Microbe Hunters Read online

  Then one day he ran on to a curious sight under his microscope—a strange transformation of his microbes that gave him a clew to his question; and Koch sat down on his stool in his eight-by-ten laboratory in East Prussia and solved the mystery of the cursed fields and mountains of France. He had kept a hanging-drop, in its closed glass well, at the temperature of a mouse's body for twenty-four hours. “Ah, this ought to be full of nice long threads of bacilli,” he muttered, and looked down the tube of his microscope—“What's this?” he cried.

  The outlines of the threads had grown dim, and each thread was speckled, through its whole length, with little ovals that shone brightly like infinitely tiny glass beads, and these beads were arranged along the threads as perfectly as a string of pearls.

  To himself Koch muttered guttural curses. “Other microbes have doubtless gotten into my hanging-drop,” he grumbled, but when he looked very carefully he saw that wasn't true, for the shiny little beads were inside the threads—the bacilli that made up the threads have turned into these beads! He dried this hanging-drop, and put it away carefully, for a month or so, and then as luck would have it, looked at it once more through his lens. The strange strings of beads were still there, shining as brightly as ever. Then an idea for an experiment got hold of him—he took a drop of pure fresh watery fluid from the eye of an ox. He placed it on the dried-up smear with its months-old bacilli that had turned into beads. His head swam with confused surprise as he looked, and watched the beads grow back into the ordinary bacilli, and then into long threads once more. It was outlandish!

  “Those queer shiny beads have turned back into ordinary anthrax bacilli again,” cried Koch, “the beads must be the spores of the microbe—the tough form of them that can stand great heat, and cold, and drying. . . That must be the way the anthrax microbe can keep itself alive in the fields for so long—the bacilli must turn into spores. . .”

  Then Koch launched himself into thorough, ingenious tests to see if his quick guess was right. Expertly now he took spleens out of mice which had perished of anthrax—he lifted this deadly stuff out carefully with heated knives and forceps. Protected from all chance of contamination by stray microbes of the air, he kept the spleens for a day at the temperature of a mouse's body, and, sure enough, the microbes, every thread of them, turned into glassy spores.

  Then in experiments that kept him incessantly in his dirty little room he found that the spores remained alive for months, ready to hatch out into deadly bacilli the moment he put them into a fresh drop of the watery fluid of ox-eyes, or the instant he stuck them, on one of his thin slivers, into the root of a mouse's tail.

  “These spores never form in an animal while he is still alive—they only appear after he has died, and then only when he is kept very warm,” said Koch, and he proved this beautifully by clapping spleens into an ice chest—and in a few days this stuff, smeared on splinters, was no more dangerous than if he had shot so much beefsteak into his mice.

  It was now the year 1876, and Koch was thirty-four years old, and at last he emerged out of the bush of Wollstein, to tell the world—stuttering a little—that it was at last proved that microbes were the cause of disease. Koch put on his best suit and his gold-rimmed spectacles and packed up his microscope, a few hanging-drops in their glass cells, swarming with murderous anthrax bacilli; and besides these things he bundled a cage into the train with him, a cage that bounced a little with several dozen healthy white mice. He took a train for Breslau to exhibit his anthrax microbes and the way they kill mice, and the weird way in which they turn into glassy spores—he wanted to demonstrate these things to old Professor Cohn, the botanist at the University, who had sometimes written him encouraging letters.

  Professor Cohn, who had been amazed at the marvelous experiments about which the lonely Koch had written him, old Cohn snickered when he thought of how this greenhorn doctor—who had no idea, himself, of how original he was—would surprise the highbrows of the University. He sent out invitations to the most eminent medicoes of the school to come to the first night of Koch's show.

  4

  And they came. To hear the unscientific backwoodsman—they came. They came maybe out of friendliness to old Professor Cohn. But Koch didn't lecture—he was never much at talking—instead of telling them that his microbes were the true cause of anthrax, he showed these sophisticated professors. For three days and nights he showed them, taking them in swift steps through those searchings he had sweated at—groping and failing often—for years. Never was there a greater come-down for bigwigs who had arrived prepared to be indulgent to a nobody. Koch never argued once, he never bubbled and raved and made prophecies—but he slipped slivers into mouse tails with an unearthly cleverness, and the experienced professors of pathology opened their eyes to see him handle his spores and bacilli and microscopes like a sixty-year-old master. It was a knock-out!

  At last Professor Cohnheim, one of the most skillful scientists in the study of diseases in all of Europe, could hold himself no longer. He rushed from the hall, hurried to his own laboratory, and burst into the room where his young student searchers were working. He shouted to them: “My boys, drop everything and go see Doctor Koch—this man has made a great discovery!” Cohnheim gasped to get his breath.

  “But who is this Koch, Herr Professor? We've never even heard of him.”

  “No matter who he is—it is a great discovery, so exact, so simple. It is astounding! This Koch is not a professor, even. . . He hasn't even been taught how to do research! He's done it all by himself, complete—there is nothing more to do!”

  “But what is this discovery, Herr Professor?”

  “Go, I tell you, every one of you, and see for yourselves. It is the most marvelous discovery in the realm of microbes. . . he will make us all ashamed of ourselves. . . Go—” But by this time, all of them, including Paul Ehrlich, had disappeared through the door.

  Seven years before, Pasteur had foretold: “It is within the power of man to make parasitic maladies disappear from the face of the earth. . . ” And when he said these words the wisest doctors in the world put their fingers to their heads, thinking: “The poor fellow is cracked!”

  But this night Robert Koch had shown the world the first step toward the fulfillment of Pasteur's seemingly insane vision: “Tissues from animals dead of anthrax, whether they are fresh, or putrid, or dried, or a year old, can only produce anthrax when they contain bacilli or the spores of bacilli. Before this fact all doubt must be laid aside that these bacilli are the cause of anthrax,” he told them finally, as if his experiments had not convinced them already. And he ended by telling his amazed audience how to fight this terrible disease—how his experiments showed a way to stamp it out in the end: “All animals that die of anthrax must be destroyed at once after they die—or if they can not be burned, they should be buried deep in the ground, where the earth is so cold that the bacilli cannot turn into the tough, long-lived spores. . .”

  So it was that in these three days at Breslau this Koch put a sword Excalibur into the hands of men, with which to begin the fight against their enemies the microbes, their fight against lurking death; so it was that he began to change the whole business of doctors from a foolish hocus-pocus with pills and leeches into an intelligent fight where science instead of superstition was the weapon.

  Koch fell among friends—among honest generous men—at Breslau. Cohn and Cohnheim, instead of trying to steal his stuff (there are no fewer shady fellows in science than in any other human activity), these two professors immediately set up a great whooping for Koch, an applause that echoed over Europe and made Pasteur a bit uneasy for his job as Dean of the Microbe Hunters. These two friends began to bombard the authorities of the Imperial Health Office at Berlin about this unknown that Germany ought to be proud of—they did their best to give Koch a chance to do nothing but chase the microbes of disease, to get away from that dull practice of his.

  Left alone, or snubbed at Breslau, he might easily have gone b
ack to Wollstein to his business of telling people to stick out their tongues. In short, men of science have either to be showmen—as were the magnificent Spallanzani and the passionate Pasteur—or they have to have impresarios.

  Koch packed up Emmy and his household goods and moved to Breslau and was given a job as city physician at four hundred and fifty dollars a year, and was supposed to eke out his living with the private patients that would undoubtedly flock to be treated by such a brilliant man.

  So thought Cohn and Cohnheim. But the doorbell of Koch's little office didn't ring, hardly any one came to ring it, and so Koch learned that it is a great disadvantage for a doctor to be brainy and inquire into the final causes of things. He went back to Wollstein, beaten, and here from 1878 to 1880 he made long jumps ahead in microbe hunting once more—spying on and tracking down the strange sub-visible beings that cause the deadly infections of wounds in animals and in human beings. He learned to stain all kinds of bacilli with different colored dyes, so that the very tiniest microbe would stand out clearly. In some unknown way he saved money enough to buy a camera and stuck its lens against his microscope and learned—no one helping him—how to take pictures of these little creatures.

  “You'll never convince the world about these murderous bugs until you can show them photographs,” Koch said. “Two men can't look through one microscope at the same time, no two men will ever draw the same picture of a germ—so there'll always be wrangling and confusion. . . But these photographs can't lie—and ten men can study them, and come to an agreement on them. . . ” So it was that Koch began to try to introduce rime and reason into the baby science of microbe hunting which up till now had been as much a wordy brawl as a quest for knowledge.

  Meanwhile his friends at Breslau had not forgotten him and in 1880—it was like some bush-leaguer breaking into the big team—he was told by the government to come to Berlin and be Extraordinary Associate of the Imperial Health Office. Here he was given a fine laboratory and a sudden undreamed-of wealth of apparatus and two assistants and enough money so that he could spend sixteen or eighteen hours of his working day among his stains and tubes and cluttering guinea-pigs.

  By this time the news of Koch's discoveries had spread to all of the laboratories of Europe and had crossed the ocean and inflamed the doctors of America. The vast exciting Battle of the Germ Theory was on! Every medical man and Professor of Diseases who knew—or thought he knew—the top end from the bottom of a microscope set out to become a microbe hunter. Every week brought glad news of the supposed discovery of some new deadly microbe, surely the assassin of suffering from cancer or typhoid fever or consumption. One enthusiast would shout across continents that he had discovered a kind of pan-germ that caused all diseases from pneumonia to the pip—only to be forgotten for an idiot who might claim that he had proved one disease, let us say consumption, to be the result of the attack of a hundred different species of microbes.

  So great was the enthusiasm about germs—and the confusion—that Koch's discoveries were in danger of being laughed into obscurity along with the vast magazines full of balderdash that were being printed on the subject of the germ theory.

  And yet to-day we demand with a great hue and cry more laboratories, more microbe hunters, better paid searchers to free us from the diseases that scourge us. How futile! For progress, God must send us a few more infernal marvelous searchers of the kind of Robert Koch.

  But in the midst of the danger that foolish enthusiasm would kill the new science of microbe hunting, Koch kept his head, and sat down to find a way to grow germs pure. “One germ, one kind of germ only, causes one definite kind of disease—every disease has its own specific microbe, I know that,” said Koch—without knowing it. “I've got to find a sure easy method of growing one species of germ away from all other contaminating ones that are always threatening to sneak in!”

  But how to cage one kind of microbe? All manner of weird machines were being invented to try to keep different sorts of germs apart. Several microbe hunters devised apparatus so complicated that when they had finished building it they probably had already forgotten what they set out to invent it for. To keep stray germs of the air from falling into their bottles some heroic searchers did their inoculations in an actual rain of poisonous germicides!

  5

  Until, one day, Koch—who frankly admitted it was by accident—looked at the flat surface of half of a boiled potato left on a table in his laboratory. “What's this, I wonder?” he muttered, as he stared at a curious collection of little colored droplets scattered on the surface of the potato. “Here's a gray colored drop, here's a red one, there's a yellow, a violet one—these little specks must be made up of germs from the air. I'll have a look at them.”

  He stuck his short-sighted eyes down close to the potato so that his scraggly little beard almost dragged in it; he got ready his thin plates of glass and polished off the lenses of his microscope.

  With a slender wire of platinum he fished delicately into one of the gray droplets and put a bit of its slimy stuff in a little pure water between two bits of glass, under his microscope. Here he saw a swarm of bacilli, swimming gently about, and every one of these microbes looked exactly like his thousands of brothers in this drop. Then Koch peered at the bugs from a yellow droplet on the potato, and at those of a red one and a violet one. The germs from one were round, from another they had the appearance of swimming sticks, from a third microbes looked like living corkscrews—but all the microbes in one given drop were like their brothers, invariably!

  Then in a flash Koch saw the beautiful experiment nature had done for him. “Every one of these droplets is a pure culture of one definite kind of microbe—a pure colony of one species of germs. . . How simple! When germs fall from the air into the liquid soups we have been using—the different kinds of them get all mixed up and swim among each other. . . But when different bugs fall from the air on the solid surface of this potato—each one has to stay where it falls. . . it sticks there. . . then it grows there, multiplies into millions of its own kind. . . absolutely pure!”

  Koch called Loeffler and Gaffky, his two military doctor assistants, and soberly he showed them the change in the whole mixed-up business of microbe hunting that his chance glance at an abandoned potato had brought. It was revolutionary! The three of them set to work with an amazing—loyal Frenchmen might call it stupid—German thoroughness to see if Koch was right. There they sat before the three windows of their room, Koch before his microscope on a high stool in the middle, Loeffler and Gaffky on stools on his left hand and his right—a kind of grimly toiling trinity. They tried to defeat their hopes, but quickly they discovered that Koch's prophecy was an even more true one than he had dreamed. They made mixtures of two or three kinds of germs, mixtures that could never have been untangled by growing in flasks of soup; they streaked these confused species of microbes on the cut flat surfaces of boiled potatoes. And where each separate tiny microbe landed, there it stuck, and grew into a colony of millions of its own kind—and nothing but its own kind.

  Now Koch, who, by this simple experience of the old potato, had changed microbe hunting from a guessing game into something that came near the sureness of a science—Koch, I say, got ready to track down the tiny messengers that bring a dozen murderous diseases to mankind. Up till this time Koch had had very little criticism or opposition from other men of science, mainly because he almost never opened his mouth until he was sure of his results. He told of his discoveries with a disarming modesty and his work was so unanswerably complete—he had a way of seeing the objections that critics might make and replying to them in advance—that it was hard to find protestors.

  Full of confidence Koch went to Professor Rudolph Virchow, by far the most eminent German researcher in disease, an incredible savant, who knew more than there was to be known about a greater number of subjects than any sixteen scientists together could possibly know. Virchow was, in brief, the ultimate Pooh-Bah of German medical science. He had
spoken the very last word on clots in blood vessels and had invented the impressive words, heteropopia, agenesia, and ochronosis, and many others that I have been trying for years to understand the meaning of. He had—with tremendous mistakenness—maintained that consumption and scrofula were two different diseases; but with his microscope he had made genuinely good, even superb descriptions of the way sick tissues look and he had turned his lens into every noisome nook and cranny of twenty-six thousand dead bodies. Virchow had printed—I do not exaggerate—thousands of scientific papers, on every subject imaginable, from the shapes of little German schoolboys' heads and noses to the remarkably small size of the blood vessels in the bodies of sickly green-faced girls.

  Properly awed—as any one would be—Koch tiptoed respectfully into this Presence.

  “I have discovered a way to grow microbes pure, unmixed with other germs, Herr Professor,” the bashful Koch told Virchow, with deference.

  “And how, I beg you tell me, can you do that? It looks to me to be impossible.”

  “By growing them on solid food—I can get beautiful isolated colonies of one kind of microbe on the surface of a boiled potato. . . And now I have invented a better way than that. . . I mix gelatin with beef broth. . . and the gelatin sets and makes a solid surface, and—”

  But Virchow was not impressed. He made a sardonic remark that it was so hard to keep different races of germs from getting mixed up that Koch would have to have a separate laboratory for each species of microbe. . . In short, Virchow was very sniffish and cold to Koch, for he had come to that time of life when ageing men believe that everything is known and there is nothing more to be found out. Koch went away a bit depressed, but not one jot was he discouraged. Instead of arguing and writing papers and making speeches against Virchow he launched himself into the most exciting and superb of all his microbe huntings—he set out to spy upon and discover the most vicious of microbes, that mysterious marauder which each year killed one man, woman, and child out of every seven that died, in Europe, in America. Koch rolled up his sleeves and wiped his gold-rimmed glasses and set out to hunt down the microbe of tuberculosis.