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  Now that people of the East of France had been shown how to keep their wine from going bad, the people of the middle of France clamored for Pasteur to come and save their vinegar-making industry. So he rushed down to Tours. He had got used to looking for microscopic beings in all kinds of things by now—he no longer groped as he had had to do at first; he approached the vinegar kegs, where wine was turning itself into vinegar, he saw a peculiar-looking scum on the surface of the liquor in the barrels. “That scum has to be there, otherwise we get no vinegar,” explained the manufacturers. In a few weeks of swift, sure-fingered investigation that astonished the vinegar-makers and their wives, Pasteur found that the scum on the kegs was nothing more nor less than billions upon billions of microscopic creatures. He took off great sheets of this scum and tested it and weighed it and fussed with it, and at last he told an audience of vinegar-makers and their wives and families that the microbes which change wine to vinegar actually eat up and turn into vinegar ten thousand times their own weight of alcohol in a few days. What gigantic things these infinitely tiny beings can do—think of a man of two hundred pounds chopping two millions of pounds of wood in four days! It was by some such homely comparison as this one that he made microbes part of these humble people's lives, it was so that he made them respect these miserably small creatures; it was by pondering on their fiendish capacity for work that Pasteur himself got used to the idea that there was nothing so strange about a tiny beast, no larger than the microbe of vinegar, getting into an ox or an elephant or a man—and doing him to death. Before he left them he showed the people of Tours how to cultivate and care for those useful wee creatures that so strangely added oxygen to wine to turn it into vinegar—and millions of francs for them.

  These successes made Pasteur drunk with confidence in his method of experiment; he began to dream impossible gaudy dreams—of immense discoveries and super-Napoleonic microbe huntings—and he did more than brood alone over these dreams; he put them into speeches and preached them. He became, in a word, a new John the Baptist of the religion of the Germ Theory, but unlike the unlucky Baptist, Pasteur was a forerunner who lived to see at least some of his prophecies come true.

  Then for a short time he worked quietly in his laboratory in Paris—there was nothing for him to save just then—until one day in 1865 Fate came to his door and knocked. Fate in the guise of his old professor, Dumas, called on him and asked him to change himself from a man of science into a silkworm doctor. “What's wrong with silkworms? I did not know that they ever had diseases—I know nothing at all about silkworms—what's more, I have never even seen one!” protested Pasteur.

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  “The silk country of the South is my native country,” answered Dumas. “I've just come back from there—it is terrible—I cannot sleep nights for thinking of it, my poor country, my village of Alais. . . This country that used to be rich, that used to be gay with mulberry trees which my people used to call the Golden Tree—this country is desolate now. The lovely terraces are going to ruin—the people, they are my people, they are starving. . . ” Tears were in his voice.

  Anything but a respecter of persons, Pasteur who loved and respected himself above all men, had always kept a touching reverence for Dumas. He must help his sad old professor! But how? It is doubtful at this time if Pasteur could have told a silkworm from an angle worm! Indeed, a little later, when he was first given a cocoon to examine, he held it up to his ear, shook it, and cried: “Why, there is something inside it!” Pasteur hated to go South to try to find out what ailed silkworms, he knew he risked a horrid failure by going and he detested failure above everything. But it is one of the charming things about him that in the midst of all his arrogance, his vulgar sureness of himself, he had kept that boyish love and reverence for his old master—so he said to Dumas: “I am in your hands, I'm at your disposal, do with me as you wish—I will go!”

  So he went. He packed up the never complaining Madame Pasteur and the children and a microscope and three energetic and worshiping young assistants and he went into the epidemic that was slaughtering millions of silkworms and ruining the South of France. Knowing less of silkworms and their sicknesses than a babe in swaddling clothes he arrived in Alais; he got there and he learned that a silkworm spins a cocoon round itself and turns into a chrysalid inside the cocoon; he found out that the chrysalid changes into a moth that climbs out and lays eggs—which hatch out the next spring into new broods of young silkworms. The silkworm growers—disgusted at his great ignorance—told him that the disease which was killing their worms was called pébrine, because the sick worms were covered with little black spots that looked like pepper. Pasteur found out that there were a thousand or so theories about the sickness, but that the little pepper spots—and the curious little globules inside the sick worms, wee globules that you could only see with a microscope—were the only facts that were known about it.

  Then Pasteur unlimbered his microscope, before he had got his family settled—he was like one of those trout fishing maniacs who starts to cast without thought of securing his canoe safely on the bank—he unlimbered his microscope, I say, and began to peer at the insides of sick worms, and particularly at these wee globules. Quickly he concluded that the globules were a sure sign of the disease. Fifteen days after he had come to Alais he called the Agricultural Committee together and told them: “At the moment of egg-laying put aside each couple of moths, the father and the mother. Let them mate; let the mother lay her eggs—then pin the father and mother moths down onto a little board, slit open their bellies and take out a little of the fatty tissue under their skin; put this under a microscope and look for those tiny globules. If you can't find any, you can be sure the eggs are sound—you can use those eggs for new silkworms in the spring.”

  The committee looked at the shining microscope. “We farmers can't run a machine like that,” they objected. They were suspicious, they didn't believe in this newfangled machine. Then the salesman that was in Pasteur came to the front. “Nonsense!” he answered. “There is an eight-year-old girl in my laboratory who handles this microscope easily and is perfectly able to spot these little globules—these corpuscles—and then you grown men try to tell me you couldn't learn to use a microscope!” So he shamed them. And the committee obediently bought microscopes and tried to follow his directions. Then Pasteur started a hectic life; he was everywhere around the tragic silk country, lecturing, asking innumerable questions, teaching the farmers to use microscopes, rushing back to the laboratory to direct his assistants—he directed them to do complicated experiments that he hadn't time to do, or even watch, himself—and in the evenings he dictated answers to letters and scientific papers and speeches to Madame Pasteur. The next morning he was off again to the neighboring towns, cheering up despairing farmers and haranguing them. . .

  But the next spring his bubble burst, alas. The next spring, when it came time for the worms to climb their mulberry twigs to spin their silk cocoons, there was a horrible disaster. His confident prophecy to the farmers did not come true. These honest people glued their eyes to their microscopes to pick out the healthy moths, so as to get healthy eggs, eggs without the evil globules in them—and these supposed healthy eggs hatched worms, sad to tell, who grew miserably, languid worms who would not eat, strange worms who failed to molt, sick worms who shriveled up and died, lazy worms who hung around at the bottoms of their twigs, not caring whether there was ever another silk stocking on the leg of any fine lady in the world.

  Poor Pasteur! He had been so busy trying to save the silkworm industry that he hadn't taken time to find out what really ailed the silkworms. Glory had seduced him into becoming a mere savior—for a moment he forgot that Truth is a will o' the wisp that can only be caught in the net of glory-scorning patient experiment. . .

  Some silkworm raisers laughed despairing laughs at him—others attacked him bitterly; dark days were on him. He worked the harder for them, but he couldn't find bottom. He came on broods of silkworms who
fairly galloped up the twigs and proceeded to spin elegant cocoons—then at the microscope he found these beasts swarming with the tiny globules. He discovered other broods that sulked on their branches and melted away with a gassy diarrhoea and died miserably—but in these be could find no globules whatever. He became completely mixed up; he began to doubt whether the globules had anything to do with the disease. Then to make things worse, mice got into the broods of his experimental worms and made cheerful meals on them and poor Duclaux, Maillot and Gernez had to stay up by turns all night to catch the raiding mice; next morning everybody would be just started working when black clouds appeared in the West, and all of them—Madame Pasteur and the children bringing up the rear—had to scurry out to cover up the mulberry trees. In the evenings Pasteur had to settle his tired back in an armchair, to dictate answers to peeved silkworm growers who had lost everything—using his method of sorting eggs.

  After a series of such weary months, his instinct to do experiments, this instinct—and the Goddess of Chance—came together to save him. He pondered to himself: “I've at least managed to scrape together a few broods of healthy worms—if I feed these worms mulberry leaves smeared with the discharges of sick worms, will the healthy worms die?” He tried it, and the healthy worms died sure enough, but, confound it! the experiment was a fizzle again—for instead of getting covered with pepper spots and dying slowly in twenty-five days or so, as worms always do of pébrine—the worms of his experiment curled up and passed away in seventy-two hours. He was discouraged, he stopped his experiments; his faithful assistants worried about him—why didn't he try the experiment over?

  At last Gernez went off to the north to study the silk worms of Valenciennes, and Pasteur, not clearly knowing the reason why, wrote to him and asked him to do that feeding experiment up there. Gernez had some nice broods of healthy worms. Gernez was sure in his own head—no matter what his chief might think—that the wee globules were really living things, parasites, assassins of the silkworm. He took forty healthy worms and fed them on good healthy mulberry leaves that had never been fed on by sick beasts. These worms proceeded to spin twenty-seven good cocoons and there were no globules in the moths that came from them. He smeared some other leaves with crushed-up sick moths and fed them to some day-old worms—and these worms wasted away to a slow death, they became covered with pepper spots and their bodies swarmed with the sub-visible globules. He took some more leaves with crushed-up sick moths and fed these to some old worms just ready to spin cocoons; the worms lived to spin the cocoons, but the moths that came out of the cocoons were loaded with the globules, and the worms from their eggs came to nothing. Gernez was excited—and he became more excited when still nights at his microscope showed him that the globules increased tremendously as the worms faded to their deaths. . .

  Gernez hurried to Pasteur. “It is solved,” he cried, “the little globules are alive—they are parasites!—They are what make the worms sick!”

  It was six months before Pasteur was convinced that Gernez was right, but when at last he understood, he swooped back on his work, and once more called the Committee together. “The little corpuscles are not only a sign of the disease, they are its cause. These globules are alive, they multiply, they force themselves into every part of the moth's body. Where we made our mistake was to examine only a little part of the moth, we only looked under the skin of the moth's belly—we've got to grind up the whole beast and examine all of it. Then if we do not find the globules we can safely use the eggs for next year's worms!”

  The committee tried the new scheme and it worked—the next year they had fine worms that gave them splendid yields of silk.

  Pasteur saw now that the little globule, the cause of the pébrine, came from outside the worm—it did not rise by itself inside the worm—and he went everywhere, showing the farmers how to keep their healthy worms away from all contact with leaves that sick worms had soiled. Then suddenly he fell a victim of a hemorrhage of the brain—he nearly died, but when he heard that work of building his new laboratory had been stopped, frugally stopped in expectation of his death, he was furious and made up his mind to live. He was paralyzed on one side after that—he never got over it—but he earnestly read Dr. Smiles' book, “Self Help” and vigorously decided to work in spite of his handicap. At a time when he should have stayed in his bed, or have gone to the seaside, he staggered to his feet and limped to the train for the South, exclaiming indignantly that it would be criminal not to finish saving the silkworms while so many poor people were starving! All Frenchmen, excepting a few nasty fellows who called it a magnificent gesture, joined in praising him and adoring him.

  For six years Pasteur struggled with the diseases of silkworms. He had no sooner settled pébrine than another malady of these unhappy beasts popped up, but he knew his problem and found the microbe of this new disease much more quickly. Tears of joy were in the voice of old Dumas now as he thanked his dear Pasteur—and the mayor of the town of Alais talked enthusiastically of raising a golden statue to the great Pasteur.

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  He was forty-five. He wallowed in this glory for a moment, and then—having saved the silkworm industry, with the help of God and Gernez—he raised his eyes toward one of those bright, impossible, but always partly true visions that it was his poet's gift to see. He raised his artist's eyes from the sicknesses of silkworms to the sorrows of men, he sounded a trumpet call of hope to suffering mankind:

  “It is in the power of man to make parasitic maladies disappear from the face of the globe, if the doctrine of spontaneous generation is wrong, as I am sure it is.”

  The siege of Paris in the bitter winter of 1870 had driven him from his work to his old home in the Jura hills. He wandered pitifully around battlefields looking for his son who was a sergeant. Here he worked himself up into a tremendous hate, a hate that never left him, of all things German; he became a professional patriot. “Every one of my works will bear on its title page, 'Hatred to Prussia. Revenge! Revenge!'” he shrieked, good loyal Frenchman that he was. Then with a magnificent silliness he proceeded to make his next research a revenge research. Even he had to admit that French beer was much inferior to the beer of the Germans. Well—he would make the beer of France better than the beer of Germany—he must make the French beer the peer of beers, no, the emperor of all beers of the world!

  He embarked on vast voyages to the great breweries of France and here he questioned everybody from the brewmaster in his studio to the lowest workman that cleaned out the vats. He journeyed to England and gave advice to those red-faced artists who made English porter and to the brewers of the divine ale of Bass and Burton. He trained his microscope on the must of a thousand beer vats to watch the yeast globules at their work of budding and making alcohol. Sometimes he discovered the same kind of miserable sub-visible beings that he had found in sick wines years before, and he told the brewers that if they would heat their beer, they would keep these invaders out; he assured them that then they would be able to ship their beer long distances, that then they would be able to brew the most incredibly marvelous of all beers! He begged money for his laboratory from brewers, explaining to them how they would be repaid a thousand fold, and with this money he turned his old laboratory at the Normal School into a small scientific brewery that glittered with handsome copper vats and burnished kettles.

  But in the midst of all this feverish work, alas, Pasteur grew sick of working on beer. He hated the taste of beer just as he loathed the smell of tobacco smoke; to his disgust he found that he would have to become a good beer-taster in order to become a great beer-scientist, to his dismay he discovered that there was much more to the art of brewing than simply keeping vicious invading microbes out of beer vats. He puckered his snub nose and buried his serious mustache in foamy mugs and guzzled determined draughts of the product of his pretty kettles—but he detested this beer, even good beer, in fact all beer. Bertin, the physics professor, his old friend, smacked his lips and laughed at him as
he swallowed great gulps of beer that Pasteur had denounced as worthless. Even the young assistants snickered—but never to his face. Pasteur, most versatile of men, was after all not a god. He was an investigator and a marvelous missionary—but beer-loving is a gift that is born in a limited number of connoisseurs, just as the ear for telling good music from trash is born in some men!

  Pasteur did help the French beer industry. For that we have the testimony of the good brewers themselves. It is my duty to doubt, however, the claims of those idolizers of his who insist that he made French the equal of German beer. I do not deny this claim, but I beg that it be submitted to a commission, one of those solemn impartial international commissions, the kind of commission that Pasteur himself so often demanded to decide before all the world whether he or his detested opponents were in the right. . .

  Pasteur's life was becoming more and more unlike the austere cloistered existence that most men of science lead. His experiments became powerful answers to the objections that swarmed on every side against his theory of germs, they became loud public answers to such objections—rather than calm quests after facts; but in spite of his dragging science into the market place, there is no doubt that his experiments were marvelously made, that they fired the hopes and the imagination of the world. He got himself into a noisy argument on the way yeasts turn grape juice into wine, with two French naturalists, Frémy and Trécul. Frémy admitted that yeasts were needed to make alcohol from grape juice, but he argued ignorantly before the amused Academy that yeasts were spontaneously generated inside of grapes. The wise men of the Academy pooh-poohed; they were amused, all except Pasteur.