. The proportion of 30 per cent. is therefore 1,350,000. The number of children who have been saved in France alone by serotherapy in fifteen years is therefore 1,350,000. Let us put it in round numbers at one million only; this would be sufficient to justify the death of the twenty-five dogs and the one hundred rabbits which I sacrificed, and of the two hundred horses which Behring and Roux used for the preparation of the anti-diphtheria serum. A million families in mourning, a million hopes mowed down in the bud! Only fanatics would dare to say this weighs for nought in the balance.

Moreover-and why should I not say it aloud?-this so-called humanity of anti-vivisectionists seems to me the antithesis of humanity. To satisfy a conception which they have forged out of a certain hazy ideal, they make quick shrift of human life and suffering. A hundred weeping mothers, a hundred unfortunate children with gaping throats, suffocating, gasping, the death-rattle at hand-that is what these sensitive souls declare is nothing beside one rabbit which has had to receive a little blood of a dog into its abdomen! These philanthropists are creatures of a fixed idea! Let humanity suffer, weep and die! What does that matter, provided that their fixed idea, driven right up to the hilt of delirium, triumphs! After all, if they persist in believing that the faint and uncertain suffering of a sick rabbit is not worth the certain and excruciating suffering of a thousand human creatures, I can say but one thing: I pity them from the very bottom of my heart.

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These examples-antisepsis, tuberculosis, and serotherapy-will suffice perhaps to justify experimental pathology. There is now another experimental science which I am going to try to justify also. This is Therapeutics.

We are only able to learn the action of medicaments by studying the action of poisons, for all medicaments in strong doses are poisonous. Now, to understand a poison thoroughly, we must experiment with it on the animal. Simpson administered chloroform to men only after Flourens had determined its an?sthesic properties on animals. Liebreich, after he discovered chloral, studied its physiological properties on animals, and only after long and learned studies was he able to give it a place in human therapeutics. At the present day, chloral is one of the most extensively used medicines, one which has relieved innumerable patients. When I carried out my research on chloralose, before studying its effects on myself, I began by giving it to cats and fowls. I was ignorant of the degree of toxic power of this new, still unknown substance, and, at the risk of appearing very pusillanimous, I did not wish to begin on myself; I preferred trying it on a fowl. Not that I estimate my life very highly, but after all, however low an estimate I may place on my own life, I think it is worth more than that of a fowl. Many other medicines have been thus experimented with on animals before it was possible to ascertain their effects on man. Kocher discovered cocaine, Knorr antipyrine; and these two admirable medicines did not find their way into therapeutics until their mode of action and their toxic power had been ascertained on animals.

In a word, the whole of present-day therapeutics has for foundation, not only ancient clinical observation, which it would be supremely foolish to disdain, but also the experiments of modern times, which it would be equally foolish to proscribe.

Perhaps certain people imagine that there are no therapeutics, and that we can replace by auto-suggestion, prayer, or hypnotisation, everything which doctors generally use to cure or allay disease. It is difficult to reply to such objections, because those who make them have never opened a work of science nor seen a patient. They see things as they wish to see them. They imagine that the exterior world is constructed according to their interior vision, and they do not deign to come into contact with reality. They believe that enthusiasm can supply the place of instruction, and that a certain doubtful generosity can replace profound and patient study. They maintain perhaps that chloral does not make one sleep, that salicylate of soda does not alleviate rheumatic pains, that bromide of potassium does not check attacks of epilepsy. Perhaps they will even continue to say so for a long time to come. Let them talk; progress will be made without them.

Les chiens aboient et la caravane passe.

FOOTNOTES:

[7] See footnote, p. 17.

[8] These statistics can be found in all technical works; and I refer those who may be curious to study them in detail to the special memoirs and excellent treatises on pathology which have been published in England, France, and Germany.

See also appendix.

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