1850--1854
From the very beginning Mme. Pasteur not only admitted, but approved,
that the laboratory should come before everything else. She would
willingly have adopted the typographic custom of the Académie des
Sciences Reports, where the word Science is always spelt with a capital
S. It was indeed impossible to live with her husband without sharing his
joys, anxieties and renewed hopes, as they appeared day by day reflected
in his admirable eyes--eyes of a rare grey-green colour like the sparkle
of a Ceylon gem. Before certain scientific possibilities, the flame of
enthusiasm shone in those deep eyes, and the whole stern face was
illumined. Between domestic happiness and prospective researches,
Pasteur’s life was complete. But this couple, who had now shared
everything for more than a year, was to suffer indirectly through the
new law on the liberty of teaching.
Devised by some as an effort at compromise between the Church and the
University, considered by others as a scope for competition against
State education, the law of 1850 brought into the Superior Council of
Public Instruction four archbishops or bishops, elected by their
colleagues. In each Department[20] an Academy Council was instituted,
and, in this parcelling out of University jurisdiction, the right of
presence was recognized as belonging to the bishop or his delegate. But
all these advantages did not satisfy those who called themselves
Catholics before everything else. The rupture between Louis Veuillot on
one side and, on the other, Falloux and Montalembert, the principal
authors of this law, dates from that time.
“What we understood by the liberty of teaching,” wrote Louis Veuillot,
“was not a share given to the Church, but the destruction of
monopoly.... No alliance with the University! Away with its books,
inspectors, examinations, certificates, diplomas! All that means the
hand of the State laid on the liberty of the citizen; it is the breath
of incredulity on the younger generation.” Confronted by the violent
rejection of any attempt at reconciliation and threatened interference
with the University on the part of the Church, the Government was trying
to secure to itself the whole teaching fraternity.
The primary schoolmasters groaned under the heavy yoke of the prefects.
“These deep politicians only know how to dismiss.... The rectors will
become the valets of the prefects ...” wrote Pasteur with anger and
distress in a letter dated July, 1850. After the primary schools, the
attacks now reached the colleges. The University was accused of
attending exclusively to Latin verse and Greek translations, and of
neglecting the souls of the students. Romieu, who ironically dubbed the
University “Alma Parens,” and attacked it most bitterly, seemed hardly
fitted for the part of justiciary. He was a former pupil of the Ecole
Polytechnique, who wrote vaudevilles until he was made a prefect by
Louis Philippe. He was celebrated for various tricks which amused Paris
and disconcerted the Government, much to the joy of the Prince de
Joinville,[21] who loved such mystifications. After the fall of Louis
Philippe, Romieu became a totally different personality. He had been
supposed to take nothing seriously; he now put a tragic construction on
everything. He became a prophet of woe, declaring that “gangrene was
devouring the souls of eight year old children.” According to him,
faith, respect, all was being destroyed; he anathematized Instruction
without Education, and stigmatized village schoolmasters as “obscure
apostles” charged with “preaching the doctrines of revolt.” This
violence was partly oratory, but oratory does not minimize violence, it
excites it. Every pamphleteer ends by being a bond-slave to his own
phraseology.
When Romieu appeared in Strasburg as an Envoy Extraordinary entrusted by
the Government with a general inquiry, he found that M. Laurent did not
answer to that ideal of a functionary which was entertained by a
certain party. M. Laurent had the very highest respect for justice; he
distrusted the upstarts whose virtues were very much on the surface; he
never decided on the fate of an inferior without the most painstaking
inquiry; he did not look on an accidental mistake as an unpardonable
fault; he refused to take any immediate and violent measures: all this
caused him to be looked upon with suspicion. “The influence of the
Rector” (thus ran Romieu’s official report) “is hardly, if at all,
noticeable. He should be replaced by a safe man.”
The Minister of Public Instruction, M. de Parieu, had to bow before the
formal wish of the Minister of the Interior, founded upon peremptory
arguments of this kind. M. Laurent was offered the post of Rector at
Châteauroux, a decided step downward. He refused, left Strasburg, and,
with no complaint or recriminations, retired into private life at the
age of fifty-five.
It was when this happy family circle was just about to be enlarged that
its quiet was thus broken into by this untoward result of political
agitation. M. Laurent’s youngest daughter soon after became engaged to
M. Loir, a professor at the Strasburg Pharmaceutical School, who had
been a student at the Ecole Normale, and who ultimately became Dean of
the Faculty of Sciences at Lyons. He was then preparing, assisted by
Pasteur, his “thesis” for the degree of Doctor of Science. In this he
announced some new results based on the simultaneous existence of
hemihedral crystalline forms and the rotatory power. He wrote, “I am
happy to have brought new facts to bear upon the law that M. Pasteur has
enunciated.”
“Why are you not a professor of physics or chemistry!” wrote Pasteur to
Chappuis; “we should work together, and in ten years’ time we would
revolutionize chemistry. There are wonders hidden in crystallization,
and, through it, the inmost construction of substances will one day be
revealed. If you come to Strasburg, you _shall_ become a chemist; I
shall talk to you of nothing but crystals.”
The vacation was always impatiently awaited by Pasteur. He was able to
work more, and to edit the result of his researches in an extract for
the Académie des Sciences. On October 2 his friend received the
following letter: “On Monday I presented this year’s work to the
‘Institut.’ I read a long extract from it, and then gave a vivâ voce
demonstration relative to some crystallographic details. This
demonstration, which I had been specially desired to give, was quite
against the prevailing customs of the Académie. I gave it with my usual
delight in that sort of thing, and it was followed with great attention.
Fortunately for me, the most influential members of the Académie were
present. M. Dumas sat almost facing me. I looked at him several times,
and he expressed by an approving nod of his head that he understood and
was much interested. He asked me to his house the next day, and
congratulated me. He said, amongst other things, that I was a proof that
when a Frenchman took up crystallography he knew what he was about, and
also that if I persevered, as he felt sure I should, I should become the
founder of a school.
“M. Biot, whose kindness to me is beyond all expression, came to me
after my lecture and said, ‘It is as good as it can possibly be.’ On
October 14 he will give his report on my work; he declares I have
discovered a very California. Do not suppose I have done anything
wonderful this year. This is but a satisfactory consequence of preceding
work.”
In his report (postponed until October 28) Biot was more enthusiastic.
He praised the numerous and unforeseen results brought out by Pasteur
within the last two years. “He throws light upon everything he touches,”
he said.
To be praised by Biot was a rare favour; his diatribes were better
known. In a secret committee of the Académie des Sciences (January,
1851) the Académie had to pronounce on the merits of two candidates for
a professorship at the Collège de France: Balard, a professor of the
Faculty of Science, chief lecturer of the Ecole Normale, and Laurent the
chemist, who in order to live had been compelled to accept a situation
as assayer at the Mint. Biot, with his halting step, arrived at the
Committee room and spoke thus: “The title of Member of the Institute is
the highest reward and the greatest honour that a French scientist can
receive, but it does not constitute a privilege of inactivity that need
only be claimed in order to obtain everything.... For several years, M.
Balard has been in possession of two large laboratories where he might
have executed any work dictated to him by his zeal, whilst nearly all M.
Laurent’s results have been effected by his unaided personal efforts at
the cost of heavy sacrifices. If you give the college vacancy to M.
Balard, you will add nothing to the opportunities for study which he
already has; but it will take away from M. Laurent the means of work
that he lacks and that we have now the opportunity of providing for him.
The chemical section, and indeed the whole Academy will easily judge on
which side are scientific justice and the interests of future progress.”
Biot had this little speech printed and sent a copy of it to Pasteur.
The incident led to a warm dispute, and Biot lost his cause. Pasteur
wrote to Chappuis, “M. Biot has done everything that was possible to do
in order that M. Laurent should win, and the final result is a great
grief to him. But really,” the younger man added, more indulgent than
the old man, and divided between his wishes for Laurent and the fear of
the sorrow Balard would have felt, “M. Balard would not have deserved so
much misfortune. Think of the disgrace it would have been to him if
there had been a second vote favourable to Laurent, especially coming
from the Institute of which he is a member.” At the end of that
campaign, Biot in a fit of misanthropy which excepted Pasteur alone, and
knowing that Pasteur had spoken with effusion of their mutual feelings,
wrote to him as follows: “I am touched by your acknowledgment of my deep
and sincere affection for you, and I thank you for it. But whilst
keeping your attachment for me as I preserve mine for you, let me for
the future rejoice in it in the secret recesses of my heart and of
yours. The world is jealous of friendships however disinterested, and my
affection for you is such that I wish people to feel that they honour
themselves by appreciating you, rather than that they should know that
you love me and that I love you. Farewell. Persevere in your good
feelings as in your splendid career, and be happy. Your friend.”
The character of Biot, a puzzle to Sainte Beuve, seems easier to
understand after reading those letters, written in a small conscientious
hand. The great critic wrote: “Who will give us the secret key to Biot’s
complex nature, to the curiosities, aptitudes, envies, prejudices,
sympathies, antipathies, folds and creases of every kind in his
character?” Even with no other documents, the history of his relations
with Pasteur would throw light upon this nature, not so “complex” after
all. From the day when Pasteur worked out his first experiment before
Biot, at first suspicious, then astonished and finally touched to the
heart, until the period of absolute mutual confidence and friendship, we
see rising before us the image of this true scientist, with his rare
independence, his good-will towards laborious men and his mercilessness
to every man who, loving not Science for its own sake, looked upon a
discovery as a road to fortune, pecuniary or political.
He loved both science and letters, and, now that age had bent his tall
form, instead of becoming absorbed in his own recollections and the
contemplation of his own labours, he kept his mind open, happy to learn
more every day and to anticipate the future of Pasteur.
During the vacation of 1851 Pasteur came to Paris to bring Biot the
results of new researches on aspartic and malic acids, and he desired
his father to join him in order to efface the sad impression left by his
former journey in 1838. Biot and his wife welcomed the father and son as
they would have welcomed very few friends. Touched by so much kindness,
Joseph Pasteur on his return in June wrote Biot a letter full of
gratitude, venturing at the same time to send the only thing it was in
his power to offer, a basket of fruit from his garden. Biot answered as
follows: “Sir, my wife and I very much appreciate the kind expressions
in the letter you have done me the honour of writing me. Our welcome to
you was indeed as hearty as it was sincere, for I assure you that we
could not see without the deepest interest such a good and honourable
father sitting at our modest table with so good and distinguished a son.
I have never had occasion to show that excellent young man any feelings
but those of esteem founded on his merit, and an affection inspired by
his personality. It is the greatest pleasure that I can experience in my
old age, to see young men of talent working industriously and trying to
progress in a scientific career by means of steady and persevering
labour, and not by wretched intriguing. That is what has made your son
dear to me, and his affection for me adds yet to his other claims and
increases that which I feel for him. We are therefore even with one
another. As to your kindness in wishing that I should taste fruit from
your garden, I am very grateful for it, and I accept it as cordially as
you send it.”
Pasteur had also brought Biot some other products--a case full of new
crystals. Starting from the external configuration of crystals, he
penetrated the individual constitution of their molecular groups, and
from this point of departure, he then had recourse to the resources of
chemistry and optics. Biot never ceased to admire the sagacity of the
young experimentalist who had turned what had until then been a mere
crystallographic character into an element of chemical research.
Equally interested by the general consequences of these studies, so
delicate and so precise, M. de Senarmont wished in his turn to examine
the crystals. No one approved more fully than he the expressions of the
old scientist, who ended in this way his 1851 report: “If M. Pasteur
persists in the road he has opened, it may be predicted of him that what
he has found is nothing to what he will find.” And, delighted to see the
important position that Pasteur was taking at Strasburg and the
unexpected extension of crystallography, Biot wrote to him: “I have read
with much interest the thesis of your brother-in-law, M. Loir. It is
well conceived and well written, and he establishes with clearness many
very curious facts. M. de Senarmont has also read it with very great
pleasure, and I beg you will transmit our united congratulations to your
brother-in-law.” Biot added, mixing as he was wont family details with
scientific ideas: “We highly appreciated your father, the rectitude of
his judgment, his firm, calm, simple reason and the enlightened love he
bears you.”
“My plan of study is traced for this coming year,” wrote Pasteur to
Chappuis at the end of December. “I am hoping to develop it shortly in
the most successful manner.... I think I have already told you that I am
on the verge of mysteries, and that the veil which covers them is
getting thinner and thinner. The nights seem to me too long, yet I do
not complain, for I prepare my lectures easily, and often have five
whole days a week that I can give up to the laboratory. I am often
scolded by Mme. Pasteur, but I console her by telling her that I shall
lead her to fame.”
He already foresaw the greatness of his work. However he dare not speak
of it, and kept his secret, save with the confidante who was now a
collaborator, ever ready to act as secretary, watching over the precious
health of which he himself took no account, an admirable helpmeet, to
whom might be applied the Roman definition, _socia rei humanæ atque
divinæ_. Never did life shower more affection upon a man. Everything at
that time smiled upon him. Two fair children in the home, great security
in his work, no enemies, and the comfort of receiving the approval and
counsel of masters who inspired him with a feeling of veneration.
“At my age,” wrote Biot to Pasteur, “one lives only in the interest one
takes in those one loves. You are one of the small number who can
provide such food for my mind.” And alluding in that same letter
(December 22, 1851) to four reports successively approved of by Balard,
Dumas, Regnault, Chevreul, Senarmont and Thenard: “I was very happy to
see, in those successive announcements of ideas of so new and so
far-reaching a nature, that you have said--and that we have made you
say--nothing that should now be contradicted or objected to in one
single point. I still have in my hands the pages of your last paper
concerning the optical study of malic acid. I have not yet returned them
to you, as I wish to extract from them some results that I shall place
to your credit in a paper I am now writing.”
It was no longer Biot and Senarmont only who were watching the growing
importance of Pasteur’s work. At the beginning of the year 1852 the
physicist Regnault thought of making Pasteur a corresponding member of
the Institute. Pasteur was still under thirty. There was a vacancy in
the General Physics section, why not offer it to him? said Regnault,
with his usual kindliness. Biot shook his head: “It is to the Chemistry
section that he ought to belong.” And, with the courage of sincere
affection, he wrote to Pasteur, “Your work marks your place in chemistry
rather than physics, for in chemistry you are in the front rank of
inventors, whilst in physics you have applied processes already known
rather than invented new ones. Do not listen to people, who, without
knowing the ground, would cause you to desire, and even to hastily
obtain, a distinction which would be above your real and recognized
claims.... Besides, you can see for yourself how much your work of the
last four years has raised you in every one’s estimation. And that
place, which you have made for yourself in the general esteem, has the
advantage of not being subject to the fluctuations of the ballot.
Farewell, dear friend, write to me when you have time, and be assured
that my interest in hard workers is about the only thing which yet makes
me wish to live. Your friend.”
Pasteur gratefully accepted these wise counsels. In an excess of
modesty, he wrote to Dumas that he should not apply as candidate even
if a place for a correspondent were vacant in the Chemistry section. “Do
you then believe,” answered Dumas with a vivacity very unlike his usual
solemn calmness, “do you believe that we are insensible to the glory
which your work reflects on French chemistry, and on the Ecole from
whence you come? The very day I entered the Ministry, I asked for the
Cross[22] for you. I should have had in giving it to you myself a
satisfaction which you cannot conceive. I don’t know whence the delay
and difficulty arise. But what I do know is that you make my blood boil
when you speak in your letter of the necessity of leaving a free place
in chemistry to the men you mention, one or two excepted.... What
opinion have you then of our judgment? When there _is_ a vacant place,
you shall be presented, supported and elected. It is a question of
justice and of the great interests of science: we shall make them
prevail.... When the day comes, there will be means found to do what is
required for the interests of science, of which you are one of the
firmest pillars, and one of the most glorious hopes. Heartily yours.”
“My dear father,” wrote Pasteur, sending his father a copy of this
letter, “I hope you will be proud of M. Dumas’ letter. It surprised me
very much. I did not believe that my work deserved such a splendid
testimony, though I recognize its great importance.”
Thus were associated in Pasteur the full consciousness of his great
mental power with an extreme ingenuousness. Instead of the pride and
egotism provoked, almost excusably, in so many superior men by excessive
strength, his character presented the noblest delicacy.
Another arrangement occurred to Regnault: that he himself should accept
the direction of the Sèvres Manufactory, and give up to Pasteur his
professorship at the Ecole Polytechnique. Others suggested that Pasteur
should become chief lecturer at the Ecole Normale. Rumours of these
possibilities reached Strasburg, but Pasteur’s thoughts were otherwise
absorbed. He was concerned with the manner in which he could modify the
crystalline forms of certain substances which, though optically active,
did not at the first view present the hemihedral character, and with the
possibility of provoking the significant faces by varying the nature of
the dissolving agents. Biot was anxious that he should not be disturbed
in these ingenious researches, and advised him to remain at Strasburg in
terms as vigorous as any of his previous advice. “As to the accidents
which come from or depend on men’s caprice, be strong-minded enough to
disdain them yet awhile. Do not trouble about anything, but pursue
indefatigably your great career. You will be rewarded in the end, the
more certainly and unquestionably that you will have deserved it more
fully. The time is not far when those who can serve you efficiently will
feel as much pride in doing so as shame and embarrassment in not having
done so already.”
When Pasteur came to Paris in August, for what he might have called his
annual pilgrimage, Biot had reserved for him a most agreeable surprise.
Mitscherlich was in Paris, where he had come, accompanied by another
German crystallographer, G. Rose, to thank the Académie for appointing
him a foreign Associate. They both expressed a desire to see Pasteur,
who was staying in a hotel in the Rue de Tournon. Biot, starting for his
daily walk round the Luxembourg Garden, left this note: “Please come to
my house to-morrow at 8 a.m., if possible with your products. M.
Mitscherlich and M. Rose are coming at 9 to see them.” The interview was
lengthy and cordial. In a letter to his father--who now knew a great
deal about crystals and their forms, thanks to Pasteur’s lucid
explanations--we find these words. “I spent two and a half hours with
them on Sunday at the Collège de France, showing them my crystals. They
were much pleased, and highly praised my work. I dined with them on
Tuesday at M. Thenard’s; you will like to see the names of the guests:
Messrs. Mitscherlich, Rose, Dumas, Chevreul, Regnault, Pelouze, Péligot,
C. Prévost, and Bussy. You see I was the only outsider, they are all
members of the Académie.... But the chief advantage of my meeting these
gentlemen is that I have heard from them the important fact that there
is a manufacturer in Germany who again produces some racemic acid. I
intend to go and see him and his products, so as to study thoroughly
that singular substance.”
At the time when scientific novels were in fashion, a whole chapter
might have been written on Pasteur in search of that acid. In order to
understand in a measure his emotion on learning that a manufacturer in
Saxony possessed this mysterious acid, we must remember that the racemic
acid--produced for the first time by Kestner at Thann in 1820, through
a mere accident in the manufacture of tartaric acid--had suddenly ceased
to appear, in spite of all efforts to obtain it again. What then was the
origin of it?
Mitscherlich believed that the tartars employed by this Saxony
manufacturer came from Trieste. “I shall go to Trieste,” said Pasteur;
“I shall go to the end of the world. I _must_ discover the source of
racemic acid, I must follow up the tartars to their origin.” Was the
acid existent in crude tartars, such as Kestner received in 1820 from
Naples, Sicily, or Oporto? This was all the more probable from the fact
that from the day when Kestner began to use semi-refined tartars he had
no longer found any racemic acid. Should one conclude that it remained
stored up in the mother-liquor?
With a feverish impetuosity that nothing could soothe, Pasteur begged
Biot and Dumas to obtain for him a mission from the Ministry or the
Académie. Exasperated by red tape delays, he was on the point of writing
directly to the President of the Republic. “It is a question,” he said,
“that France should make it a point of honour to solve through one of
her children.” Biot endeavoured to moderate this excessive impatience.
“It is not necessary to set the Government in motion for this,” he said,
a little quizzically. “The Academy, when informed of your motives might
very well contribute a few thousand francs towards researches on the
racemic acid.” But when Mitscherlich gave Pasteur a letter of
recommendation to the Saxony manufacturer, whose name was Fikentscher
and who lived near Leipzig, Pasteur could contain himself no longer, and
went off, waiting for nothing and listening to no one. His travelling
impressions were of a peculiar nature. We will extract passages from a
sort of diary addressed to Madame Pasteur so that she might share the
emotions of this pursuit. He starts his campaign on the 12th September.
“I do not stop at Leipzig, but go on to Zwischau, and then to M.
Fikentscher. I leave him at nightfall and go back to him the next
morning very early. I have spent all to-day, Sunday, with him. M.
Fikentscher is a very clever man, and he has shown me his whole
manufactory in every detail, keeping no secrets from me.... His factory
is most prosperous. It comprises a group of houses which, from a
distance, and situated on a height as they are, look almost like a
little village. It is surrounded by 20 hectares[23] of well cultivated
ground. All this is the result of a few years’ work. As to _the_
question, here is a little information that you will keep strictly to
yourself for the present. M. Fikentscher obtained racemic acid for the
first time about twenty-two years ago. He prepared at that time rather a
large quantity. Since then only a very small amount has been formed in
the process of manufacture and he has not troubled to preserve it. When
he used to obtain most, his tartars came from Trieste. This confirms,
though not in every point, what I heard from M. Mitscherlich. Anyhow,
here is my plan: Having no laboratory at Zwischau, I have just returned
to Leipzig with two kinds of tartars that M. Fikentscher now uses, some
of which come from Austria, and some from Italy. M. Fikentscher has
assured me that I should be very well received here by divers
professors, who know my name very well, he says. To-morrow Monday
morning, I will go to the Université and set up in some laboratory or
other. I think that in five or six days I shall have finished my
examination of these tartars. Then I shall start for Vienna, where I
shall stay two or three days and rapidly study Hungarian tartars....
Finally I shall go to Trieste, where I shall find tartars of divers
countries, notably those of the Levant, and those of the neighbourhood
of Trieste itself. On arriving here at M. Fikentscher’s I have
unfortunately discovered a very regrettable circumstance. It is that the
tartars he uses have already been through one process in the country
from which they are exported, and this process is such that it evidently
eliminates and loses the greater part of the racemic acid. At least I
think so. I must therefore go to the place itself. If I had enough money
I should go on to Italy; but that is impossible, it will be for next
year. I shall give ten years to it if necessary; but it will not be, and
I am sure that in my very next letter I shall be able to tell you that I
have some good results. For instance, I am almost sure to find a prompt
means of testing tartars from the point of view of racemic acid. That is
a point of primary importance for my work. I want to go quickly through
examining all these different tartars; that will be my first study....
M. Fikentscher will take nothing for his products. It is true that I
have given him hints and some of my own enthusiasm. He wants to prepare
for commercial purposes some _left_ tartaric acid, and I have given him
all the necessary crystallographic indications. I have no doubt he will
succeed.”
_Leipzig, Wednesday, September 15, 1852._ “My dear Marie, I do not want
to wait until I have the results of my researches before writing to you
again. And yet I have nothing to tell you, for I have not left the
laboratory for three days, and I know nothing of Leipzig but the street
which goes from the Hôtel de Bavière to the Université. I come home at
dusk, dine, and go to bed. I have only received, in M. Erdmann’s study,
the visit of Professor Hankel, professor of physics of the Leipzig
Université, who has translated all my treatises in a German paper edited
by M. Erdmann. He has also studied hemihedral crystals, and I enjoyed
talking with him. I shall also soon meet the professor of mineralogy, M.
Naumann.
“To-morrow only shall I have a first result concerning racemic acid. I
shall stay about ten days longer in Leipzig. It is more than I told you,
and the reason lies in rather a happy circumstance. M. Fikentscher has
kindly written to me and to a firm in Leipzig, and I heard yesterday
from the head of that firm that, very likely, they can get me to-morrow
some tartars absolutely crude and of the same origin as M.
Fikentscher’s. The same gentleman has given me some information about a
factory at Venice, and will give me a letter of recommendation to a firm
in that city, also for Trieste. In this way the journey I proposed to
make in that town will not simply be a pleasure trip.... I shall write
to M. Biot as soon as I have important results. To-day has been a good
day, and in about three or four more you will no doubt receive a
satisfactory letter.”
_Leipzig, September 18, 1852._ “My dear Marie, the very question which
has brought me here is surrounded with very great difficulties.... I
have only studied one tartar thoroughly since I have been here; it comes
from Naples and has been refined once. It contains racemic acid, but in
such infinitesimal proportions that it can only be detected by the most
delicate process. It is only by manufacture on a very large scale that a
certain quantity could be prepared. But I must tell you that the first
operation undergone by this tartar must have deprived it almost entirely
of racemic acid. Fortunately M. Fikentscher is a most enlightened man,
he perfectly understands the importance of this acid and he is prepared
to follow most minutely the indications that I shall give him in order
to obtain this singular substance in quantities such that it can again
be easily turned into commercial use. I can already conceive the history
of this product. M. Kestner must have had at his disposal in 1820 some
Neapolitan tartars, as indeed he said he had, and he must have operated
on crude tartar. That is the whole secret.... But is it certain that
almost the whole of the acid is lost in the first manufacture undergone
by tartar? I believe it is. But it must be proved. There are at Trieste
and at Venice two tartar refineries of which I have the addresses. I
also have letters of introduction. I shall examine there (if I find a
laboratory) the residual products, and I shall make minute inquiries
respecting the places the tartars used in those two cities come from.
Finally, I shall procure a few kilogrammes, which I shall carefully
study when I get back to France....”
_Freiberg, September 23, 1852._ “I arrived on the evening of the 21st at
Dresden, and I had to wait until eleven the next morning to have my
passport _visé_, so I could not start for Freiberg before seven p.m. I
took advantage of that day to visit the capital of Saxony, and I can
assure you that I saw some admirable things. There is a most beautiful
museum containing pictures by the first masters of every school. I spent
over four hours in the galleries, noting on my catalogue the pictures I
most enjoyed. Those I liked I marked with a cross; but I soon put two,
three crosses, according to the degree of my enthusiasm. I even went as
far as four.
“I also visited what they call the green vault room, an absolutely
unique collection of works of art, gems, jewels ... then some churches,
avenues, admirable bridges across the Elbe....
“I then started for Freiberg at 7.... My love of crystals took me first
to the learned Professor of mineralogy, Breithaupt, who received me as
one would not be received in France. After a short colloquy, he passed
into the next room, came back in a black tail-coat with three little
decorations in his button hole, and told me he would first present me to
the Baron von Beust, Superintendent of Factories, so as to obtain a
permit to visit the latter.... Then he took me for a walk, talking
crystals the whole time....”
P.S.--“Mind you tell M. Biot how I was received; it will please him.”
_Vienna, September 27, 1852._ “Yesterday, Monday morning, I set out to
call upon several people. Unfortunately, I hear that Professor Schrotten
is at Wiesbaden, at a scientific congress, as well as M. Seybel, a
manufacturer of tartaric acid. M. Miller, a merchant for whom I had a
letter of recommendation, was kind enough to ask M. Seybel’s business
manager for permission for me to visit the factory in his absence. He
refused, saying he was not authorized. But I did not give in; I asked
for the addresses of Viennese professors, and I fortunately came upon
that of a very well known scientific man, M. Redtenbacher, who has been
kind to me beyond all description. At 6 a.m. he came to my hotel, and we
took the train at 7 for the Seybel manufactory, which is at a little
distance from Vienna. We were received by the chemist of the factory,
who made not the slightest difficulty in introducing us into the
sanctuary, and after many questions we ended by being convinced that the
famous racemic acid was seen there last winter.... I reserve for later
many details of great interest, for here they have operated for years on
crude tartar. I came away very happy.
“There is another factory of tartaric acid in Vienna. We go there; I
repeat through M. Redtenbacher my string of questions. They have seen
nothing. I ask to see their products, and I come upon a barrel full of
tartaric acid crystals, on the surface of which I think I perceive _the_
substance. A first test made with dirty old glasses then and there
confirms my doubts; they become a certainty a few moments later at M.
Redtenbacher’s laboratory. We dine together; then we go back to the
factory, where we learn, miraculous to relate, that they are just now
embarrassed in their manufacturing process, and, almost certainly, the
product which hinders them--though it is in a very small quantity, and
they take it for sulphate of potash--is no other than racemic acid. I
wish I could give you more details of this eventful day. I was to have
left Vienna to-day, but, as you will understand, I shall stay until I
have unravelled this question. I have already in the laboratory three
kinds of products from the factory. To-morrow night, or the day after, I
shall know what to think....
“You remember what I used to say to you and to M. Dumas, that almost
certainly the first operation which tartar goes through in certain
factories causes it to lose all or nearly all its racemic acid. Well, in
the two Viennese factories, it is only two years since they began to
operate on crude tartar, and it is only two years since they first saw
the supposed sulphate of potash, the supposed sulphate of magnesia. For,
at M. Seybel’s, they had taken for sulphate of magnesia the little
crystals of racemic acid.
“Shortly, this is as far as I have come--I spare you many details:--
1. “The Naples tartar contains racemic acid.
2. “The Austrian tartar (neighbourhood of Vienna) contains racemic acid.
3. “The tartars of Hungary, Croatia, Carniola contain racemic acid.
4. “The tartar of Naples contains notably more than the latter, for it
presents racemic acid even after one refining process, whilst that from
Austria and Hungary only presents it when in the crude state.
“I believe it now to be extremely probable that I shall find some
racemic acid in French tartars, but in very small quantities; and if it
is not detected it is because all the circumstances of the manufacture
of tartaric acid are unknown or unappreciated, or because some little
precaution is neglected that would preserve it or make it visible.
“You see, dear Marie, how useful was my journey.”
“_Vienna, September 30, 1852._ I am not going to Trieste; I shall start
for Prague this evening.”
“_Prague, October 1, 1852._ Here is a startling piece of news. I arrive
in Prague; I settle down in the Hôtel d’Angleterre, have lunch, and call
on M. Rochleder, Professor of chemistry, so that he may introduce me to
the manufacturer. I go to the chemist of the factory, Dr. Rassmann, for
whom I had a letter from M. Redtenbacher, his former master. That letter
contained all the questions that I usually make to the manufacturers of
tartaric acid.
“Dr. Rassmann hardly took time to read the letter; he saw what it dealt
with, and said to me: ‘I have long obtained racemic acid. The Paris
Pharmaceutical Society offered a prize for whoever manufactured it. It
is a product of manufacture; I obtain it with the assistance of tartaric
acid.’ I took the chemist’s hand affectionately, and made him repeat
what he had said. Then I added: ‘You have made one of the greatest
discoveries that it is possible to make in chemistry. Perhaps you do not
realise as I do the full importance of it. But allow me to tell you
that, with my ideas, I look upon that discovery as impossible. I do not
ask for your secret; I shall await the publication of it with the
greatest impatience. So that is really true? You take a kilogramme of
pure tartaric acid, and with that you make racemic acid?’
“‘Yes,’ he said; ‘but it is still’ ... and as he had some difficulty in
expressing himself, I said: ‘It is still surrounded with great
difficulties?’
“‘Yes, monsieur.’
“Great heavens! what a discovery! if he had really done what he says!
But no; it is impossible. There is an abyss to cross, and chemistry is
yet too young.”
_Second letter, same date._ “M. Rassmann is mistaken.... He has never
obtained racemic acid with pure tartaric acid. He does what M.
Fikentscher and the Viennese manufacturers do, with slight differences,
which confirm the general opinion I expressed in my letter to M. Dumas a
few days ago.”
That letter, and also another addressed to Biot, indicated that racemic
acid was formed in varying quantities in the mother-liquor, which
remained after the purification of crude tartars.
“I can at last,” Pasteur wrote from Leipzig to his wife, “turn my steps
again towards France. I want it; I am very weary.”
In an account of this journey in a newspaper called _La Vérité_ there
was this sentence, which amused everybody, Pasteur included: “Never was
treasure sought, never adored beauty pursued over hill and vale with
greater ardour.”
But the hero of scientific adventures was not satisfied. He had foreseen
by the examination of crystalline forms, the correlation between
hemihedral dissymmetry and rotatory power; this was, to his mind, a
happy foresight. He had afterwards succeeded in separating the racemic
acid, inactive on polarized light, into two acids, left and right,
endowed with equal but contrary rotatory powers; this was a discovery
deservedly qualified as memorable by good judges in those matters. Now
he had indicated the mother-liquor as a source of racemic acid, and this
was a precious observation that Kestner, who was specially interested in
the question, confirmed in a letter to the Académie des Sciences
(December, 1852), sending at the same time three large phials of racemic
acid, one of which, made of thin glass, broke in Biot’s hands. But a
great advance, apparently unrealizable, remained yet to be accomplished.
Could not racemic acid be produced by the aid of tartaric acid?
Pasteur himself, as he told the optimist Rassmann, did not believe such
a transformation possible. But, by dint of ingenious patience, of
trials, of efforts of all sorts, he fancied he was nearing the goal. He
wrote to his father: “I am thinking of one thing only, of the hope of a
brilliant discovery which seems not very far. But the result I foresee
is so extraordinary that I dare not believe it.” He told Biot and
Senarmont of this hope. Both seemed to doubt. “I advise you,” wrote
Senarmont, “not to speak until you can say: ‘I obtain racemic acid
artificially with some tartaric acid, of which I have myself verified
the purity; the artificial acid, like the natural, divides itself into
equal equivalents of left and right tartaric acids, and those acids have
the forms, the optical properties, all the chemical properties of those
obtained from the natural acid.’ Do not believe that I want to worry
you; the scruples I have for you I should have for myself; it is well to
be doubly sure when dealing with such a fact.” But with Biot, Senarmont
was less reserved; he believed the thing done. He said so to Biot, who,
prudent and cautious, still desirous of warning Pasteur, wrote to him on
May 27, 1853, speaking of Senarmont: “The affection with which your
work, your perseverance and your moral character have inspired him makes
him desire impossible prodigies for you. My friendship for you is less
hastily hopeful and harder to convince. However, enjoy his friendship
fully, and be as unreserved with him as you are with me. You can do so
in full security; I do not know a stronger character than his. I have
said and repeated to him how happy I am to see the affection he bears
you. For there will be at least one man who will love you and understand
you when I am gone. Farewell; enough sermons for to-day; a man must be
as I am, in his eightieth year, to write such long homilies. Fortunately
you are accustomed to mine, and do not mind them.”
At last, on the first of June, here is the letter announcing the great
fact: “My dear father, I have just sent out the following telegram:
_Monsieur Biot, Collège de France, Paris. I transform tartaric acid into
racemic acid; please inform MM. Dumas and Senarmont._ Here is at last
that racemic acid (which I went to seek at Vienna) artificially obtained
through tartaric acid. I long believed that that transformation was
impossible. This discovery will have incalculable consequences.”
“I congratulate you,” answered Biot on the second of June. “Your
discovery is now complete. M. de Senarmont will be as delighted as I am.
Please congratulate also Mme. Pasteur from me; she must be as pleased as
you.” It was by maintaining tartrate of cinchonin at a high temperature
for several hours that Pasteur had succeeded in transforming tartaric
acid into racemic acid. Without entering here into technical details
(which are to be found in a report of the Paris Pharmaceutical Society,
concerning the prize accorded to Pasteur for the artificial production
of racemic acid) it may be added that he had also produced the neutral
tartaric acid--that is: with no action on polarized light--which
appeared at the expense of racemic acid already formed. There were
henceforth four different tartaric acids:--(1) the right or
dextro-tartaric acid; (2) the left or lævo-tartaric acid; (3) the
combination of the right and the left or racemic acid; and (4) the
meso-tartaric acid, optically inactive.
The reports of the Académie des Sciences also contain accounts of
occasional discoveries, of researches of all kinds accessory to the
history of racemic acid. Thus aspartic acid had caused Pasteur to make a
sudden journey from Strasburg to Vendôme. A chemist named
Dessaignes--who was municipal receiver of that town, and who found time
through sheer love of science for researches on the constitution of
divers substances--had announced a fact which Pasteur wished to verify;
it turned out to be inaccurate.
One whole sitting of the Académie, the third of January, 1853, was given
up to Pasteur’s name and growing achievements.
After all this Pasteur came back to Arbois with the red ribbon of the
Legion of Honour. He had not won it in the same way as his father had,
but he deserved it as fully. Joseph Pasteur, delighting in his
illustrious son, wrote effusively to Biot; indeed the old scientist had
had his share in this act of justice. Biot answered in the following
letter, which is a further revelation of his high and independent ideal
of a scientific career.
“Monsieur, your good heart makes out my share to be greater than it is.
The splendid discoveries made by your worthy and excellent son, his
devotion to science, his indefatigable perseverance, the conscientious
care with which he fulfils the duties of his situation, all this had
made his position such that there was no need to solicit for him what he
had so long deserved. But one might boldly point out that it would be a
real loss to the Order if he were not promptly included within its
ranks. That is what I did, and I am very glad to see that the too long
delay is now at an end. I wished for this all the more as I knew of your
affectionate desire that this act of justice should be done. Allow me to
add, however, that in our profession our real distinction depends on us
alone, fortunately, and not on the favour or indifference of a minister.
In the position that your son has acquired, his reputation will grow
with his work, no other help being needed; and the esteem he already
enjoys, and which will grow day by day, will be accorded to him, without
gainsaying or appeal, by the Grand Jury of scientists of all nations--an
absolutely just tribunal, the only one we recognize.
“Allow me to add to my congratulations the expression of the esteem and
cordial affection with which you have inspired me.”
On his return to Strasburg Pasteur went to live in a house in the Rue
des Couples, which suited him as being near the Académie and his
laboratory; it also had a garden where his children could play. He was
full of projects, and what he called the “spirit of invention” daily
suggested some new undertaking. The neighbourhood of Germany, at that
time a veritable hive of busy bees, was a fertile stimulant to the
French Faculty at Strasburg.
But material means were lacking. When Pasteur received the prize of
1,500 francs given him by the Pharmaceutical Society, he gave up half of
it to buying instruments which the Strasburg laboratory was too poor to
afford. The resources then placed by the State at his disposal by way of
contribution to the expenses of a chemistry class only consisted of
1,200 francs under the heading “class expenses.” Pasteur had to pay the
wages of his laboratory attendant out of it. Now that he was better
provided, thanks to his prize, he renewed his studies on crystals.
Taking up an octahedral crystal, he broke off a piece of it, then
replaced it in its mother-liquor. Whilst the crystal was growing larger
in every direction by a deposit of crystalline particles, a very active
formation was taking place on the mutilated part; after a few hours the
crystal had again assumed its original shape. The healing up of wounds,
said Pasteur, might be compared to that physical phenomenon. Claude
Bernard, much struck later on by these experiments of Pasteur’s and
recalling them with much praise, said in his turn--
“These reconstituting phenomena of crystalline redintegration afford a
complete comparison with those presented by living beings in the case of
a wound more or less deep. In the crystal as in the animal, the damaged
part heals, gradually taking back its original shape, and in both cases
the reformation of tissue is far more active in that particular part
than under ordinary evolutive conditions.”
Thus those two great minds saw affinities hidden under facts apparently
far apart. Other similarities yet more unexpected carried Pasteur away
towards the highest region of speculation. He spoke with enthusiasm of
molecular dissymmetry; he saw it everywhere in the universe. These
studies in dissymmetry gave birth twenty years later to a new science
arising immediately out of his work, viz. stereo-chemistry, or the
chemistry of space. He also saw in molecular dissymmetry the influence
of a great cosmic cause--
“The universe,” he said one day, “is a dissymmetrical whole. I am
inclined to think that life, as manifested to us, must be a function of
the dissymmetry of the universe and of the consequences it produces. The
universe is dissymmetrical; for, if the whole of the bodies which
compose the solar system were placed before a glass moving with their
individual movements, the image in the glass could not be superposed to
the reality. Even the movement of solar life is dissymmetrical. A
luminous ray never strikes in a straight line the leaf where vegetable
life creates organic matter. Terrestrial magnetism, the opposition which
exists between the north and south poles in a magnet, that offered us by
the two electricities positive and negative, are but resultants from
dissymmetrical actions and movements.”
“Life,” he said again, “is dominated by dissymmetrical actions. I can
even foresee that all living species are primordially, in their
structure, in their external forms, functions of cosmic dissymmetry.”
And there appeared to him to be a barrier between mineral or artificial
products and products formed under the influence of life. But he did
not look upon it as an impassable one, and he was careful to say, “It is
a distinction of fact and not of absolute principle.” As nature
elaborates immediate principles of life by means of dissymmetrical
forces, he wished that the chemist should imitate nature, and that,
breaking with methods founded upon the exclusive use of symmetrical
forces, he should bring dissymmetrical forces to bear upon the
production of chemical phenomena. He himself, after using powerful
magnets to attempt to introduce a manifestation of dissymmetry into the
form of crystals, had had a strong clockwork movement constructed, the
object of which was to keep a plant in continual rotatory motion first
in one direction then in another. He also proposed to try to keep a
plant alive, from its germination under the influence of solar rays
reversed by means of a mirror directed by a heliostat.
But Biot wrote to him: “I should like to be able to turn you from the
attempts you wish to make on the influence of magnetism on vegetation.
M. de Senarmont agrees with me. To begin with, you will spend a great
deal on the purchase of instruments with the use of which you are not
familiar, and of which the success is very doubtful. They will take you
away from the fruitful course of experimental researches which you have
followed hitherto, where there is yet so much for you to do, and will
lead you from the certain to the uncertain.”
“Louis is rather too preoccupied with his experiments,” wrote Mme.
Pasteur to her father-in-law; “you know that those he is undertaking
this year will give us, if they succeed, a Newton or a Galileo.”
But success did not come. “My studies are going rather badly,” wrote
Pasteur in his turn (December 30). “I am almost afraid of failing in all
my endeavours this year, and of having no important achievement to
record by the end of next year. I am still hoping, though I suppose it
was rather mad to undertake what I have undertaken.”
Whilst he was thus struggling, an experiment, which for others would
have been a mere chemical curiosity, interested him passionately.
Recalling one day how his first researches had led him to the study of
ferments: “If I place,” he said, “one of the salts of racemic acid,
paratartrate or racemate of ammonia, for instance, in the ordinary
conditions of fermentation, the dextro-tartaric acid alone ferments, the
other remains in the liquor. I may say, in passing, that this is the
best means of preparing lævo-tartaric acid. Why does the
dextro-tartaric acid alone become putrefied? Because the ferments of
that fermentation feed more easily on the right than on the left
molecules.”
“I have done yet more,” he said much later, in a last lecture to the
Chemical Society of Paris; “I have kept alive some little seeds of
_penicillium glaucum_--that mucor which is to be found everywhere--on
the surface of ashes and paratartaric acid and I have seen the
lævo-tartaric acid appear....”
What seemed to him startling in those two experiments was to find
molecular dissymmetry appear as a modifying agent on chemical affinities
in a phenomenon of the physiological order.
By an interesting coincidence it was at the very moment when his studies
were bringing him towards fermentations that he was called to a country
where the local industry was to be the strongest stimulant to his new
researches.