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 viv 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.