Microbe Hunters Page 3

  If Antony Leeuwenhoek failed to see the germs that cause human disease, if he had too little imagination to predict the rôle of assassin for his wretched creatures, he did show that sub-visible beasts could devour and kill living beings much larger than they were themselves. He was fussing with mussels, shellfish that he dredged up out of the canals of Delft. He found thousands of them unborn inside their mothers. He tried to make these young ones develop outside their mothers in a glass of canal water. “I wonder,” he muttered, “why our canals are not choked with mussels, when the mothers have each one so many young ones inside them!” Day after day he poked about in his glass of water with its slimy mass of embryos, he turned his lens on to them to see if they were growing—but what was this? Astounded he watched the fishy stuff disappear from between their shells—it was being gobbled up by thousands of tiny microbes that were attacking the mussels greedily. . .

  “Life lives on life—it is cruel, but it is God's will,” he pondered. “And it is for our good, of course, because if there weren't little animals to eat up the young mussels, our canals would be choked by those shellfish, for each mother has more than a thousand young ones at a time!” So Antony Leeuwenhoek accepted everything and praised everything, and in this he was a child of his time, for in his century searchers had not yet, like Pasteur who came after them, begun to challenge God, to shake their fists at the meaningless cruelties of nature toward mankind, her children. . .

  He passed eighty, and his teeth came loose as they had to even in his strong body; he didn't complain at the inexorable arrival of the winter of his life, but he jerked out that old tooth and turned his lens onto the little creatures he found within that hollow root—why shouldn't he study them once more? There might be some little detail he had missed those hundred other times! Friends came to him at eighty-five and told him to take it easy and leave his studies. He wrinkled his brow and opened wide his still bright eyes: “The fruits that ripen in autumn last the longest!” he told them—he called eighty-five the autumn of his life!

  Leeuwenhoek was a showman. He was very pleased to hear the ohs and ahs of people—they must be philosophical people and lovers of science, mind you!—whom he let peep into his sub-visible world or to whom he wrote his disjointed marvelous letters of description. But he was no teacher. “I've never taught one,” he wrote to the famous philosopher Leibniz, “because if I taught one, I'd have to teach others. . . I would give myself over to a slavery, whereas I want to stay a free man.”

  “But the art of grinding fine lenses and making observations of these new creatures will disappear from the earth, if you don't teach young men,” answered Leibniz.

  “The professors and students of the University of Leyden were long ago dazzled by my discoveries, they hired three lens grinders to come to teach the students, but what came of it?” wrote that independent Dutchman.

  “Nothing, so far as I can judge, for almost all of the courses they teach there are for the purpose of getting money through knowledge or for gaining the respect of the world by showing people how learned you are, and these things have nothing to do with discovering the things that are buried from our eyes. I am convinced that of a thousand people not one is capable of carrying out such studies, because endless time is needed and much money is spilled and because a man has always to be busy with his thoughts if anything is to be accomplished. . .”

  That was the first of the microbe hunters. In 1723, when he was ninety-one years old and on his deathbed, he sent for his friend Hoogvliet. He could not lift his hand. His once glowing eyes were rheumy and their lids were beginning to stick fast with the cement of death. He mumbled:

  “Hoogvliet, my friend, be so good as to have those two letters on the table translated into Latin. . . Send them to London to the Royal Society. . .”

  So he kept his promise made fifty years before, and Hoogvliet wrote, along with those last letters: “I send you, learned sirs, this last gift of my dying friend, hoping that his final word will be agreeable to you.”

  So he passed, this first of the microbe hunters. You will read of Spallanzani, who was much more brilliant, of Pasteur who had a thousand times his imagination, of Robert Koch who did much more immediate apparent good in lifting the torments that microbes bring to men—these and all the others have much more fame to-day. But not one of them has been so completely honest, so appallingly accurate as this Dutch janitor, and all of them could take lessons from his splendid common sense.

  2. SPALLANZANI:

  Microbes Must Have Parents!

  1

  “Leeuwenhoek is dead, it is too bad, it is a loss that cannot be made good. Who now will carry on the study of the little animals?” asked the learned men of the Royal Society in England, asked Réaumur and the brilliant Academy in Paris. Their question did not wait long for an answer, for the janitor of Delft had hardly closed his eyes in 1723 for the long sleep that he had earned so well, when another microbe hunter was born, in 1729 a thousand miles away in Scandiano in northern Italy. This follower of Leeuwenhoek was Lazzaro Spallanzani, a strange boy who lisped verses while he fashioned mud-pies; who forgot mudpies to do fumbling childish and cruel experiments with beetles and bugs and flies and worms. Instead of pestering his parents with questions he examined living things in nature, by pulling legs and wings off them, by trying to stick them back on again. He must find out how things worked; he didn't care so very much what they looked like.

  Like Leeuwenhoek, the young Italian had to fight to become a microbe hunter against the wishes of his family. His father was a lawyer and did his best to get Lazzaro interested in long sheets of legal foolscap—but the youngster sneaked away and skipped flat stones over the surface of the water, and wondered why the stones skipped and didn't sink.

  In the evenings he was made to sit down before dull lessons, but when his father's back was turned he looked out of the window at the stars that gleamed in the velvet black Italian sky, and next morning lectured about them to his playmates until they called him “The Astrologer.”

  On holidays he pushed his burly body through the woods near Scandiano, and came wide-eyed upon foaming natural fountains. These made him stop his romping, and caused him to go home sunk in unboyish thought. What caused these fountains? His folks and the priest had told him they had sprung in olden times from the tears of sad, deserted, beautiful girls who were lost in the woods. . .

  Lazzaro was a dutiful son—and a politician of a son—so he didn't argue with his father or the priest. But to himself he said “bunk” to their explanation, and made up his mind to find out, some day, the real why and wherefore of fountains.

  Young Spallanzani was just as determined as Leeuwenhoek had been to find out the hidden things of nature, but he set about getting to be a scientist in an entirely different way. He pondered: “My father insists that I study law, does he?” He kept up the pretense of being interested in legal documents—but in every spare moment he boned away at mathematics and Greek and French and Logic—and during his vacations watched skipping stones and fountains, and dreamed about understanding the violent fireworks of volcanoes. Then craftily he went to the noted scientist, Vallisnieri, and told this great man what he knew. “But you were born for a scientist,” said Vallisnieri, “you waste time foolishly, studying lawbooks.”

  “Ah, master, but my father insists.”

  Indignantly Vallisnieri went to Spallanzani senior and scolded him for throwing away Lazzaro's talents on the merely useful study of law. “Your boy,” he said, “is going to be a searcher, he will honor Scandiano, and make it famous—he is like Galileo!”

  And the shrewd young Spallanzani went to the University at Reggio, with his father's blessing, to take up the career of scientist.

  At this time it was much more respectable and safe to be a scientist than it had been when Leeuwenhoek began his first grinding of lenses. The Grand Inquisition was beginning to pull in its horns. It preferred jerking out the tongues of obscure alleged criminals and burning
the bodies of unknown heretics, to persecuting Servetuses and Galileos. The Invisible College no longer met in cellars or darkened rooms, and learned societies all over were now given the generous support of parliaments and kings. It was not only beginning to be permitted to question superstitions, it was becoming fashionable to do it. The thrill and dignity of real research into nature began to elbow its way into secluded studies of philosophers. Voltaire retired for years into the wilds of rural France to master the great discoveries of Newton, and then to popularize them in his country. Science even penetrated into brilliant and witty and immoral drawing-rooms, and society leaders like Madame de Pompadour bent their heads over the forbidden Encyclopedia—to try to understand the art and science of the making of rouge and silk stockings.

  Along with this excited interest in everything from mechanics of the stars to the caperings of little animals, the people of Spallanzani's glittering century began to show an open contempt for religion and dogmas, even the most sacred ones. A hundred years before men had risked their skins to laugh at the preposterous and impossible animals that Aristotle had gravely put into his books on biology. But now, they could openly snicker at the mention of his name and whisper: “Because he's Aristotle it implies that he must be believed e'en though he lies.” Still there was plenty of ignorance in the world, and much pseudo-science—even in the Royal Societies and Academies. And Spallanzani, freed from the horror of an endless future of legal wranglings, threw himself with vigor into getting all kinds of knowledge, into testing all kinds of theories, into disrespecting all kinds of authorities no matter how famous, into association with every kind of person, from fat bishops, officials, and professors to outlandish actors and minstrels.

  He was the very opposite of Leeuwenhoek, who so patiently had ground lenses, and looked at everything for twenty years before the learned world knew anything about him. At twenty-five Spallanzani made translations of the ancient poets, and criticized the standard and much admired Italian translation of Homer. He brilliantly studied mathematics with his cousin, Laura Bassi, the famous woman professor of Reggio. He now skipped stones over the water in earnest, and wrote a scientific paper on the mechanics of skipping stones. He became a priest of the Catholic Church, and helped support himself by saying masses.

  Despising secretly all authority, he got himself snugly into the good graces of powerful authorities, so that he might work undisturbed. Ordained a priest, supposed to be a blind follower of the faith, he fell savagely to questioning everything, to taking nothing for granted—excepting the existence of God, of some sort of supreme being. At least if he questioned this he kept it—rogue that he was—strictly to himself. Before he was thirty years old he had been made professor at the University of Reggio, talking before enthusiastic classes that listened to him with saucer-eyes. Here he started his first work on the little animals, those weird new little beings that Leeuwenhoek had discovered. He began his experiments on them as they were threatening to return to that misty unknown from which the Dutchman had dredged them up.

  The little animals had got themselves involved in a strange question, in a furious fight, and had it not been for that, they might have remained curiosities for centuries, or even have been completely forgotten. This argument, over which dear friends grew to hate each other and about which professors tried to crack the skulls of priests, was briefly this: Can living things arise spontaneously, or does every living thing have to have parents? Did God create every plant and animal in the first six days, and then settle down to be Managing Director of the universe, or does He even now amuse Himself by allowing new animals to spring up in humorous ways?

  In Spallanzani's time the popular side was the party that asserted that life could arise spontaneously. The great majority of sensible people believed that many animals did not have to have parents—that they might be the unhappy illegitimate children of a disgusting variety of dirty messes. Here, for example, was a supposedly sure recipe for getting yourself a good swarm of bees. Take a young bullock, kill him with a knock on the head, bury him under the ground in a standing position with his horns sticking out. Leave him there for a month, then saw off his horns—and out will fly your swarm of bees.

  2

  Even the scientists were on this side of the question. The English naturalist Ross announced learnedly that: “To question that beetles and wasps were generated in cow dung is to question reason, sense, and experience.” Even such complicated animals as mice didn't have to have mothers or fathers—if anybody doubted this, let him go to Egypt, and there he would find the fields literally swarming with mice, begot of the mud of the River Nile—to the great calamity of the inhabitants!

  Spallanzani heard all of these stories which so many important people were sure were facts, he read many more of them that were still more strange, he watched students get into brawls in excited attempts to prove that mice and bees didn't have to have fathers or mothers. He heard all of these things—and didn't believe them. He was prejudiced. Great advances in science so often start from prejudice, on ideas got not from science but straight out of a scientist's head, on notions that are only the opposite of the prevailing superstitious nonsense of the day. Spallanzani had violent notions about whether life could rise spontaneously; for him it was on the face of things absurd to think that animals—even the wee beasts of Leeuwenhoek—could arise in a haphazard way from any old thing or out of any dirty mess. There must be law and order to their birth, there must be a rime and reason! But how to prove it?

  Then one night, in his solitude, he came across a little book, a simple and innocent little book, and this book told him of an entirely new way to tackle the question of how life arises. The fellow who wrote the book didn't argue with words—he just made experiments—and God! thought Spallanzani, how clear are the facts he demonstrates. He stopped being sleepy and forgot the dawn was coming, and read on. . .

  The book told him of the superstition about the generation of maggots and flies, it told of how even the most intelligent men believed that maggots and flies could arise out of putrid meat. Then—and Spallanzani's eyes nearly popped out with wonder, with excitement, as he read of a little experiment that blew up this nonsense, once and for always.

  “A great man, this fellow Redi, who wrote this book,” thought Spallanzani, as he took off his coat and bent his thick neck toward the light of the candle. “See how easy he settles it! He takes two jars and puts some meat in each one. He leaves one jar open and then puts a light veil over the other one. He watches—and sees flies go down into the meat in the open pot—and in a little while there are maggots there, and then new flies. He looks at the jar that has the veil over it—and there are no maggots or flies in that one at all. How easy! It is just a matter of the veil keeping the mother flies from getting at the meat. . . But how clever, because for a thousand years people have been getting out of breath arguing about the question—and not one of them thought of doing this simple experiment that settles it in a moment.”

  Next morning it was one jump from the inspiring book to tackling this same question, not with flies, but with the microscopic animals. For all the professors were saying just then that though maybe flies had to come from eggs, little sub-visible animals certainly could rise by themselves.

  Spallanzani began fumblingly to learn how to grow wee beasts, and how to use a microscope. He cut his hands and broke large expensive flasks. He forgot to clean his lenses and sometimes saw his little animals dimly through his fogged glasses—just as you can faintly make out minnows in the water riled up by your net. He raved at his blunders; he was not the dogged worker that Leeuwenhoek had been—but despite his impetuousness he was persistent—he must prove that these yarns about the animalcules were yarns, nothing more. But wait! “If I set out to prove something I am no real scientist—I have to learn to follow where the facts lead me—I have to learn to whip my prejudices. . . ” And he kept on learning to study little animals, and to observe with a patient, if not an unprejudiced
eye, and gradually he taught the vanity of his ideas to bow to the hard clearness of his facts.

  At this time another priest, named Needham, a devout Catholic who liked to think he could do experiments, was becoming notorious in England and Ireland, claiming that little microscopic animals were generated marvelously in mutton gravy. Needham sent his experiments to the Royal Society, and the learned Fellows deigned to be impressed.

  He told them how he had taken a quantity of mutton gravy hot from the fire, and put the gravy in a bottle, and plugged the bottle up tight with a cork, so that no little animals or their eggs could possibly get into the gravy from the air. Next he even went so far as to heat the bottle and its mutton gravy in hot ashes. “Surely,” said the good Needham, “this will kill any little animals or their eggs, that might remain in the flask.” He put this gravy flask away for a few days, then pulled the cork—and marvel of marvels—when he examined the stuff inside with his lens, he found it swarming with animalcules.

  “A momentous discovery, this,” cried Needham to the Royal Society, “these little animals can only have come from the juice of the gravy. Here is a real experiment showing that life can come spontaneously from dead stuff!” He told them mutton-gravy wasn't necessary—a soup made from seeds or almonds would do the same trick.

  The Royal Society and the whole educated world were excited by Needham's discovery. Here was no Old Wives' tale. Here was hard experimental fact; and the heads of the Society got together and thought about making Needham a Fellow of their remote aristocracy of learning. But away in Italy, Spallanzani was reading the news of Needham's startling creation of little animals from mutton gravy. While he read he knit his brows, and narrowed his dark eyes. At last he snorted: “Animalcules do not arise by themselves from mutton gravy, or almond seeds, or anything else! This fine experiment is a fraud—maybe Needham doesn't know it is—but there's a nigger in the wood pile somewhere. I'm going to find it. . .”