1860--1864
On January 30, 1860, the Académie des Sciences conferred on Pasteur the
Prize for Experimental Physiology. Claude Bernard, who drew up the
report, recalled how much Pasteur’s experiments in alcoholic
fermentation, lactic fermentation, the fermentation of tartaric acid,
had been appreciated by the Académie. He dwelt upon the great
physiological interest of the results obtained. “It is,” he concluded,
“by reason of that physiological tendency in Pasteur’s researches, that
the Commission has unanimously selected him for the 1859 Prize for
Experimental Physiology.”
That same January, Pasteur wrote to Chappuis: “I am pursuing as best I
can these studies on fermentation which are of great interest, connected
as they are with the impenetrable mystery of Life and Death. I am hoping
to mark a decisive step very soon by solving, without the least
confusion, the celebrated question of spontaneous generation. Already I
could speak, but I want to push my experiments yet further. There is so
much obscurity, together with so much passion, on both sides, that I
shall require the accuracy of an arithmetical problem to convince my
opponents by my conclusions. I intend to attain even that.”
This progress was depicted to his father in the following letter, dated
February 7, 1860--
“I think I told you that I should read a second and last lecture on my
old researches on Friday, at the Chemical Society, before several
members of the Institute--amongst others, Messrs. Dumas and Claude
Bernard. That lecture has had the same success as the first. M. Biot
heard about it the next day through some distinguished persons who were
in the audience, and sent for me in order to kindly express his great
satisfaction.
“After I had finished, M. Dumas, who occupied the chair, rose and
addressed me in these words. After praising the zeal I had brought to
this novel kind of teaching at the Society’s request, and the _so great
penetration I had given proof of, in the course of the work I had just
expounded, he added, ‘The Académie, sir, rewarded you a few days ago for
other profound researches; your audience of this evening will applaud
you as one of the most distinguished professors we possess._’
“All I have underlined was said in those very words by M. Dumas, and was
followed by great applause.
“All the students of the scientific section of the Ecole Normale were
present; they felt deeply moved and several of them have expressed their
emotion to me.
“As for myself, I saw the realization of what I had foreseen. You know
how I have always told you confidentially that time would see the growth
of my researches on the molecular dissymmetry of natural organic
products. Founded as they were on varied notions borrowed from divers
branches of science--crystallography, physics, and chemistry--those
studies could not be followed by most scientists so as to be fully
understood. On this occasion I presented them in the aggregate with some
clearness and power and every one was struck by their importance.
“It is not by their form that these two lectures have delighted my
hearers, it is by their contents; it is the future reserved to those
great results, so unexpected, and opening such entirely new vistas to
physiology. I have dared to say so, for at these heights all sense of
personality disappears, and there only remains that sense of dignity
which is ever inspired by true love of science.
“God grant that by my persevering labours I may bring a little stone to
the frail and ill-assured edifice of our knowledge of those deep
mysteries of Life and Death where all our intellects have so lamentably
failed.
“P.S.--Yesterday I presented to the Academy my researches on spontaneous
generation; they seemed to produce a great sensation. More later.”
When Biot heard that Pasteur wished to tackle this study of spontaneous
generation, he interposed, as he had done seven years before, to arrest
him on the verge of his audacious experiments on the part played by
dissymmetrical forces in the development of life. Vainly Pasteur,
grieved at Biot’s disapprobation, explained that this question, in the
course of such researches, had become an imperious necessity; Biot
would not be convinced. But Pasteur, in spite of his quasi-filial
attachment to Biot, could not stop where he was; he had to go through to
the end.
“You will never find your way out,” cried Biot.
“I shall try,” said Pasteur modestly.
Angry and anxious, Biot wished Pasteur to promise that he would
relinquish these apparently hopeless researches. J. B. Dumas, to whom
Pasteur related the more than discouraging remonstrances of Biot,
entrenched himself behind this cautious phrase--
“I would advise no one to dwell too long on such a subject.”
Senarmont alone, full of confidence in the ingenious curiosity of the
man who could read nature by dint of patience, said that Pasteur should
be allowed his own way.
It is regrettable that Biot--whose passion for reading was so
indefatigable that he complained of not finding enough books in the
library at the Institute--should not have thought of writing the history
of this question of spontaneous generation. He could have gone back to
Aristotle, quoted Lucretius, Virgil, Ovid, Pliny. Philosophers, poets,
naturalists, all believed in spontaneous generation. Time went on, and
it was still believed in. In the sixteenth century, Van Helmont--who
should not be judged by that one instance--gave a celebrated recipe to
create mice: any one could work that prodigy by putting some dirty linen
in a receptacle, together with a few grains of wheat or a piece of
cheese. Some time later an Italian, Buonanni, announced a fact no less
fantastic: certain timberwood, he said, after rotting in the sea,
produced worms which engendered butterflies, and those butterflies
became birds.
Another Italian, less credulous, a poet and a physician, Francesco Redi,
belonging to a learned society calling itself The Academy of Experience,
resolved to carefully study one of those supposed phenomena of
spontaneous generation. In order to demonstrate that the worms found in
rotten meat did not appear spontaneously, he placed a piece of gauze
over the meat. Flies, attracted by the odour, deposited their eggs on
the gauze. From those eggs were hatched the worms, which had until then
been supposed to begin life spontaneously in the flesh itself. This
simple experiment marked some progress. Later on another Italian, a
medical professor of Padua, Vallisneri, recognized that the grub in a
fruit is also hatched from an egg deposited by an insect before the
development of the fruit.
The theory of spontaneous generation, still losing ground, appeared to
be vanquished when the invention of the microscope at the end of the
seventeenth century brought fresh arguments to its assistance. Whence
came those thousands of creatures, only distinguishable on the slide of
the microscope, those infinitely small beings which appeared in rain
water as in any infusion of organic matter when exposed to the air? How
could they be explained otherwise than through spontaneous generation,
those bodies capable of producing 1,000,000 descendants in less than
forty-eight hours.
The world of salons and of minor courts was pleased to have an opinion
on this question. The Cardinal of Polignac, a diplomat and a man of
letters, wrote in his leisure moments a long Latin poem entitled the
_Anti-Lucretius_. After scouting Lucretius and other philosophers of the
same school, the cardinal traced back to one Supreme Foresight the
mechanism and organization of the entire world. By ingenious
developments and circumlocutions, worthy of the Abbé Delille, the
cardinal, while vaunting the wonders of the microscope, which he called
“eye of our eye,” saw in it only another prodigy offered us by Almighty
Wisdom. Of all those accumulated and verified arguments, this simple
notion stood out: “The earth, which contains numberless germs, has not
produced them. Everything in this world has its germ or seed.”
Diderot, who disseminated so many ideas (since borrowed by many people
and used as if originated by them), wrote in some tumultuous pages on
nature: “Does living matter combine with living matter? how? and with
what result? And what about dead matter?”
About the middle of the eighteenth century the problem was again raised
on scientific ground. Two priests, one an Englishman, Needham, and the
other an Italian, Spallanzani, entered the lists. Needham, a great
partisan of spontaneous generation, studied with Buffon some microscopic
animalculæ. Buffon afterwards built up a whole system which became
fashionable at that time. The force which Needham found in matter, a
force which he called productive or vegetative, and which he regarded as
charged with the formation of the organic world, Buffon explained by
saying that there are certain primitive and incorruptible parts common
to animals and to vegetables. These organic molecules cast themselves
into the moulds or shapes which constituted different beings. When one
of those moulds was destroyed by death, the organic molecules became
free; ever active, they worked the putrefied matter, appropriating to
themselves some raw particles and forming, said Buffon, “by their
reunion, a multitude of little organized bodies, of which some, like
earthworms, and fungi, seem to be fair-sized animals or vegetables, but
of which others, in almost infinite numbers, can only be seen through
the microscope.”
All those bodies, according to him, only existed through spontaneous
generation. Spontaneous generation takes place continually and
universally after death and sometimes during life. Such was in his view
the origin of intestinal worms. And, carrying his investigations
further, he added, “The eels in flour paste, those of vinegar, all those
so-called microscopic animals, are but different shapes taken
spontaneously, according to circumstances, by that ever active matter
which only tends to organization.”
The Abbé Spallanzani, armed with a microscope, studied these
infinitesimal beings. He tried to distinguish them and their mode of
life. Needham had affirmed that by enclosing putrescible matter in vases
and by placing those vases on warm ashes, he produced animalculæ.
Spallanzani suspected: firstly that Needham had not exposed the vases to
a sufficient degree of heat to kill the seeds which were inside; and
secondly, that seeds could easily have entered those vases and given
birth to animalculæ, for Needham had only closed his vases with cork
stoppers, which are very porous.
“I repeated that experiment with more accuracy,” wrote Spallanzani. “I
used hermetically sealed vases. I kept them for an hour in boiling
water, and after having opened them and examined their contents within a
reasonable time I found not the slightest trace of animalculæ, though I
had examined with the microscope the infusions from nineteen different
vases.”
Thus dropped to the ground, in Spallanzani’s eyes, Needham’s singular
theory, this famous vegetative force, this occult virtue. Yet Needham
did not own himself beaten. He retorted that Spallanzani had much
weakened, perhaps destroyed, the vegetative force of the infused
substances by leaving his vases in boiling water during an hour. He
advised him to try with less heat.
The public took an interest in this quarrel. In an opuscule entitled
_Singularities of Nature_ (1769), Voltaire, a born journalist, laughed
at Needham, whom he turned into an Irish Jesuit to amuse his readers.
Joking on this race of so-called eels which began life in the gravy of
boiled mutton, he said: “At once several philosophers exclaimed at the
wonder and said, ‘There is no germ; all is made, all is regenerated by a
vital force of nature.’ ‘Attraction,’ said one; ‘Organized matter,’ said
another, ‘they are organic molecules which have found their casts.’
Clever physicists were taken in by a Jesuit.”
In those pages, lightly penned, nothing remained of what Voltaire called
“the ridiculous mistake, the unfortunate experiments of Needham, so
triumphantly refuted by M. Spallanzani and rejected by whoever has
studied nature at all.” “It is now demonstrated to sight and to reason
that there is no vegetable, no animal but has its own germ.” In his
_Philosophic Dictionary_, at the word God, “It is very strange,” said
Voltaire, “that men should deny a creator and yet attribute to
themselves the power of creating eels!” The Abbé Needham, meeting with
these religious arguments, rather unexpected from Voltaire, endeavoured
to prove that the hypothesis of spontaneous generation was in perfect
accordance with religious beliefs. But both on Needham’s side and on
Spallanzani’s there was a complete lack of conclusive proofs.
Philosophic argumentation always returned to the fore. As recently as
1846 Ernest Bersot (a moralist who became later a director of the Ecole
Normale) wrote in his book on Spiritualism: “The doctrine of spontaneous
generation pleases simplicity-loving minds; it leads them far beyond
their own expectations. But it is yet only a private opinion, and, were
it recognized, its virtue would have to be limited and narrowed down to
the production of a few inferior animals.”
That doctrine was about to be noisily re-introduced.
* * * * *
On December 20, 1858, a correspondent of the Institute, M. Pouchet,
director of the Natural History Museum of Rouen, sent to the Académie
des Sciences a _Note on Vegetable and Animal Proto-organisms
spontaneously Generated in Artificial Air and in Oxygen Gas_. The note
began thus: “At this time when, seconded by the progress of science,
several naturalists are endeavouring to reduce the domain of spontaneous
generation or even to deny its existence altogether, I have undertaken a
series of researches with the object of elucidating this vexed
question.” Pouchet, declaring that he had taken excessive precautions to
preserve his experiments from any cause of error, proclaimed that he was
prepared to demonstrate that “animals and plants could be generated in a
medium absolutely free from atmospheric air, and in which, therefore, no
germ of organic bodies could have been brought by air.”
On one copy of that communication, the opening of a four years’
scientific campaign, Pasteur had underlined the passages which he
intended to submit to rigorous experimentation. The scientific world was
discussing the matter; Pasteur set himself to work.
A new installation, albeit a summary one, allowed him to attempt some
delicate experiments. At one of the extremities of the façade of the
Ecole Normale, on the same line as the doorkeeper’s lodge, a pavilion
had been built for the school architect and his clerk. Pasteur succeeded
in obtaining possession of this small building, and transformed it into
a laboratory. He built a drying stove under the staircase; though he
could only reach the stove by crawling on his knees, yet this was better
than his old attic. He also had a pleasant surprise--he was given a
curator. He had deserved one sooner, for he had founded the institution
of _agrégés préparateurs_. Remembering his own desire, on leaving the
Ecole Normale, to have a year or two for independent study, he had
wished to facilitate for others the obtaining of those few years of
research and perhaps inspiration. Thanks to him, five places as
laboratory curators were exclusively reserved to Ecole Normale students
who had taken their degree (_agrégés_). The first curator who entered
the new laboratory was Jules Raulin, a young man with a clear and
sagacious mind, a calm and tenacious character, loving difficulties for
the sake of overcoming them.
Pasteur began by the microscopic study of atmospheric air. “If germs
exist in atmosphere,” he said, “could they not be arrested on their
way?” It then occurred to him to draw--through an aspirator--a current
of outside air through a tube containing a little plug of cotton wool.
The current as it passed deposited on this sort of filter some of the
solid corpuscles contained in the air; the cotton wool often became
black with those various kinds of dust. Pasteur assured himself that
amongst various detritus those dusts presented spores and germs. “There
are therefore in the air some organized corpuscles. Are they germs
capable of vegetable productions, or of infusions? That is the question
to solve.” He undertook a series of experiments to demonstrate that the
most putrescible liquid remained pure indefinitely if placed out of the
reach of atmospheric dusts. But it was sufficient to place in a pure
liquid a particle of the cotton-wool filter to obtain an immediate
alteration.
A year before starting any discussion Pasteur wrote to Pouchet that the
results which he had attained were “not founded on facts of a faultless
exactitude. I think you are wrong, not in believing in spontaneous
generation (for it is difficult in such a case not to have a
preconceived idea), but in affirming the existence of spontaneous
generation. In experimental science it is always a mistake not to doubt
when facts do not compel affirmation.... In my opinion, the question is
whole and untouched by decisive proofs. What is there in air which
provokes organization? Are they germs? is it a solid? is it a gas? is it
a fluid? is it a principle such as ozone? All this is unknown and
invites experiment.”
After a year’s study, Pasteur reached this conclusion: “Gases, fluids,
electricity, magnetism, ozone, things known or things occult, there is
nothing in the air that is conditional to life, except the germs that it
carries.”
Pouchet defended himself vigorously. To suppose that germs came from air
seemed to him impossible. How many millions of loose eggs or spores
would then be contained in a cubic millimetre of atmospheric air?
“What will be the outcome of this giant’s struggle?” grandiloquently
wrote an editor of the _Moniteur Scientifique_ (April, 1860). Pouchet
answered this anonymous writer by advising him to accept the doctrine of
spontaneous generation adopted of old by so many “men of genius.”
Pouchet’s principal disciple was a lover of science and of letters, M.
Nicolas Joly, an _agrégé_ of natural science, doctor of medicine, and
professor of physiology at Toulouse. He himself had a pupil, Charles
Musset, who was preparing a thesis for his doctor’s degree under the
title: _New Experimental Researches on Heterogenia, or Spontaneous
Generation_. By the words heterogenia or spontaneous generation Joly
and Musset agreed in affirming that “they did not mean a creation out of
nothing, but the production of a new organized being, lacking parents,
and of which the primordial elements are drawn from ambient organic
matter.”
Thus supported, Pouchet multiplied objections to the views of Pasteur,
who had to meet every argument. Pasteur intended to narrow more and more
the sphere of discussion. It was an ingenious operation to take the
dusts from a cotton-wool filter, to disseminate them in a liquid, and
thus to determine the alteration of that liquid; but the cotton wool
itself was an organic substance and might be suspected. He therefore
substituted for the cotton wool a plug of asbestos fibre, a mineral
substance. He invented little glass flasks with a long curved neck; he
filled them with an alterable liquid, which he deprived of germs by
ebullition; the flask was in communication with the outer air through
its curved tube, but the atmospheric germs were deposited in the curve
of the neck without reaching the liquid; in order that alteration should
take place, the vessel had to be inclined until the point where the
liquid reached the dusts in the neck.
But Pouchet said, “How could germs contained in the air be numerous
enough to develop in every organic infusion? Such a crowd of them would
produce a thick mist as dense as iron.” Of all the difficulties this
last seemed to Pasteur the hardest to solve. Could it not be that the
dissemination of germs was more or less thick according to places?
“Then,” cried the heterogenists, “there would be sterile zones and
fecund zones, a most convenient hypothesis, indeed!” Pasteur let them
laugh whilst he was preparing a series of flasks reserved for divers
experiments. If spontaneous generation existed, it should invariably
occur in vessels filled with the same alterable liquid. “Yet it is ever
possible,” affirmed Pasteur, “to take up in certain places a notable
though limited volume of ordinary air, having been submitted to no
physical or chemical change, and still absolutely incapable of producing
any alteration in an eminently putrescible liquor.” He was ready to
prove that nothing was easier than to increase or to reduce the number
either of the vessels where productions should appear or of the vessels
where those productions should be lacking. After introducing into a
series of flasks of a capacity of 250 cubic centimetres a very easily
corrupted liquid, such as yeast water, he submitted each flask to
ebullition. The neck of those vessels was ended off in a vertical point.
Whilst the liquid was still boiling, he closed, with an enameller’s
lamp, the pointed opening through which the steam had rushed out, taking
with it all the air contained in the vessel. Those flasks were indeed
calculated to satisfy both partisans or adversaries of spontaneous
generation. If the extremity of the neck of one of these vessels was
suddenly broken, all the ambient air rushed into the flask, bringing in
all the suspended dusts; the bulb was closed again at once with the
assistance of a jet of flame. Pasteur could then carry it away and place
it in a temperature of 25-30° C., quite suitable for the development of
germs and mucors.
In those series of tests some flasks showed some alteration, others
remained pure, according to the place where the air had been admitted.
During the beginning of the year 1860 Pasteur broke his bulb points and
enclosed ordinary air in many different places, including the cellars of
the Observatory of Paris. There, in that zone of an invariable
temperature, the absolutely calm air could not be compared to the air he
gathered in the yard of the same building. The results were also very
different: out of ten vessels opened in the cellar, closed again and
placed in the stove, only one showed any alteration; whilst eleven
others, opened in the yard, all yielded organized bodies.
In a letter to his father (June, 1860), Pasteur wrote: “I have been
prevented from writing by my experiments, which continue to be very
curious. But it is such a wide subject that I have almost too many ideas
of experiments. I am still being contradicted by two naturalists, M.
Pouchet of Rouen and M. Joly of Toulouse. But I do not waste my time in
answering them; they may say what they like, truth is on my side. They
do not know how to experiment; it is not an easy art; it demands,
besides certain natural qualities, a long practice which naturalists
have not generally acquired nowadays.”
When the long vacation approached, Pasteur, who intended to go on a
voyage of experiments, laid in a store of glass flasks. He wrote to
Chappuis, on August 10, 1860: “I fear from your letter that you will not
go to the Alps this year.... Besides the pleasure of having you for a
guide, I had hoped to utilize your love of science by offering you the
modest part of curator. It is by some study of air on heights afar from
habitations and vegetation that I want to conclude my work on so-called
spontaneous generation. The real interest of that work for me lies in
the connection of this subject with that of ferments which I shall take
up again November.”
Pasteur started for Arbois, taking with him seventy-three flasks; he
opened twenty of them not very far from his father’s tannery, on the
road to Dôle, along an old road, now a path which leads to the mount of
the Bergère. The vine labourers who passed him wondered what this
holiday tourist could be doing with all those little phials; no one
suspected that he was penetrating one of nature’s greatest secrets.
“What would you have?” merrily said his old friend, Jules Vercel; “it
amuses him!” Of those twenty vessels, opened some distance away from any
dwelling, eight yielded organized bodies.
Pasteur went on to Salins and climbed Mount Poupet, 850 metres above the
sea-level. Out of twenty vessels opened, only five were altered. Pasteur
would have liked to charter a balloon in order to prove that the higher
you go the fewer germs you find, and that certain zones absolutely pure
contain none at all. It was easier to go into the Alps.
He arrived at Chamonix on September 20, and engaged a guide to make the
ascent of the Montanvert. The very next morning this novel sort of
expedition started. A mule carried the case of thirty-three vessels,
followed very closely by Pasteur, who watched over the precious burden
and walked alongside of precipices supporting the case with one hand so
that it should not be shaken.
When the first experiments were started an incident occurred. Pasteur
has himself related this fact in his report to the Académie. “In order
to close again the point of the flasks after taking in the air, I had
taken with me an eolipyle spirit-lamp. The dazzling whiteness of the ice
in the sunlight was such that it was impossible to distinguish the jet
of burning alcohol, and as moreover that was slightly moved by the wind,
it never remained on the broken glass long enough to hermetically seal
my vessel. All the means I might have employed to make the flame visible
and consequently directable would inevitably have given rise to causes
of error by spreading strange dusts into the air. I was therefore
obliged to bring back to the little inn of Montanvert, unsealed, the
flasks which I had opened on the glacier.”
The inn was a sort of hut, letting in wind and rain. The thirteen open
vessels were exposed to all the dusts in the room where Pasteur slept;
nearly all of them presented alterations.
In the meanwhile the guide was sent to Chamonix where a tinker undertook
to modify the lamp in view of the coming experiment.
The next morning, twenty flasks, which have remained celebrated in the
world of scientific investigators, were brought to the Mer de Glace.
Pasteur gathered the air with infinite precautions; he used to enjoy
relating these details to those people who call everything easy. After
tracing with a steel point a line on the glass, careful lest dusts
should become a cause of error, he began by heating the neck and fine
point of the bulb in the flame of the little spirit-lamp. Then raising
the vessel above his head, he broke the point with steel nippers, the
long ends of which had also been heated in order to burn the dusts which
might be on their surface and which would have been driven into the
vessel by the quick inrush of the air. Of those twenty flasks, closed
again immediately, only one was altered. “If all the results are
compared that I have obtained until now,” he wrote, on March 5, 1880,
when relating this journey to the Académie, “it seems to me that it can
be affirmed that the dusts suspended in atmospheric air are the
exclusive origin, the necessary condition of life in infusions.”
And in an unnoticed little sentence, pointing already then to the goal
he had in view, “What would be most desirable would be to push those
studies far enough to prepare the road for a serious research into the
origin of various diseases.” The action of those little beings, agents
not only of fermentation but also of disorganization and putrefaction,
already dawned upon him.
While Pasteur was going from the Observatoire cellars to the Mer de
Glace, Pouchet was gathering air on the plains of Sicily, making
experiments on Etna, and on the sea. He saw everywhere, he wrote, “air
equally favourable to organic genesis, whether surcharged with detritus
in the midst of our populous cities, or taken on the summit of a
mountain, or on the sea, where it offers extreme purity. With a cubic
decimetre of air, taken where you like, I affirm that you can ever
produce legions of microzoa.”
And the heterogenists proclaimed in unison that “everywhere, strictly
everywhere, air is constantly favourable to life.” Those who followed
the debate nearly all leaned towards Pouchet. “I am afraid,” wrote a
scientific journalist in _La Presse_ (1860), “that the experiments you
quote, M. Pasteur, will turn against you.... The world into which you
wish to take us is really too fantastic....”
And yet some adversaries should have been struck by the efforts of a
mind which, while marching forward to establish new facts, was ever
seeking arguments against itself, and turned back to strengthen points
which seemed yet weak. In November, Pasteur returned to his studies on
fermentations in general and lactic fermentation in particular.
Endeavouring to bring into evidence the animated nature of the lactic
ferment, and to indicate the most suitable surroundings for the
self-development of that ferment, he had come across some complications
which hampered the purity and the progress of that culture. Then he had
perceived another fermentation, following upon lactic fermentation and
known as butyric fermentation. As he did not immediately perceive the
origin of this butyric acid--which causes the bad smell in rancid
butter--he ended by being struck by the inevitable coincidence between
the (then called) infusory animalculæ and the production of this acid.
“The most constantly repeated tests,” he wrote in February, 1861, “have
convinced me that the transformation of sugar, mannite and lactic acid
into butyric acid is due exclusively to those Infusories, and they must
be considered as the real butyric ferment.” Those vibriones that Pasteur
described as under the shape of small cylindric rods with rounded ends,
sliding about, sometimes in a chain of three or four articles, he sowed
in an appropriate medium, as he sowed beer yeast. But, by a strange
phenomenon, “those infusory animalculæ,” he said, “live and multiply
indefinitely, without requiring the least quantity of air. And not only
do they live without air, but air actually kills them. It is sufficient
to send a current of atmospheric air during an hour or two through the
liquor where those vibriones were multiplying to cause them all to
perish and thus to arrest butyric fermentation, whilst a current of pure
carbonic acid gas passing through that same liquor hindered them in no
way. Thence this double proposition,” concluded Pasteur; “the butyric
ferment is an infusory; that infusory lives without free oxygen.” He
afterwards called anaërobes those beings which do not require air, in
opposition to the name of aërobes given to other microscopic beings who
require air to live.
Biot, without knowing all the consequences of these studies, had not
been long in perceiving that he had been far too sceptical, and that
physiological discoveries of the very first rank would be the outcome of
researches on so-called spontaneous generation. He would have wished,
before he died, not only that Pasteur should be the unanimously selected
candidate for the 1861 Zecker prize in the Chemistry Section, but also
that his friend, forty-eight years younger than himself, should be a
member of the Institute. At the beginning of 1861, there was one vacancy
in the Botanical Section. Biot took advantage of the researches pursued
by Pasteur within the last three years, to say and to print that he
should be nominated as a candidate. “I can hear the commonplace
objection: he is a chemist, a physicist, not a professional botanist....
But that very versatility, ever active and ever successful, should be a
title in his favour.... Let us judge of men by their works and not by
the destination more or less wide or narrow that they have marked out
for themselves. Pasteur made his début before the Académie in 1848, with
the remarkable treatise which contained by implication the resolution of
the paratartaric acid into its two components, right and left. He was
then twenty-six; the sensation produced is not forgotten. Since then,
during the twelve years which followed, he has submitted to your
appreciation twenty-one papers, the last ten relating to vegetable
physiology. All are full of new facts, often very unexpected, several
very far reaching, not one of which has been found inaccurate by
competent judges. If to-day, by your suffrage, you introduce M. Pasteur
into the Botanical Section, as you might safely have done for Théodore
de Saussure or Ingenhousz, you will have acquired for the Académie and
for that particular section an experimentalist of the same order as
those two great men.”
Balard, who in this academic campaign made common cause with Biot, was
also making efforts to persuade several members of the Botanical
Section. He was walking one day in the Luxembourg with Moquin-Tandon,
pouring out, in his rasping voice, arguments in favour of Pasteur.
“Well,” said Moquin-Tandon, “let us go to Pasteur’s, and if you find a
botanical work in his library I shall put him on the list.” It was a
witty form given to the scruples of the botanists. Pasteur only had
twenty-four votes; Duchartre was elected.
The study of a microscopic fungus, capable by itself of transforming
wine into vinegar, the bringing to light of the action of that
mycoderma, endowed with the power of taking oxygen from air and fixing
it upon alcohol, thus transforming the latter into acetic acid; the most
ingenious experiments to demonstrate the absolute and exclusive power of
the little plant, all gave reason to Biot’s affirmation that such skill
in the observation of inferior vegetables equalled any botanist’s claim.
Pasteur, showing that the interpretations of the causes which act in the
formation of vinegar were false, and that alone the microscopic fungus
did everything, was constantly dwelling on this power of the
infinitesimally small. “Mycoderma,” he said, “can bring the action of
combustion of the oxygen in air to bear on a number of organic materia.
If microscopic beings were to disappear from our globe, the surface of
the earth would be encumbered with dead organic matter and corpses of
all kinds, animal and vegetable. It is chiefly they who give to oxygen
its powers of combustion. Without them, life would become impossible
because death would be incomplete.”
Pasteur’s ideas on fermentation and putrefaction were being adopted by
disciples unknown to him. “I am sending you,” he wrote to his father, “a
treatise on fermentation, which was the subject of a recent competition
at the Montpellier Faculty. This work is dedicated to me by its author,
whom I do not know at all, a circumstance which shows that my results
are spreading and exciting some attention.
“I have only read the last pages, which have pleased me; if the rest is
the same, it is a very good _résumé_, entirely conceived in the new
direction of my labours, evidently well understood by this young doctor.
“M. Biot is very well, only suffering a little from insomnia. He has,
fortunately for his health, finished that great account of my former
results which will be the greatest title I can have to the esteem of
scientists.”
Biot died without having realized his last wish, which was to have
Pasteur for a colleague. It was only at the end of the year 1862 that
Pasteur was nominated by the Mineralogical Section for the seat of
Senarmont. This new candidature did not go without a hitch. In his study
on tartrates, Pasteur, as will be remembered, had discovered that their
crystalline forms were hemihedral. When he examined the characteristic
faces, he held the crystal in a particular way and said: “It is
hemihedral on the right side.” A German mineralogist, named
Rammelsberg, holding the crystal in the opposite direction, said: “It is
hemihedral on the left side.” It was a mere matter of conventional
orientation; nothing was changed in the scientific results announced by
Pasteur. But some adversaries made a weapon of that inverted crystal;
not a dangerous weapon, thought Pasteur at first, fancying that a few
words would clear the misunderstanding. But the campaign persisted, with
insinuations, murmurs, whisperings. When Pasteur saw this simple
difference in the way the crystal was held stigmatised as a cause of
error, he desired to cut short this quarrel made in Germany. He then had
with him no longer Raulin, but M. Duclaux, who was beginning his
scientific life. M. Duclaux remembers one day when Pasteur, seeing that
incontrovertible arguments were required, sent for a cabinet maker with
his tools. He superintended the making of a complete wooden set of the
crystalline forms of tartrates, a gigantic set, such as Gulliver might
have seen in Brobdingnag if he had studied geometrical forms in that
island. A coating of coloured paper finished the work; green paper
marked the hemihedral face. A member of the Philomathic Society, Pasteur
asked the Society to give up the meeting of November 8, 1862, to the
discussion of that subject. Several of his colleagues vainly endeavoured
to dissuade him from that intention; Pasteur hearkened to no one. He
took with him his provision of wooden crystals, and gave a vivid and
impassioned lecture. “If you know the question,” he asked his
adversaries, “where is your conscience? If you know it not, why meddle
with it?” And with one of his accustomed sudden turns, “What is all
this?” he added. “One of those incidents to which we all, more or less,
are exposed by the conditions of our career; no bitterness remains
behind. Of what account is it in the presence of those mysteries, so
varied, so numerous, that we all, in divers directions, are working to
clear? It is true I have had recourse to an unusual means of defending
myself against attacks not openly published, but I think that means was
safe and loyal, and deferential towards you. And,” he added, thinking of
Biot and Senarmont, “will you have my full confession? You know that I
had during fifteen years the inestimable advantage of the intercourse of
two men who are no more, but whose scientific probity shone as one of
the beacons of the Académie des Sciences. Before deciding on the course
I have now followed, I questioned my memory and endeavoured to revive
their advice, and it seemed to me that they would not have disowned me.”
M. Duclaux said about this meeting: “Pasteur has since then won many
oratorical victories. I do not know of a greater one than that deserved
by that acute and penetrating improvisation. He was still much heated as
we were walking back to the Rue d’Ulm, and I remember making him laugh
by asking him why, in the state of mind he was in, he had not concluded
by hurling his wooden crystals at his adversaries’ heads.”
On December 8, 1862, Pasteur was elected a member of the Académie des
Sciences; out of sixty voters he received thirty-six suffrages.
The next morning, when the gates of the Montparnasse cemetery were
opened, a woman walked towards Biot’s grave with her hands full of
flowers. It was Mme. Pasteur who was bringing them to him who lay there
since February 5, 1862, and who had loved Pasteur with so deep an
affection.
A letter picked up at a sale of autographs, one of the last Biot wrote,
gives a finishing touch to his moral portrait. It is addressed to an
unknown person discouraged with this life. “Sir,--The confidence you
honour me with touches me. But I am not a physician of souls. However,
in my opinion, you could not do better than seek remedies to your moral
suffering in work, religion, and charity. A useful work taken up with
energy and persevered in will revive by occupation the forces of your
mind. Religious feelings will console you by inspiring you with
patience. Charity manifested to others will soften your sorrows and
teach you that you are not alone to suffer in this life. Look around
you, and you will see afflicted ones more to be pitied than yourself.
Try to ease their sufferings; the good you will do to them will fall
back upon yourself and will show you that a life which can thus be
employed is not a burden which cannot, which must not be borne.”
On his entering the Académie des Sciences, Balard and Dumas advised
Pasteur to let alone his wooden crystals and to continue his studies on
ferments. He undertook to demonstrate that “the hypothesis of a
phenomenon of mere contact is not more admissible than the opinion which
placed the ferment character exclusively in dead albuminoid matter.”
Whilst continuing his researches on beings which could live without air,
he tried, as he went along, à propos of spontaneous generation, to find
some weak point in his work. Until now the liquids he had used, however
alterable they were, had been brought up to boiling point. Was there not
some new and decisive experiment to make? Could he not study organic
matter as constituted by life and expose to the contact of air deprived
of its germs some fresh liquids, highly putrescible, such as blood and
urine? Claude Bernard, joining in these experiments of Pasteur’s,
himself took some blood from a dog. This blood was sealed up in a glass
phial, with every condition of purity, and the phial remained in a stove
constantly heated up to 30°C. from March 3 until April 20, 1862, when
Pasteur laid it on the Académie table. The blood had suffered no sort of
putrefaction; neither had some urine treated in the same way. “The
conclusions to which I have been led by my first series of experiments,”
said Pasteur before the Académie, “are therefore applicable in all cases
to organic substances.”
While studying putrefaction, which is itself but a fermentation applied
to animal materia, while showing the marvellous power of the
infinitesimally small, he foresaw the immensity of the domain he had
conquered, as will be proved by the following incident. Some time after
the Académie election, in March, 1863, the Emperor, who took an interest
in all that took place in the small laboratory of the Rue d’Ulm, desired
to speak with Pasteur. J. B. Dumas claimed the privilege of presenting
his former pupil, and the interview took place at the Tuileries.
Napoleon questioned Pasteur with a gentle, slightly dreamy insistence.
Pasteur wrote the next day: “I assured the Emperor that all my ambition
was to arrive at the knowledge of the causes of putrid and contagious
diseases.”
In the meanwhile, the chapter on ferments was not yet closed; Pasteur
was attracted by studies on wine. At the beginning of the 1863 holidays,
just before starting for Arbois, he drew up this programme with one of
his pupils: “From the 20th to the 30th (August) preparation in Paris of
all the vessels, apparatus, products, that we must take. September 1,
departure for the Jura; installation; purchase of the products of a
vineyard. Immediate beginning of tests of all kinds. We shall have to
hurry; grapes do not keep long.”
Whilst he was preparing this vintage tour, which he intended to make
with three “Normaliens,” Duclaux, Gernez and Lechartier, the three
heterogenists, Pouchet, Joly and Musset, proposed to use that same time
in fighting Pasteur on his own ground. They started from
Bagnères-de-Luchon followed by several guides and taking with them all
kinds of provisions and some little glass flasks with a slender pointed
neck. They crossed the pass of Venasque without incident, and decided to
go further, to the Rencluse. Some isard-stalkers having come towards the
strange-looking party, they were signalled away; even the guides were
invited to stand aside. It was necessary to prevent any dusts from
reaching the bulbs, which were thus opened at 8 p.m. at a height of
2,083 metres. But eighty-three metres higher than the Montanvert did not
seem to them enough, they wished to go higher. “We shall sleep on the
mountain,” said the three scientists. Fatigue and bitter cold, they
withstood everything with the courage inspired by a problem to solve.
The next morning they climbed across that rocky chaos, and at last
reached the foot of one of the greatest glaciers of the Maladetta, 3,000
metres above the sea-level. “A very deep narrow crevasse,” says Pouchet,
“seemed to us the most suitable place for our experiments.” Four phials
(filled with a decoction of hay) were opened and sealed again with
precautions that Pouchet considered as exaggerated.
Pouchet, in his merely scientific report, does not relate the return
journey, yet more perilous than the ascent. At one of the most dangerous
places, Joly slipped, and would have rolled into a precipice, but for
the strength and presence of mind of one of the guides. All three at
last came back to Luchon, forgetful of dangers run, and glorying at
having reached 1,000 metres higher than Pasteur. They triumphed when
they saw alteration in their flasks! “Therefore,” said Pouchet, “the air
of the Maladetta, and of high mountains in general, is not incapable of
producing alteration in an eminently putrescible liquor; therefore
heterogenia or the production of a new being devoid of parents, but
formed at the expense of ambient organic matter, is for us a reality.”
The Academy of Sciences was taking more and more interest in this
debate. In November, 1863, Joly and Musset expressed a wish that the
Academy should appoint a Commission, before whom the principal
experiments of Pasteur and of his adversaries should be repeated. On
this occasion Flourens expressed his opinion thus: “I am blamed in
certain quarters for giving no opinion on the question of spontaneous
generation. As long as my opinion was not formed, I had nothing to say.
It is now formed, and I give it: M. Pasteur’s experiments are decisive.
If spontaneous generation is real, what is required to obtain
animalculæ? Air and putrescible liquor. M. Pasteur puts air and
putrescible liquor together and nothing happens. Therefore spontaneous
generation is not. To doubt further is to misunderstand the question.”
Already in the preceding year, the Académie itself had evidenced its
opinion by giving Pasteur the prize of a competition proposed in these
terms: “To attempt to throw some new light upon the question of
so-called spontaneous generation by well-conducted experiments.”
Pasteur’s treatise on _Organized Corpuscles existing in Atmosphere_ had
been unanimously preferred. Pasteur might have entrenched himself behind
the suffrages of the Academy, but begged it, in order to close those
incessant debates, to appoint the Commission demanded by Joly and
Musset.
The members of the Commission were Flourens, Dumas, Brongniart,
Milne-Edwards, and Balard. Pasteur wished that the discussion should
take place as soon as possible, and it was fixed for the first fortnight
in March. But Pouchet, Joly and Musset asked for a delay on account of
the cold. “We consider that it might compromise, perhaps prevent, our
results, to operate in a temperature which often goes below zero even in
the south of France. How do we know that it will not freeze in Paris
between the first and fifteenth of March?” They even asked the
Commission to adjourn experiments until the summer. “I am much
surprised,” wrote Pasteur, “at the delay sought by Messrs. Pouchet, Joly
and Musset; it would have been easy with a stove to raise the
temperature to the degree required by those gentlemen. For my part I
hasten to assure the Academy that I am at its disposal, and that in
summer, or in any other season, I am ready to repeat my experiments.”
Some evening scientific lectures had just been inaugurated at the
Sorbonne; such a subject as spontaneous generation was naturally on the
programme. When Pasteur entered the large lecture room of the Sorbonne
on April 7, 1864, he must have been reminded of the days of his youth,
when crowds came, as to a theatrical performance, to hear J. B. Dumas
speak. Dumas’ pupil, now a master, in his turn found a still greater
crowd invading every corner. Amongst the professors and students, such
celebrities as Duruy, Alexandre Dumas senior, George Sand, Princess
Mathilde, were being pointed out. Around them, the inevitable “smart”
people who must see everything and be seen everywhere, without whom no
function favoured by fashion would be complete; in short what is known
as the “Tout Paris.” But this “Tout Paris” was about to receive a novel
impression, probably a lasting one. The man who stood before this
fashionable audience was not one of those speakers who attempt by an
insinuating exordium to gain the good graces of their hearers; it was a
grave-looking man, his face full of quiet energy and reflective force.
He began in a deep, firm voice, evidently earnestly convinced of the
greatness of his mission as a teacher: “Great problems are now being
handled, keeping every thinking man in suspense; the unity or
multiplicity of human races; the creation of man 1,000 years or 1,000
centuries ago, the fixity of species, or the slow and progressive
transformation of one species into another; the eternity of matter; the
idea of a God unnecessary. Such are some of the questions that humanity
discusses nowadays.”
He had now, he continued, entered upon a subject accessible to
experimentation, and which he had made the object of the strictest and
most conscientious studies. Can matter organize itself? Can living
beings come into the world without having been preceded by beings
similar to them? After showing that the doctrine of spontaneous
generation had gradually lost ground, he explained how the invention of
the microscope had caused it to reappear at the end of the seventeenth
century, “in the face of those beings, so numerous, so varied, so
strange in their shapes, the origin of which was connected with the
presence of all dead vegetable and animal matter in a state of
disorganization.” He went on to say how Pouchet had taken up this study,
and to point out the errors that this new partisan of an old doctrine
had committed, errors difficult to recognize at first. With perfect
clearness and simplicity, Pasteur explained how the dusts which are
suspended in air contain germs of inferior organized beings and how a
liquid preserved, by certain precautions, from the contact of these
germs can be kept indefinitely, giving his audience a glimpse of his
laboratory methods.
“Here,” he said, “is an infusion of organic matter, as limpid as
distilled water, and extremely alterable. It has been prepared to-day.
To-morrow it will contain animalculæ, little infusories, or flakes of
mouldiness.
“I place a portion of that infusion into a flask with a long neck, like
this one. Suppose I boil the liquid and leave it to cool. After a few
days, mouldiness or animalculæ will develop in the liquid. By boiling, I
destroyed any germs contained in the liquid or against the glass; but
that infusion being again in contact with air, it becomes altered, as
all infusions do. Now suppose I repeat this experiment, but that, before
boiling the liquid, I draw (by means of an enameller’s lamp) the neck of
the flask into a point, leaving, however, its extremity open. This being
done, I boil the liquid in the flask, and leave it to cool. Now the
liquid of this second flask will remain pure not only two days, a month,
a year, but three or four years--for the experiment I am telling you
about is already four years old, and the liquid remains as limpid as
distilled water. What difference is there, then, between those two
vases? They contain the same liquid, they both contain air, both are
open! Why does one decay and the other remain pure? The only difference
between them is this: in the first case, the dusts suspended in air and
their germs can fall into the neck of the flask and arrive into contact
with the liquid, where they find appropriate food and develop; thence
microscopic beings. In the second flask, on the contrary, it is
impossible, or at least extremely difficult, unless air is violently
shaken, that dusts suspended in air should enter the vase; they fall on
its curved neck. When air goes in and out of the vase through diffusions
or variations of temperature, the latter never being sudden, the air
comes in slowly enough to drop the dusts and germs that it carries at
the opening of the neck or in the first curves.
“This experiment is full of instruction; for this must be noted, that
everything in air save its dusts can easily enter the vase and come into
contact with the liquid. Imagine what you choose in the
air--electricity, magnetism, ozone, unknown forces even, all can reach
the infusion. Only one thing cannot enter easily, and that is dust,
suspended in air. And the proof of this is that if I shake the vase
violently two or three times, in a few days it contains animalculæ or
mouldiness. Why? because air has come in violently enough to carry dust
with it.
“And, therefore, gentlemen, I could point to that liquid and say to you,
I have taken my drop of water from the immensity of creation, and I have
taken it full of the elements appropriated to the development of
inferior beings. And I wait, I watch, I question it, begging it to
recommence for me the beautiful spectacle of the first creation. But it
is dumb, dumb since these experiments were begun several years ago; it
is dumb because I have kept it from the only thing man cannot produce,
from the germs which float in the air, from Life, for Life is a germ and
a germ is Life. Never will the doctrine of spontaneous generation
recover from the mortal blow of this simple experiment.”
The public enthusiastically applauded these words, which ended the
lecture:
“No, there is now no circumstance known in which it can be affirmed that
microscopic beings came into the world without germs, without parents
similar to themselves. Those who affirm it have been duped by illusions,
by ill-conducted experiments, spoilt by errors that they either did not
perceive or did not know how to avoid.”
In the meanwhile, besides public lectures and new studies, Pasteur
succeeded in “administering” the Ecole Normale in the most complete
sense of the word. His influence was such that students acquired not a
taste but a passion for study; he directed each one in his own line, he
awakened their instincts. It was already through his wise inspiration
that five “Normaliens agrégés” should have the chance of the five
curators’ places; but his solicitude did not stop there. If some
disappointment befell some former pupil, still in that period of youth
which doubts nothing or nobody, he came vigorously to his assistance; he
was the counsellor of the future. A few letters will show how he
understood his responsibility.
A Normalien, Paul Dalimier, received 1st at the _agrégation_ of Physics
in 1858, afterwards Natural History curator at the Ecole, and who,
having taken his doctor’s degree, asked to be sent to a Faculty, was
ordered to go to the Lycée of Chaumont.
In the face of this almost disgrace he wrote a despairing letter to
Pasteur. He could do nothing more, he said, his career was ruined. “My
dear sir,” answered Pasteur, “I much regret that I could not see you
before your departure for Chaumont. But here is the advice which I feel
will be useful to you. Do not manifest your just displeasure; but
attract attention from the very first by your zeal and talent. In a
word, aggravate, by your fine discharge of your new duties, the
injustice which has been committed. The discouragement expressed in
your last letter is not worthy of a man of science. Keep but three
objects before your eyes: your class, your pupils and the work you have
begun.... Do your duty to the best of your ability, without troubling
about the rest.”
Pasteur undertook the rest himself. He went to the Ministry to complain
of the injustice and unfairness, from a general point of view, of that
nomination.
“Sir,” answered the Chaumont exile, “I have received your kind letter.
My deep respect for every word of yours will guarantee my intention to
follow your advice. I have given myself up entirely to my class. I have
found here a Physics cabinet in a deplorable state, and I have
undertaken to reorganise it.”
He had not time to finish: justice was done, and Paul Dalimier was made
_maître des conférences_ at the Ecole Normale. He died at twenty-eight.
The wish that masters and pupils should remain in touch with each other
after the three years at the Ecole Normale had already in 1859 inspired
Pasteur to write a report on the desirableness of an annual report
entitled, _Scientific Annals of the Ecole Normale_.
The initiative of pregnant ideas often is traced back to France. But,
through want of tenacity, she allows those same ideas to fall into decay
and they are taken up by other nations, transplanted, developed, until
they come back unrecognized to their mother country. Germany had seen
the possibilities of such a publication as Pasteur’s projected _Annals_.
Renan wrote about that time to the editors of the _Revue Germanique_, a
Review intended to draw France and Germany together: “In France, nothing
is made public until achieved and ripened. In Germany, a work is given
out provisionally, not as a teaching, but as an incitement to think, as
a ferment for the mind.”
Pasteur felt all the power of that intellectual ferment. In the volume
entitled _Centenary of the Ecole Normale_, M. Gernez has recalled
Pasteur’s enthusiasm when he spoke of those _Annals_. Was it not for
former pupils, away in the provinces, a means of collaborating with
their old masters and of keeping in touch with Paris?
It was in June, 1864, that Pasteur presented the first number of this
publication to the Académie des Sciences. M. Gernez, who was highly
thought of by Pasteur, has not related in the _Centenary_ that the book
opened with some of his own researches on the rotatory power of certain
liquids and their steam.
At that same time, the heterogenists had at last placed themselves at
the disposal of the Académie and were invited to meet Pasteur before the
Natural History Commission at M. Chevreul’s laboratory. “I affirm,” said
Pasteur, “that in any place it is possible to take up from the ambient
atmosphere a determined volume of air containing neither egg nor spore
and producing no generation in putrescible solutions.” The Commission
declared that, the whole contest bearing upon one simple fact, one
experiment only should take place. The heterogenists wanted to
recommence a whole series of experiments, thus reopening the discussion.
The Commission refused, and the heterogenists, unwilling to concede the
point, retired from the field, repudiating the arbiters that they had
themselves chosen.
And yet Joly had written to the Académie, “If one only of our flasks
remains pure, we will loyally own our defeat.” A scientist who later
became Permanent Secretary of the Académie des Sciences, Jamin, wrote
about this conflict: “The heterogenists, however they may have coloured
their retreat, have condemned themselves. If they had been sure of the
fact--which they had solemnly engaged to prove or to own themselves
vanquished,--they would have insisted on showing it, it would have been
the triumph of their doctrine.”
The heterogenists appealed to the public. A few days after their defeat,
Joly gave a lecture at the Faculty of Medicine. He called the trial, as
decided on by the Commission, a “circus competition”; he was applauded
by those who saw other than scientific questions in the matter. The
problem was now coming down from mountains and laboratories into the
arena of society discussions. If all comes from a germ, people said,
whence came the first germ? We must bow before that mystery, said
Pasteur; it is the question of the origin of all things, and absolutely
outside the domain of scientific research. But an invincible curiosity
exists amongst most men which cannot admit that science should have the
wisdom to content itself with the vast space between the beginning of
the world and the unknown future. Many people transform a question of
fact into a question of faith. Though Pasteur had brought into his
researches a solely scientific preoccupation, many people approved or
blamed him as the defender of a religious cause.
Vainly had he said, “There is here no question of religion, philosophy,
atheism, materialism, or spiritualism. I might even add that they do not
matter to me as a scientist. It is a question of fact; when I took it up
I was as ready to be convinced by experiments that spontaneous
generation exists as I am now persuaded that those who believe it are
blindfolded.”
It might have been thought that Pasteur’s arguments were in support of a
philosophical theory! It seemed impossible to those whose ideas came
from an ardent faith, from the influence of their surroundings, from
personal pride or from interested calculations to understand that a man
should seek truth for its own sake and with no other object than to
proclaim it. Hostilities were opened, journalists kept up the fire. A
priest, the Abbé Moigno spoke of converting unbelievers through the
proved non-existence of spontaneous generation. The celebrated novelist,
Edmond About, took up Pouchet’s cause with sparkling irony. “M. Pasteur
preached at the Sorbonne amidst a concert of applause which must have
gladdened the angels.”
Thus, among the papers and reviews of that time we can follow the divers
ideas brought out by these discussions. Guizot, then almost eighty,
touched on this problem with the slightly haughty assurance of one
conscious of having given much thought to his beliefs and destiny. “Man
has not been formed through spontaneous generation, that is by a
creative and organizing force inherent in matter; scientific observation
daily overturns that theory, by which, moreover, it is impossible to
explain the first appearance upon the earth of man in his complete
state.” And he praised “M. Pasteur, who has brought into this question
the light of his scrupulous criticism.”
Nisard was a wondering witness of what took place in the small
laboratory of the Ecole Normale. Ever preoccupied by the relations
between science and religion, he heard with some surprise Pasteur saying
modestly, “Researches on primary causes are not in the domain of
Science, which only recognizes facts and phenomena which it can
demonstrate.”
Pasteur did not disinterest himself from the great problems which he
called the eternal subjects of men’s solitary meditations. But he did
not admit the interference of religion with science any more than that
of science with religion.
His eagerness during a conflict was only equalled by his absolute
forgetfulness after the conflict was over. He answered some one who,
years later, reminded him of that past so full of attacks and praises.
“A man of science should think of what will be said of him in the
following century, not of the insults or the compliments of one day.”
Pasteur, anxious to regain lost time, hurried to return to his studies
on wine. “Might not the diseases of wines,” he said at the Académie des
Sciences in January, 1864, “be caused by organized ferments, microscopic
vegetations, of which the germs would develop when certain circumstances
of temperature, of atmospheric variations, of exposure to air, would
favour their evolution or their introduction into wines?... I have
indeed reached this result that the alterations of wines are co-existent
with the presence and multiplication of microscopic vegetations.” Acid
wines, bitter wines, “ropy” wines, sour wines, he had studied them all
with a microscope, his surest guide in recognizing the existence and
form of the evil.
As he had more particularly endeavoured to remedy the cause of the
acidity which often ruins the Jura red or white wines in the wood, the
town of Arbois, proud of its celebrated rosy and tawny wines, placed an
impromptu laboratory at his disposal during the holidays of 1864; the
expenses were all to be covered by the town. “This spontaneous offer
from a town dear to me for so many reasons,” answered Pasteur to the
Mayor and Town Council, “does too much honour to my modest labours, and
the way in which it is made covers me with confusion.” He refused it
however, fearing that the services he might render should not be
proportionate to the generosity of the Council. He preferred to camp out
with his curators in an old coffee room at the entrance of the town, and
they contented themselves with apparatus of the most primitive
description, generally made by some local tinker or shoeing smith.
The problem consisted, in Pasteur’s view, in opposing the development of
organized ferments or parasitic vegetations, causes of the diseases of
wines. After some fruitless endeavours to destroy all vitality in the
germs of these parasites, he found that it was sufficient to keep the
wine for a few moments at a temperature of 50° C. to 60° C. “I have also
ascertained that wine was never altered by that preliminary operation,
and as nothing prevents it afterwards from undergoing the gradual
action of the oxygen in the air--the only cause, as I think, of its
improvement with age--it is evident that this process offers every
advantage.”
It seems as if that simple and practical means, applicable to every
quality of wine, now only had to be tried. But not so. Every progress is
opposed by prejudice, petty jealousies, indolence even. A devoted
obstinacy is required in order to overcome this opposition. Pasteur’s
desire was that his country should benefit by his discovery. An
Englishman had written to him: “People are astonished in France that the
sale of French wines should not have become more extended here since the
Commercial Treaties. The reason is simple enough. At first we eagerly
welcomed those wines, but we soon had the sad experience that there was
too much loss occasioned by the diseases to which they are subject.”
Pasteur was in the midst of those discussions, experimental sittings,
etc., when J. B. Dumas suddenly asked of him the greatest of sacrifices,
that of leaving the laboratory.