1877--1879
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 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 Grâce, 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 cow’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 household 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 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.
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 septicæmia (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 septicæmia,
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 cultures caused septicæmia in an animal. But, while the bacillus
anthracis is aërobic, the septic vibrio, being anaërobic, 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.
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 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 septicæmia. 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 mixture 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, 1878: “Dear colleague and friend, _microbe_ and _microbia_ are very
good words. To designate the animalculæe 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 μιχρόβιος and μαχρόβιος
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
βίος, life, βιοῦν, to live, βιούς, living, the root of which may very
well figure under the form of _bi_, _bia_ with the sense _living_, in
_aërobia_, _anaërobia_ 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 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 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 bacteridia 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 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 septicæmia 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, 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 septicæmia. 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 anaërobic
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 septicæmia 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, 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 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 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 connected
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 difficult in
practice and offered danger to other flocks, as carcases of dead sheep
were wont to mark the road that had been followed.
Pasteur, starting from the fact that the charbon disease is produced by
the bacteridium, proposed to prove that, in a department like that of
Eure et Loir, the disease maintained itself by itself. When an animal
dies of splenic fever in a field, it is frequently buried in the very
spot where it fell; thus a focus of contagion is created, due to the
anthrax spores mixed with the earth where other flocks are brought to
graze. Those germs, thought Pasteur, are probably like the germs of the
flachery vibrio, which survive from one year to another and transmit the
disease. He proposed to study the disease on the spot.
It almost always happened that, when he was most anxious to give himself
up entirely to the study of a problem, some new discussion was started
to hinder him. He had certainly thought that the experimental power of
giving anthrax to hens had been fully demonstrated, and that that
question was dead, as dead as the inoculated and immersed hen.
Colin, however, returned to the subject, and at an Academy meeting of
July 9 said somewhat insolently, “I wish we could have seen the
bacteridia of that dead hen which M. Pasteur showed us without taking it
out of its cage, and which he took away intact instead of making us
witness the necropsy and microscopical examination.” “I will take no
notice,” said Pasteur at the following meeting, “of the malevolent
insinuations contained in that sentence, and only consider M. Colin’s
desire to hold in his hands the body of a hen dead of anthrax, full of
bacteridia. I will, therefore, ask M. Colin if he will accept such a hen
under the following condition: the necropsy and microscopic examination
shall be made by himself, in my presence, and in that of one of our
colleagues of this Academy, designated by himself or by this Academy,
and an official report shall be drawn up and signed by the persons
present. So shall it be well and duly stated that M. Colin’s
conclusions, in his paper of May 14, are null and void. The Academy will
understand my insistence in rejecting M. Colin’s superficial
contradictions.
“I say it here with no sham modesty: I have always considered that my
only right to a seat in this place is that given me by your great
kindness, for I have no medical or veterinary knowledge. I therefore
consider that I must be more scrupulously exact than any one else in the
presentations which I have the honour to make to you; I should promptly
lose all credit if I brought you erroneous or merely doubtful facts. If
ever I am mistaken, a thing which may happen to the most scrupulous, it
is because my good faith has been greatly surprised.
“On the other hand, I have come amongst you with a programme to follow
which demands accuracy at every step. I can tell you my programme in two
words: I have sought for twenty years, and I am still seeking,
spontaneous generation properly so called.
“If God permit, I shall seek for twenty years and more the spontaneous
generation of transmissible diseases.
“In these difficult researches, whilst sternly deprecating frivolous
contradiction, I only feel esteem and gratitude towards those who may
warn me if I should be in error.”
The Academy decided that the necropsy and microscopic examination of the
dead hen which Pasteur was to bring to Colin should take place in the
presence of a Commission composed of Pasteur, Colin, Davaine, Bouley,
and Vulpian. This Commission met on the following Saturday, July 20, in
the Council Chamber of the Academy of Medicine. M. Armand Moreau, a
member of the Academy, joined the five members present, partly out of
curiosity, and partly because he had special reasons for wishing to
speak to Pasteur after the meeting.
Three hens were lying on the table, all of them dead. The first one had
been inoculated under the thorax with five drops of yeast water slightly
alkalized, which had been given as a nutritive medium to some bacteridia
anthracis; the hen had been placed in a bath at 25° C., and had died
within twenty-two hours. The second one, inoculated with ten drops of a
culture liquid, had been placed in a warmer bath, 30° C., and had died
in thirty-six hours. The third hen, also inoculated and immersed, had
died in forty-six hours.
Besides those three dead hens, there was a living one which had been
inoculated in the same way as the first hen. This one had remained for
forty-three hours with one-third of its body immersed in a barrel of
water. When it was seen in the laboratory that its temperature had gone
down to 36° C., that it was incapable of eating and seemed very ill, it
was taken out of the tub that very Saturday morning, and warmed in a
stove at 42° C. It was now getting better, though still weak, and gave
signs of an excellent appetite before leaving the Academy council
chamber.
The third hen, which had been inoculated with ten drops, was dissected
then and there. Bouley, after noting a serous infiltration at the
inoculation focus, showed to the judges sitting in this room, thus
suddenly turned into a testing laboratory, numerous bacteridia scattered
throughout every part of the hen.
“After those ascertained results,” wrote Bouley, who drew up the report,
“M. Colin declared that it was useless to proceed to the necropsy of the
two other hens, that which had just been made leaving no doubt of the
presence of bacilli anthracis in the blood of a hen inoculated with
charbon and then placed under the conditions designated by M. Pasteur as
making inoculation efficacious.
“The hen No. 2 has been given up to M. Colin to be used for any
examination or experiment which he might like to try at Alfort.
“Signed: G. Colin, H. Bouley, C. Davaine, L. Pasteur, A. Vulpian.”
“This is a precious autograph, headed as it is by M. Colin’s signature!”
gaily said Bouley. But Pasteur, pleased as he was with this conclusion,
which put an end to all discussion on that particular point, was already
turning his thoughts into another channel. The Academician who had
joined the members of the Commission was showing him a number of the
_Revue Scientifique_ which had appeared that morning, and which
contained an article of much interest to Pasteur.
In October, 1877, Claude Bernard, staying for the last time at St.
Julien, near Villefranche, had begun some experiments on fermentations.
He had continued them on his return to Paris, alone, in the study which
was above his laboratory at the Collège de France.
When Paul Bert, his favourite pupil, M. d’Arsonval, his curator, M.
Dastre, a former pupil, and M. Armand Moreau, his friend, came to see
him, he said to them in short, enigmatical sentences, with no comment or
experimental demonstration, that he had done some good work during the
vacation. “Pasteur will have to look out.... Pasteur has only seen one
side of the question.... I make alcohol without cells.... There is no
life without air....”
Bernard’s and Pasteur’s seats at the Academy of Sciences were next to
each other, and they usually enjoyed interchanging ideas. Claude Bernard
had come to the November and December sittings, but, with a reticence to
which he had not accustomed Pasteur, he had made no allusion to his
October experiments. In January, 1878, he became seriously ill; in his
conversations with M. d’Arsonval, who was affectionately nursing him,
Claude Bernard talked of his next lecture at the Museum, and said that
he would discuss his ideas with Pasteur before handling the subject of
fermentations. At the end of January M. d’Arsonval alluded to these
incomplete revelations. “It is all in my head,” said Claude Bernard,
“but I am too tired to explain it to you.” He made the same weary answer
two or three days before his death. When he succumbed, on February 10,
1878, Paul Bert, M. d’Arsonval and M. Dastre thought it their duty to
ascertain whether their master had left any notes relative to the work
which embodied his last thoughts. M. d’Arsonval, after a few days’
search, discovered some notes, carefully hidden in a cabinet in Claude
Bernard’s bedroom; they were all dated from the 1st to the 20th of
October, 1877; of November and December there was no record. Had he then
not continued his experiments during that period? Paul Bert thought that
these notes did not represent a work, not even a sketch, but a sort of
programme. “It was all condensed into a series of masterly conclusions,”
said Paul Bert, “which evidenced certitude, but there were no means of
discussing through which channel that certitude had come to his prudent
and powerful mind.” What should be done with those notes? Claude
Bernard’s three followers decided to publish them. “We must,” said Paul
Bert, “while telling the conditions under which the manuscript was
found, give it its character of incomplete notes, of confidences made to
itself by a great mind seeking its way, and marking its road
indiscriminately with facts and with hypotheses in order to arrive at
that feeling of certainty which, in the mind of a man of genius, often
precedes proof.” M. Berthelot, to whom the manuscript was brought,
presented these notes to the readers of the _Revue Scientifique_. He
pointed to their character, too abbreviated to conclude with a rigorous
demonstration, but he explained that several friends and pupils of
Claude Bernard had “thought that there would be some interest for
Science in preserving the trace of the last subjects of thought, however
incomplete, of that great mind.”
Pasteur, after the experiment at the Académie de Médecine, hurried back
to his laboratory and read with avidity those last notes of Claude
Bernard. Were they a precious find, explaining the secrets Claude
Bernard had hinted at? “Should I,” said Pasteur, “have to defend my
work, this time against that colleague and friend for whom I professed
deep admiration, or should I come across unexpected revelations,
weakening and discrediting the results I thought I had definitely
established?”
His reading reassured him on that point, but saddened him on the other
hand. Since Claude Bernard had neither desired nor even authorized the
publication of those notes, why, said Pasteur, were they not accompanied
by an experimental commentary? Thus Claude Bernard would have been
credited with what was good in his MSS., and he would not have been held
responsible for what was incomplete or defective.
“As for me, personally,” wrote Pasteur in the first pages of his
_Critical Examination of a Posthumous Work of Claude Bernard on
Fermentation_, “I found myself cruelly puzzled; had I the right to
consider Claude Bernard’s MS. as the expression of his thought, and was
I free to criticize it thoroughly?” The table of contents and headings
of chapters in Claude Bernard’s incomplete MS. condemned Pasteur’s work
on alcoholic fermentation. The non-existence of life without air; the
ferment not originated by exterior germs; alcohol formed by a soluble
ferment outside life ... such were Claude Bernard’s conclusions. “If
Claude Bernard was convinced,” thought Pasteur, “that he held the key to
the masterly conclusions with which he ended his manuscript, what could
have been his motive in withholding it from me? I looked back upon the
many marks of kindly affection which he had given me since I entered on
a scientific career, and I came to the conclusion that the notes left by
Bernard were but a programme of studies, that he had tackled the
subject, and that, following in this a method habitual to him, he had,
the better to discover the truth, formed the intention of trying
experiments which might contradict my opinions and results.”
Pasteur, much perplexed, resolved to put the case before his colleagues,
and did so two days later. He spoke of Bernard’s silence, his abstention
from any allusion at their weekly meetings. “It seems to me almost
impossible,” he said, “and I wonder that those who are publishing these
notes have not perceived that it is a very delicate thing to take upon
oneself, with no authorization from the author, the making public of
private notebooks! Which of us would care to think it might be done to
him!... Bernard must have put before himself that leading idea, that I
was in the wrong on every point, and taken that method of preparing the
subject he intended to study.” Such was also the opinion of those who
remembered that Claude Bernard’s advice invariably was that every theory
should be doubted at first and only trusted when found capable of
resisting objections and attacks.
“If then, in the intimacy of conversation with his friends and the yet
more intimate secret of notes put down on paper and carefully put away,
Claude Bernard develops a plan of research with a view to judging of a
theory--if he imagines experiments--he is resolved not to speak about it
until those experiments have been clearly checked; we should therefore
not take from his notes the most expressly formulated propositions
without reminding ourselves that all that was but a project, and that he
meant to go once again through the experiments he had already made.”
Pasteur declared himself ready to answer any one who would defend those
experiments which he looked upon as doubtful, erroneous, or wrongly
interpreted. “In the opposite case,” he said, “out of respect for Claude
Bernard’s memory, I will repeat his experiments before discussing them.”
Some Academicians discoursed on these notes as on simple suggestions and
advised Pasteur to continue his studies without allowing himself to be
delayed by mere control experiments. Others considered these notes as
the expression of Claude Bernard’s thought. “That opinion,” said
Pasteur--man of sentiment as he was--“that opinion, however, does not
explain the enigma of his silence towards me. But why should I look for
that explanation elsewhere than in my intimate knowledge of his fine
character? Was not his silence a new proof of his kindness, and one of
the effects of our mutual esteem? Since he thought that he held in his
hands a proof that the interpretation I had given to my experiments was
fallacious, did he not simply wish to wait to inform me of it until the
time when he thought himself ready for a definite statement? I prefer to
attribute high motives to my friend’s actions, and, in my opinion, the
surprise caused in me by his reserve towards the one colleague whom his
work most interested should give way in my heart to feelings of pious
gratitude. However, Bernard would have been the first to remind me that
scientific truth soars above the proprieties of friendship, and that my
duty lies in discussing views and opinions in my turn with full
liberty.”
Pasteur having made this communication to the Academy on July 22,
hastily ordered three glass houses, which he intended to take with him
into the Jura, “where I possess,” he told his colleagues, “a vineyard
occupying some thirty or forty square yards.”
Two observations expounded in a chapter of his _Studies on Beer_ tend to
establish that yeast can only appear about the time when grapes ripen,
and that it disappears in the winter only to show itself again at the
end of the summer. Therefore “germs of yeast do not yet exist on green
grapes.” “We are,” he added, “at an epoch in the year when, by reason
of the lateness of vegetation due to a cold and rainy season, grapes
are still in the green stage in the vineyards of Arbois. If I choose
this moment to enclose some vines in almost hermetically closed glass
houses, I shall have in October during the vintage some vines bearing
ripe grapes without the exterior germs of wine yeast. Those grapes,
crushed with precautions which will not allow of the introduction of
yeast germs, will neither ferment nor produce wine. I shall give myself
the pleasure of bringing some back to Paris, to present them to the
Academy and to offer a few bunches to those of our colleagues who are
still able to believe in the spontaneous generation of yeast.”
In the midst of the agitation caused by that posthumous work some said,
or only insinuated, that if Pasteur was announcing new researches on the
subject, it was because he felt that his work was threatened.
“I will not accept such an interpretation of my conduct,” he wrote to J.
B. Dumas on August 4, 1878, at the very time when he was starting for
the Jura; “I have clearly explained this in my notice of July 22, when I
said I would make new experiments solely from respect to Bernard’s
memory.”
As soon as Pasteur’s glass houses arrived, they were put up in the
little vineyard he possessed, two kilometres from Arbois. While they
were being put together, he examined whether the yeast germs were really
absent from the bunches of green grapes; he had the satisfaction of
seeing that it was so, and that the particular branches which were about
to be placed under glass did not bear a trace of yeast germs. Still,
fearing that the closing of the glass might be insufficient and that
there might thus be a danger of germs, he took the precaution, “while
leaving some bunches free, of wrapping a few on each plant with cotton
wool previously heated to 150° C.”
He then returned to Paris and his studies on anthrax, whilst patiently
waiting for the ripening of his grapes.
Besides M. Chamberland, Pasteur had enrolled M. Roux, the young man who
was so desirous of taking part in the work at the laboratory. He and M.
Chamberland were to settle down at Chartres in the middle of the summer.
A recent student of the Alfort Veterinary School, M. Vinsot, joined them
at his own request. M. Roux has told of those days in a paper on
_Pasteur’s Medical Work_:
“Our guide was M. Boutet, who had unrivalled knowledge of the splenic
fever country, and we sometimes met M. Toussaint, who was studying the
same subject as we were. We have kept a pleasant memory of that campaign
against charbon in the Chartres neighbourhood. Early in the morning, we
would visit the sheepfolds scattered on that wide plateau of the Beauce,
dazzling with the splendour of the August sunshine; then necropsies took
place in M. Rabourdin’s knacker’s yard or in the farmyards. In the
afternoon, we edited our experiment notebooks, wrote to Pasteur, and
arranged for new experiments. The day was well filled, and how
interesting and salutary was that bacteriology practised in the open
air!
“On the days when Pasteur came to Chartres, we did not linger over our
lunch at the Hôtel de France; we drove off to St. Germain, where M.
Maunoury had kindly put his farm and flocks at our disposal. During the
drive we talked of the week’s work and of what remained to be done.
“As soon as Pasteur left the carriage he hurried to the folds. Standing
motionless by the gate, he would gaze at the lots which were being
experimented upon, with a careful attention which nothing escaped; he
would spend hours watching one sheep which seemed to him to be
sickening. We had to remind him of the time and to point out to him that
the towers of Chartres Cathedral were beginning to disappear in the
falling darkness before we could prevail upon him to come away. He
questioned farmers and their servants, giving much credit to the
opinions of shepherds, who on account of their solitary life, give their
whole attention to their flocks and often become sagacious observers.”
When again at Arbois, on September 17, Pasteur began to write to the
Minister of Agriculture a note on the practical ideas suggested by this
first campaign. A few sheep, bought near Chartres and gathered in a
fold, had received, amongst the armfuls of forage offered them, a few
anthrax spores. Nothing had been easier than to bring these from the
laboratory, in a liquid culture of bacteria, and to scatter them on the
field where the little flock grazed. The first meals did not give good
scientific results, death was not easily provoked. But when the
experimental menu was completed by prickly plants, likely to wound the
sheep on their tongue or in their pharynx, such, for instance, as
thistles or ears of barley, the mortality began. It was perhaps not as
considerable as might have been wished for demonstration purposes, but
nevertheless it was sufficient to explain how charbon could declare
itself, for necropsy showed the characteristic lesions of the so-called
spontaneous splenic fever. It was also to be concluded therefrom that
the evil begins in the mouth, or at the back of the throat, supervening
on meals of infected food, alone or mixed with prickly plants likely to
cause abrasion.
It was therefore necessary, in a department like that of Eure et Loir,
which must be full of anthrax germs,--particularly on the surface of the
graves containing carcases of animals which had fallen victims to the
disease,--that sheep farmers should keep from the food of their animals
plants such as thistles, ears of barley, and sharp pieces of straw; for
the least scratch, usually harmless to sheep, became dangerous through
the possible introduction of the germs of the disease.
“It would also be necessary” wrote Pasteur, “to avoid all probable
diffusion of charbon germs through the carcases of animals dying of that
disease, for it is likely that the department of Eure et Loir contains
those germs in greater quantities than the other departments; splenic
fever having long been established there, it always goes on, dead
animals not being disposed of so as to destroy all germs of ulterior
contagion.”
After finishing this report, Pasteur went to his little vineyard on the
Besançon road, where he met with a disappointment; his precious grapes
had not ripened, all the strength of the plant seemed to have gone to
the wood and leaves. But the grapes had their turn at the end of
September and in October, those bunches that were swathed in cotton wool
as well as those which had remained free under the glass; there was a
great difference of colour between them, the former being very pale.
Pasteur placed grapes from the two series in distinct tubes. On October
10, he compared the grapes of the glass houses, free or swathed, with
the neighbouring open-air grapes. “The result was beyond my
expectations; the tubes of open-air grapes fermented with grape yeast
after a thirty-six or forty-eight hours’ sojourn in a stove from 25° C.
to 30° C.; not one, on the contrary, of the numerous tubes of grapes
swathed in cotton wool entered into alcoholic fermentation, neither did
any of the tubes containing grapes ripened free under glass. It was the
experiment described in my _Studies on Beer_. On the following days I
repeated these experiments with the same results.” He went on to
another experiment. He cut some of the swathed bunches and hung them to
the vines grown in the open air, thinking that those bunches--exactly
similar to those which he had found incapable of fermentation--would
thus get covered with the germs of alcoholic ferments, as did the
bunches grown in the open air and their wood. After that, the bunches
taken from under the glass and submitted to the usual régime would
ferment under the influence of the germs which they would receive as
well as the others; this was exactly what happened.
The difficulty now was to bring to the Académie des Sciences these
branches bearing swathed bunches of grapes; in order to avoid the least
contact to the grapes, these vine plants, as precious as the rarest
orchids, had to be held upright all the way from Arbois to Paris.
Pasteur came back to Paris in a coupé carriage on the express train,
accompanied by his wife and daughter, who took it in turns to carry the
vines. At last, they arrived safely at the Ecole Normale, and from the
Ecole Normale to the Institute, and Pasteur had the pleasure of bringing
his grapes to his colleagues as he had brought his hens. “If you crush
them while in contact with pure air,” he said, “I defy you to see them
ferment.” A long discussion then ensued with M. Berthelot, which was
prolonged until February, 1879.
“It is a characteristic of exalted minds,” wrote M. Roux, “to put
passion into ideas.... For Pasteur, the alcoholic fermentation was
correlative with the life of the ferment; for Bernard and M. Berthelot,
it was a chemical action like any other, and could be accomplished
without the participation of living cells.” “In alcoholic fermentation,”
said M. Berthelot, “a soluble alcoholic ferment may be produced, which
perhaps consumes itself as its production goes on.”
M. Roux had seen Pasteur try to “extract the soluble alcoholic ferment
from yeast cells by crushing them in a mortar, by freezing them until
they burst, or by putting them into concentrated saline solutions, in
order to force by osmose the succus to leave its envelope.” Pasteur
confessed that his efforts were vain. In a communication to the Académie
des Sciences on December 30, 1878, he said--
“It ever is an enigma to me that it should be believed that the
discovery of soluble ferments in fermentations properly so called, or of
the formation of alcohol by means of sugar, independently of cells
would hamper me. It is true--I own it without hesitation, and I am ready
to explain myself more lengthily if desired--that at present I neither
see the necessity for the existence of those ferments, nor the
usefulness of their action in this order of fermentations. Why should
actions of _diastase_, which are but phenomena of hydration, be confused
with those of organized ferments, or vice versâ? But I do not see that
the presence of those soluble substances, if it were ascertained, could
change in any way the conclusions drawn from my labours, and even less
so if alcohol were formed by electrolysis.
“They agree with me who admit:
“Firstly. That fermentations, properly so called, offer as an essential
condition the presence of microscopic organisms.
“Secondly. That those organisms have not a spontaneous origin.
“Thirdly. That the life of every organism which can exist away from free
oxygen is suddenly concomitant with acts of fermentation; and that it is
so with every cell which continues to produce chemical action without
the contact of oxygen.”
When Pasteur related this discussion, and formed of it an appendix to
his book, _Critical Examination of a Posthumous Work of Claude Bernard
on Fermentations_, his painful feelings in opposing a friend who was no
more were so clearly evidenced that Sainte Claire Deville wrote to him
(June 9, 1879): “My dear Pasteur, I read a few passages of your new book
yesterday to a small party of professors and _savants_. We all were much
moved by the expressions with which you praise our dear Bernard, and by
your feelings of friendship and pure fraternity.”
Sainte Claire Deville often spoke of his admiration for Pasteur’s
precision of thought, his forcible speech, the clearness of his
writings. As for J. B. Dumas, he called the attention of his colleagues
at the Académie Française to certain pages of that _Critical
Examination_. Though unaccustomed to those particular subjects, they
could not but be struck by the sagacity and ingenuity of Pasteur’s
researches, and by the eloquence inspired by his genius. A propos of
those ferment germs, which turn grape juice into wine, and from which he
had preserved his swathed bunches, Pasteur wrote--
“What meditations are induced by those results! It is impossible not to
observe that, the further we penetrate into the experimental study of
germs, the more we perceive sudden lights and clear ideas on the
knowledge of the causes of contagious diseases! Is it not worthy of
attention that, in that Arbois vineyard (and it would be true of the
million _hectares_ of vineyards of all the countries in the world),
there should not have been, at the time when I made the aforesaid
experiments, one single particle of earth which would not have been
capable of provoking fermentation by a grape yeast, and that, on the
other hand, the earth of the glass houses I have mentioned should have
been powerless to fulfil that office? And why? Because, at a given
moment, I covered that earth with some glass. The death, if I may so
express it, of a bunch of grapes thrown at that time on any vineyard,
would infallibly have occurred through the _saccharomyces_ parasites of
which I speak; that kind of death would have been impossible, on the
contrary, on the little space enclosed by my glass houses. Those few
cubic yards of air, those few square yards of soil, were there, in the
midst of a universal possible contagion, and they were safe from it.”
And suddenly looking beyond those questions of yeast and vintage,
towards the germs of disease and of death: “Is it not permissible to
believe, by analogy, that a day will come when easily applied preventive
measures will arrest those scourges which suddenly desolate and terrify
populations; such as the fearful disease (yellow fever) which has
recently invaded Senegal and the valley of the Mississippi, or that
other (bubonic plague), yet more terrible perhaps, which has ravaged the
banks of the Volga.”
Pasteur, with his quick answers, his tenacious refutations, was looked
upon as a great fighter by his colleagues at the Academy, but in the
laboratory, while seeking Claude Bernard’s soluble ferment, he tackled
subjects from which he drew conclusions which were amazing to
physicians.
A worker in the laboratory had had a series of furuncles. Pasteur, whose
proverb was “Seek the microbe,” asked himself whether the pus of
furuncles might not have an organism, which, carried to and fro,--for it
may be said that a furuncle never comes alone--would explain the centre
of inflammation and the recurrence of the furuncles. After
abstracting--with the usual purity precautions--some pus from three
successive furuncles, he found in some sterilized broth a microbe,
formed of little rounded specks which clustered to the sides of the
culture vessel. The same was observed on a man whom Dr. Maurice Raynaud,
interested in those researches on furuncles, had sent to the laboratory,
and afterwards on a female patient of the Lariboisière Hospital, whose
back was covered with furuncles. Later on, Pasteur, taken by Dr.
Lannelongue to the Trousseau Hospital, where a little girl was about to
be operated on for that disease of the bones and marrow called
_osteomyelitis_, gathered a few drops of pus from the inside and the
outside of the bone, and again found clusters of microbes. Sown into a
culture liquid, this microbe seemed so identical with the furuncle
organism that “it might be affirmed at first sight,” said Pasteur, “that
osteomyelitis is the furuncle of bones.”
The hospital now took as much place in Pasteur’s life as the laboratory.
“Chamberland and I assisted him in those studies,” writes M. Roux. “It
was to the Hôpital Cochin or to the Maternité that we went most
frequently, taking our culture tubes and sterilized pipets into the
wards or operating theatres. No one knows what feelings of repulsion
Pasteur had to overcome before visiting patients and witnessing
post-mortem examinations. His sensibility was extreme, and he suffered
morally and physically from the pains of others; the cut of the bistoury
opening an abscess made him wince as if he himself had received it. The
sight of corpses, the sad business of necropsies, caused him real
disgust; we have often seen him go home ill from those operating
theatres. But his love of science, his desire for truth were the
stronger; he returned the next day.”
He was highly interested in the study of puerperal fever, which was
still enveloped in profound darkness. Might not the application of his
theories to the progress of surgery be realized in obstetrics? Could not
those epidemics be arrested which passed like scourges over lying-in
hospitals? It was still remembered with horror how, in the Paris
Maternity Hospital, between April 1 and May 10, 1856, 64 fatalities had
taken place out of 347 confinements. The hospital had to be closed, and
the survivors took refuge at the Lariboisière Hospital, where they
nearly all succumbed, pursued, it was thought, by the epidemic.
Dr. Tarnier, a student residing at the Maternité during that disastrous
time, related afterwards how the ignorance of the causes of puerperal
fever was such that he was sometimes called away, by one of his chiefs,
from some post-mortem business, to assist in the maternity wards; nobody
being struck by the thought of the infection which might thus be carried
from the theatre to the bed of the patient.
The discussion which arose in 1858 at the Académie de Médecine lasted
four months, and hypotheses of all kinds were brought forward. Trousseau
alone showed some prescience of the future by noticing an analogy
between infectious surgical accidents and infectious puerperal
accidents; the idea of a ferment even occurred to him. Years passed;
women of the lower classes looked upon the Maternité as the vestibule of
death. In 1864, 310 deaths occurred out of 1,350 confinement cases; in
1865, the hospital had to be closed. Works of cleansing and improvements
gave rise to a hope that the “epidemic genius” might be driven away.
“But, at the very beginning of 1866,” wrote Dr. Trélat, then
surgeon-in-chief at the Maternité, “the sanitary condition seemed
perturbed, the mortality rose in January, and in February we were
overwhelmed.” Twenty-eight deaths had occurred out of 103 cases.
Trélat enumerated various causes, bad ventilation, neighbouring wards,
etc., but where was the origin of the evil?
“Under the influence of causes which escape us,” wrote M. Léon Le Fort
about that time, “puerperal fever develops in a recently delivered
woman; she becomes a centre of infection, and, if that infection is
freely exercised, the epidemic is constituted.”
Tarnier, who took Trélat’s place at the Maternité, in 1867, had been for
eleven years so convinced of the infectious nature of puerperal fever
that he thought but of arresting the evil by every possible means of
defence, the first of which seemed to him isolation of the patients.
In 1874, Dr. Budin, then walking the hospitals, had noted in Edinburgh
the improvement due to antisepsis, thanks to Lister. Three or four years
later, in 1877 and 1878, after having seen that, in the various
maternity hospitals of Holland, Germany, Austria, Russia and Denmark,
antisepsis was practised with success, he brought his impressions with
him to Paris. Tarnier hastened to employ carbolic acid at the Maternité
with excellent results, and his assistant, M. Bar, tried sublimate.
While that new period of victory over fatal cases was beginning, Pasteur
came to the Académie de Médecine, having found, in certain puerperal
infections, a microbe in the shape of a chain or chaplet, which lent
itself very well to culture.
“Pasteur,” wrote M. Roux, “does not hesitate to declare that that
microscopic organism is the most frequent cause of infection in recently
delivered women. One day, in a discussion on puerperal fever at the
Academy, one of his most weighty colleagues was eloquently enlarging
upon the causes of epidemics in lying-in hospitals; Pasteur interrupted
him from his place. ‘None of those things cause the epidemic; it is the
nursing and medical staff who carry the microbe from an infected woman
to a healthy one.’ And as the orator replied that he feared that microbe
would never be found, Pasteur went to the blackboard and drew a diagram
of the chain-like organism, saying: ‘There, that is what it is like!’
His conviction was so deep that he could not help expressing it
forcibly. It would be impossible now to picture the state of surprise
and stupefaction into which he would send the students and doctors in
hospitals, when, with an assurance and simplicity almost disconcerting
in a man who was entering a lying-in ward for the first time, he
criticized the appliances, and declared that all the linen should be put
into a sterilizing stove.”
Pasteur was not satisfied with offering advice and criticism, making for
himself irreconcilable enemies amongst those who were more desirous of
personal distinction than of the progress of Science. In order the
better to convince those who still doubted, he affirmed that, in a badly
infected patient--what he usually and sorrowfully called an _invaded_
patient--he could bring the microbe into evidence by a simple pin prick
on the finger tip of the unhappy woman doomed to die the next day.
“And he did so,” writes M. Roux. “In spite of the tyranny of medical
education which weighed down the public mind, some students were
attracted, and came to the laboratory to examine more closely those
matters, which allowed of such precise diagnosis and such confident
prognosis.”
What struggles, what efforts, were necessary before it could be
instilled into every mind that a constant watch must be kept in the
presence of those invisible foes, ready to invade the human body through
the least scratch--that surgeons, dressers and nurses may become causes
of infection and propagators of death through forgetfulness! and before
the theory of germs and the all powerfulness of microbes could be put
under a full light à propos of that discussion on puerperal fever!
But Pasteur was supported and inspired during that period, perhaps the
most fruitful of his existence, by the prescience that those notions
meant the salvation of human lives, and that mothers need no longer be
torn by death from the cradle of their new-born infants.
“I shall force them to see; they will have to see!” he repeated with a
holy wrath against doctors who continued to talk, from their study or at
their clubs, with some scepticism, of those newly discovered little
creatures, of those ultra-microscopic parasites, trying to moderate
enthusiasm and even confidence.
An experimental fact which occurred about that time was followed with
interest, not only by the Académie des Sciences, but by the general
public, whose attention was beginning to be awakened. A professor at the
Nancy Faculty, M. Feltz, had announced to the Académie des Sciences in
March, 1879, that, in the blood abstracted from a woman, who had died at
the Nancy Hospital of puerperal fever, he had found motionless
filaments, simple or articulated, transparent, straight or curved, which
belonged, he said, to the genus _leptothrix_. Pasteur, who in his
studies on puerperal fever had seen nothing of the kind, wrote to Dr.
Feltz, asking him to send him a few drops of that infected blood. After
receiving and examining the sample, Pasteur hastened to inform M. Feltz
that that leptothrix was no other than the bacillus anthracis. M. Feltz,
much surprised and perplexed, declared himself ready to own his error
and to proclaim it if he were convinced by examining blood infected by
charbon, and which, he said, he should collect wherever he could find
it. Pasteur desired to save him that trouble, and offered to send him
three little guinea-pigs alive, but inoculated, the one with the
deceased woman’s blood, the other with the bacteridia of
charbon-infected blood from Chartres, the third with some
charbon-infected blood from a Jura cow.
The three rodents were inoculated on May 12, at three o’clock in the
afternoon, and arrived, living, at Nancy, on the morning of the
thirteenth. They died on the fourteenth, in the laboratory of M. Feltz,
who was thus able to observe them with particular attention until their
death.
“After carefully examining the blood of the three animals after their
death, I was unable,” said M. Feltz, “to detect the least difference;
not only the blood, but the internal organs, and notably the spleen,
were affected in the same manner.”... “It is a certainty to my mind,”
he wrote to Pasteur, “that the contaminating agent has been the same in
the three cases, and that it was the bacteridium of what you call
anthrax.”
There was therefore no such thing as a leptothrix puerperalis. And it
was at a distance, without having seen the patient, that Pasteur said:
“That woman died of charbon.” With an honourable straightforwardness, M.
Feltz wrote to the Académie des Sciences relating the facts.
“It is doubly regrettable,” he concluded, “that I should not have known
charbon already last year, for, on the one hand, I might have diagnosed
the redoubtable complication presented by the case, and, on the other
hand, sought for the mode of contamination, which at present escapes me
almost completely.” All he had been able to find was that the woman, a
charwoman, lived in a little room near a stable belonging to a horse
dealer. Many animals came there; the stable might have contained
diseased ones; M. Feltz had been unable to ascertain the fact. “I must
end,” he added, “with thanks to M. Pasteur for the great kindness he has
shown me during my intercourse with him. Thanks to him, I was able to
convince myself of the identity between the bacillus anthracis and the
bacteridium found in the blood of a woman who presented all the symptoms
of grave puerperal fever.”
At the time when that convincing episode was taking place, other
experiments equally precise were being undertaken concerning splenic
fever. The question was to discover whether it would be possible to find
germs of charbon in the earth of the fields which had been contaminated
purposely, fourteen months before, by pouring culture liquids over it.
It seemed beyond all probability that those germs might be withdrawn and
isolated from the innumerable other microbes contained in the soil. It
was done, however; 500 grammes of earth were mixed with water, and
infinitesimal particles of it isolated. The spore of the bacillus
anthracis resists a temperature of 80° C. or 90° C., which would kill
any other microbe; those particles of earth were accordingly raised to
that degree of heat and then injected into some guinea-pigs, several of
which died of splenic fever. It was therefore evident that flocks were
exposed to infection merely by grazing over certain fields in that land
of the Beauce. For it was sufficient that some infected blood should
have remained on the ground, for germs of bacteridia to be found there,
perhaps years later. How often was such blood spilt as a dead animal was
being taken to the knacker’s yard or buried on the spot! Millions of
bacteridia, thus scattered on and below the surface of the soil,
produced their spores, seeds of death ready to germinate.
And yet negative facts were being opposed to these positive facts, and
the theory of spontaneity invoked! “It is with deep sorrow,” said
Pasteur at the Académie de Médecine on November 11, 1873, “that I so
frequently find myself obliged to answer thoughtless contradiction; it
also grieves me much to see that the medical Press speaks of these
discussions in apparent ignorance of the true principles of experimental
method....
“That aimlessness of criticism seems explicable to me, however, by this
circumstance--that Medicine and Surgery are, I think, going through a
crisis, a transition. There are two opposite currents, that of the old
and that of the new-born doctrine; the first, still followed by
innumerable partisans, rests on the belief in the spontaneity of
transmissible diseases; the second is the theory of germs, of the living
contagium with all its legitimate consequences....”
The better to point out that difference between epochs, Pasteur
respectfully advised M. Bouillaud, who was taking part in the
discussion, to read over Littré’s _Medicine and Physicians_, and to
compare with present ideas the chapter on epidemics written in 1836,
four years after the cholera which had spread terror over Paris and over
France. “Poisons and venoms die out on the spot after working the evil
which is special to them,” wrote Littré, “and are not reproduced in the
body of the victim, but virus and miasmata are reproduced and
propagated. Nothing is more obscure to physiologists than those
mysterious combinations of organic elements; but there lies the dark
room of sickness and of death which we must try to open.” “Among
epidemic diseases,” said Littré in another passage equally noted by
Pasteur, “some occupy the world and decimate nearly all parts of it,
others are limited to more or less wide areas. The origin of the latter
may be sought either in local circumstances of dampness, of marshy
ground, of decomposing animal or vegetable matter, or in the changes
which take place in men’s mode of life.”
“If I had to defend the novelty of the ideas introduced into medicine by
my labours of the last twenty years,” wrote Pasteur from Arbois in
September, 1879, “I should invoke the significant spirit of Littré’s
words. Such was then the state of Science in 1836, and those ideas on
the etiology of great epidemics were those of one of the most advanced
and penetrating minds of the time. I would observe, contrarily to
Littré’s opinion, that nothing proves the spontaneity of great
epidemics! As we have lately seen the phylloxera, imported from America,
invade Europe, so it might be that the causes of great pests were
originated, unknowingly to stricken countries, in other countries which
had had fortuitous contact with the latter. Imagine a microscopic being,
inhabiting some part of Africa and existing on plants, on animals, or
even on men, and capable of communicating a disease to the white race;
if brought to Europe by some fortuitous circumstance, it may become the
occasion of an epidemic....”
And, writing later, about the same passage: “Nowadays, if an article had
to be written on the same subject, it would certainly be the idea of
living ferments and microscopic beings and germs which would be
mentioned and discussed as a cause. That is the great progress,” added
Pasteur with legitimate pride, “in which my labours have had so large a
share. But it is characteristic of Science and Progress that they go on
opening new fields to our vision; the scientist, who is exploring the
unknown, resembles the traveller who perceives further and higher
summits as he reaches greater altitudes. In these days, more infectious
diseases, more microscopic beings appear to the mind as things to be
discovered, the discovery of which will render a wonderful account of
pathological conditions and of their means of action and propagation, of
self-multiplication within and destruction of the organism. The point of
view is very different from Littré’s!!”
On his return to Paris, Pasteur, his mind overflowing with ideas, had
felt himself impelled to speak again, to fight once more the fallacious
theory of the spontaneity of transmissible diseases. He foresaw the
triumph of the germ theory arising from the ruin of the old
doctrines--at the price, it is true, of many efforts, many struggles,
but those were of little consequence to him.
The power of his mind, the radiating gifts that he possessed, were such
that his own people were more and more interested in the laboratory,
every one trying day by day to penetrate further into Pasteur’s
thoughts. His family circle had widened; his son and his daughter had
married, and the two new-comers had soon been initiated into past
results and recent experiments. He had, in his childhood and youth, been
passionately loved by his parents and sisters, and now, in his middle
age, his tenderness towards his wife and children was eagerly repaid by
the love they bore him. He made happiness around him whilst he gave
glory to France.