This brilliant discovery formed the basis of the principles of asepsis and antisepsis, giving a new round in the development of surgery, obstetrics and medicine in general.
Thanks to his research, not only pathogens were discovered infectious diseases but were found effective ways fight them. This is how vaccines against anthrax, chicken cholera, swine rubella.
In 1885, Louis Pasteur developed a vaccine against rabies, a disease that in 100% of cases ends in the death of the patient. There is a legend that in childhood, the future scientist saw a man bitten by a rabid wolf. little boy I was very shocked by the terrible picture of cauterization of the bite site with a red-hot iron. But when Pasteur nevertheless created a vaccine, he hesitated for a long time to test the effectiveness of the anti-rabies vaccine in humans. In the end, he decided to test the effect of the vaccine on himself. But chance helped: a boy was brought to him, bitten by a rabid dog. The child would have died anyway, so Pasteur injected the child with tetanus toxoid. After 14 injections, the boy recovered.
From that moment on, Pasteur's fame spread throughout the world. IN different countries Pasteur stations began to open, where they were vaccinated against rabies, anthrax and chicken cholera. In Russia, such a station appeared in 1886 in Odessa and was at that time the second in the world on the initiative of scientists I. I. Mechnikov and N. F. Gamaleya.
Pasteur and his followers, as well as Dr. Jenner, had to fight for the recognition of a new way to prevent infectious diseases. His experiments were questioned and criticized for their scientific views. His belief in his rightness is perfectly illustrated by one story that has already become a legend.
Louis Pasteur studied smallpox bacteria in his laboratory. Suddenly, a stranger appeared to him and introduced himself as the second of a nobleman, who thought that the scientist insulted him. The nobleman demanded satisfaction. Pasteur listened to the messenger and said: "Since they call me, I have the right to choose a weapon. Here are two flasks; one contains smallpox bacteria, the other contains pure water. If the person who sent you agrees to drink one of them, I will drink another" . The duel did not take place.
Pasteur created the world scientific school of microbiologists, many of his students later became major scientists. They own 8 Nobel Prizes. It was Pasteur who laid down one of the cornerstone principles scientific research, evidence, saying the famous "never trust what is not confirmed by experiments."
In the 20th century, prominent scientists developed and successfully used vaccinations against poliomyelitis, hepatitis, diphtheria, measles, mumps, rubella, tuberculosis, and influenza.
Key dates in the history of vaccination
- 1769 - First immunization against smallpox, Dr. Jenner
- 1885 - First immunization against rabies, Louis Pasteur
- 1891 - First successful serotherapy for diphtheria, Emil von Behring
- 1913 - the first prophylactic vaccine against diphtheria, Emil von Behring
- 1921 - first vaccination against tuberculosis
- 1936 - First tetanus vaccination
- 1936 - First influenza vaccination
- 1939 - the first vaccination against tick-borne encephalitis
- 1953 - First trial of an inactivated polio vaccine
- 1956 - polio live vaccine (oral vaccination)
- 1980 - WHO statement on the complete elimination of human smallpox
- 1986 - the first genetically engineered vaccine (HBV)
- 1987 - First conjugate vaccine against Haemophilus influenza B
- 1994 - the first genetically engineered bacterial vaccine (acellular pertussis)
- 1999 - development of a new conjugate vaccine against meningococcal C infection
- 2000 - First conjugate vaccine to prevent pneumonia
Professor V. D. Solovyov
On the fiftieth anniversary of death
Louis Pasteur in the laboratory. On the photo there is an inscription: “In memory of the famous Mechnikov, the creator of the phagocytic theory, from the sincerely devoted Pasteur.
Ru and I.I. Mechnikov (Paris).
In Paris, on Rue Dutot, in a low, modest building surrounded by a cast-iron fence, the Pasteur Institute is located - one of the most interesting scientific institutions in the world. The institute was created according to the plan of the great scientist, whose name it bears. It is built in last years Pasteur's life with funds raised by international voluntary subscription. The Pasteur Institute is the center of microbiological science in France and has played an exceptional role in the development of this science. The best French bacteriologists worked within its walls, as well as many outstanding researchers from other countries, including Russian scientists. The world famous Russian zoologist and microbiologist Ilya Ilyich Mechnikov was at one time the Scientific Director of this Institute. Here, during the lifetime of Pasteur himself, N. F. Gamaleya, now an honorary member of the Academy of Sciences of the USSR, studied bacteriological skills.
The great scientist forever, even after his death, remained at his Institute. On the ground floor, in a small chapel, is his tomb. Above the entrance there is an inscription: “Here lies Pasteur”, and on the sides there are two dates: “1822” and “1895” - the years of birth and death of this wonderful person! Inside, on the marble walls, the most important stages of Louis Pasteur's activity and the years of his discoveries are marked: 1848 - molecular asymmetry. 1857 - enzymes, 1862 - so-called spontaneous generation, 1863 - observations on wine, 1865 - diseases of silkworms, 1871 - observations on beer, 1877 - contagious diseases, 1880 - preventive vaccinations, 1885 - prevention of rabies. This short chronological list reflects the history creative life great scientist.
The son of a tanner from Arbois, a small town in eastern France, and the great-grandson of a serf, Louis Pasteur began his scientific career by studying the theoretical issues of chemistry and chemical crystallography. While still a student at the Normal School in Paris, he began his research on two acids extracted from tartar - tartaric and grape. These two acids are similar in their chemical composition, differ in one feature: the salts of the first of them rotate the plane of polarization to the right, while the salts of the second are optically inactive. Studying the causes of this phenomenon, Pasteur found that during the crystallization of the double ammonium-sodium salt of tartaric acid, two types of crystals stand out, differing from each other in the presence of tiny areas or faces that previously eluded the attention of researchers. These areas were only on one plane of the crystal and caused their incomplete symmetry: sometimes they were on the left, and sometimes on the right side. The pastor collected separately crystals of this salt with facets on the left side and crystals with facets on the right side. From those and other crystals, he isolated the free acid. It turned out that the solution of the first crystals rotates the plane of polarization to the left, while the solution of the second crystals rotates to the right.
In this way, for the first time in the history of chemistry, an optically active substance was artificially obtained from an inactive starting material. Previously, it was believed that the formation of optically active substances can occur only in living organisms. Pasteur explained the optical activity of the right and left tartaric acids by the asymmetry of their molecules. Thus, the concept of molecular asymmetry was introduced into science.
Developing further his method of artificial splitting chemical compounds, Pasteur used the action of molds. This was the beginning of his subsequent work on microbes. Thus, purely chemical research contributed to the creation of one of the most important branches of biology - microbiology. The creation of this science is inextricably linked with the name of Pasteur. What is the cause of contagious diseases, how the infection is transmitted to man - this became clear only when the brilliant mind of Pastor revealed the secret of the driving force of fermentation and directed the development of science along a completely new path.
In the pre-Paster era, that is, 60-70 years ago, mankind had a very vague idea of what contagious diseases were. There were known severe epidemics of cholera, smallpox, plague, which the people called the "black death"; they carried millions of people to the grave. Many other epidemic diseases were known, but what are the causes that cause them, and what should be the measures to combat them, no one knew. How powerless at the time practical medicine, you can see from the example Crimean War 1854 In the French army of more than 300,000 soldiers, about 10,000 were killed, and 85,000 died from diseases and infectious complications of wounds. In other words, in the army, recruited from the most healthy and hardy men, more than a quarter of the entire composition fell victim to disease. The imperfection of surgery of that time is indicated by the enormous mortality from purulent complications of wounds. For example, 92% of the operated patients died during hip amputation. main reason such a terrible loss was the ignorance of those rules of hygiene, which now seem to us the most elementary.
By the age of 35, Louis Pasteur was already a famous scientist. His work on the biological theory of fermentation dates back to this time. Facts have been established with impeccable accuracy showing that all fermentation processes are not simple chemical phenomena, as previously thought, but the result of exposure to microorganisms. Alongside brilliant research, Pasteur established the mechanism of various forms of fermentation, in which living beings of negligible size, belonging either to yeast fungi or bacteria, turned out to be the active principle.
Later, when studying the processes of decay, Pasteur showed that they are also due to the vital activity of microbes. He also understood the great importance that microorganisms have in the transformation of complex protein substances into a primitive state. “If microscopic creatures disappeared from the surface of the earth, then it would quickly be cluttered with dead organic waste and all kinds of animal corpses and plant remains,” Pasteur wrote. “Without their participation, life would soon cease, as the work of death would remain unfinished.”
Where do these microorganisms, which play such a big role in nature, come from, what is their origin?
Pasteur's subsequent classical studies provided a clear answer to this question. It has been proved that there is no spontaneous generation of micro-organisms, that wherever we find micro-organisms they have been introduced from outside. It turned out that it is completely within the power of a person not only to cause, but also to prevent any of the phenomena of fermentation or decay. It turned out that there are microorganisms that can be used by humans, for example, to convert wort into alcohol, alcohol into vinegar. There are also harmful microorganisms, i.e., those that cause contagious diseases.
These remarkable discoveries of Pasteur not only found practical use in industry and agriculture, but they illuminated the whole of medicine with a new light and laid the foundation for a new science that studies microorganisms - microbiology.
The famous English surgeon, Joseph Lister, having understood the full depth of the ideas of his contemporary Pastor, made the following practical conclusion from them: if purulent complications of wounds depend on the action of microorganisms that have got in from the outside, from the air, then it means that for successful treatment it is necessary to prevent microbes from entering the wound. So was introduced into surgery new method treatment of wounds, called the aseptic or aseptic method, which was later replaced by a more advanced one - aseptic. The aseptic method consists in maintaining strict cleanliness and in observing conditions that strictly prevent the penetration of infection, i.e. microorganisms, from environment. “Let me,” Lister wrote to Pastor, “thank you from the bottom of my heart for having opened my eyes to the existence of pyogenic microbes with your brilliant research and thus made it possible to successfully apply the antiseptic method in my work. If you ever come to Edinburgh, I am sure that in our hospital you will get real satisfaction in seeing how high degree Humanity has benefited from your labors.”
Pasteur became interested in medicine, studying the processes of infection and putrefaction. He was particularly interested in the idea of the uniqueness of some infectious diseases. What is the cause of immunity, i.e., the body's ability to resist the action of infectious diseases?
In 1880, while investigating a disease of chickens - chicken cholera, he discovered the remarkable property of the causative agent of this disease - not only to cause disease, but also to create immunity against it. If an artificial breeding or, as they say, a culture of a microbe has become less poisonous due to its long storage outside the body, then it can only cause a weak form of the disease. But after that, immunity is created - immunity to infection even by the strongest culture of microbes of a given disease. Thus, a method was found for the preparation of inoculations, or vaccines, that is, material for inoculations that protect against infectious diseases.
Although Pastor was already 58 years old at that time, it was precisely now that the period of his most outstanding discoveries began. The discovery of a vaccine against chicken cholera was followed by experiments on anthrax. Anthrax - a severe, often fatal disease of livestock, sometimes affecting humans as well - at that time brought enormous losses to livestock farms. Armed with his brilliant method of weakening the causative agents of a contagious disease and using them for vaccinations, Pasteur, after numerous laboratory experiments began to develop a vaccine against anthrax. After hard and painstaking work, Pasteur managed to find the conditions under which anthrax microbes lose their toxicity, and to prepare a vaccine. It was tested in the famous public experiment on the Poulier-le-Fort farm in the spring of 1881. Having received 60 sheep and cows at his disposal, Pasteur made several preliminary vaccinations for half of them and then, in the presence of numerous spectators, infected both the vaccinated and the unvaccinated. animals with anthrax in its deadliest form. All those present were warned that in 48 hours thirty animals would die, and the remaining half - previously vaccinated animals - would remain safe and sound. The prediction came true literally. The following picture presented itself to those gathered in Pouliers-le-Fort: 22 sheep lay dead, 2 died in front of the audience, and the remaining 6 animals died by the end of the day; 30 vaccinated remained alive and well.
The effect of this experience was exceptional. Newspapers around the world noted the unprecedented success of Pasteur. The method of inoculation developed by him received full recognition.
Following his victory over anthrax, Pasteur went ahead along the intended path. Now he took on a new, very difficult task - to find the germ of rabies. The mere name of this disease, always fatal to man, was terrifying. Medicine did not know any means of combating rabies, and it was well known; if a person is bitten by a rabid wolf or a dog and he falls ill, then there is no salvation, the bitten must die in severe torment of hydrophobia.
A long and intense search this time did not give the usual result. The rabies microbe could not be found either in sick people or in sick animals. Now we know that the causative agent of this disease cannot be seen under a microscope, it belongs to the category of so-called filterable viruses and can only be detected special methods studies unknown in Pasteur's time. All the more, Pasteur's gift of foresight seems great: having not found a microbe that causes hydrophobia, he did not stop his research and, through the most ingenious experiments and logical conclusions, discovered a way to combat rabies.
When studying dogs with rabies, it was found that the receptacle of the infection is the nervous system - the brain and spinal cord. If you take pieces of nervous tissue, crush them and then use a syringe to inject a healthy animal under the cranial bone, then typical rabies breaks down in it. Thus, it is possible to induce disease at the will of the experimenter. Following further his principle of weakening the infectious principle with its subsequent use to create immunity, Pastor found a way to weaken the terrible poison of rabies. His talented assistants Roux and Chamberlain removed the spinal cord from a rabbit that had died of rabies and then dried it for 14 days in a glass jar. So 14 varieties of dried rabies poison were prepared, with different strengths, ranging from almost harmless to poison of one day's drying, capable of killing an unvaccinated dog. But if these 14 doses are injected successively into dogs, starting from the weakest, and after that the vaccinated animals are infected with the deadly poison of rabies, the vaccinated dogs will not get sick.
After careful control of these experiments, the commission of the French Academy of Sciences came to the following conclusion: "if a dog is immunized with gradually increasing doses of the poisonous spinal cord of rabid rabbits, it can never get sick with rabies."
Victory seemed to be in Pasteur's hands, but there was still another question to be settled. Is it possible with such vaccinations to save from the disease not only before the penetration of the infection, but also after the bite of a rabid animal? In other words, is it possible not only to prevent the disease, but also to cure it? And this issue was soon resolved. The poison of rabies acts slowly. From the moment of the bite to the appearance of the first signs of the disease, it takes several weeks, and sometimes months. Therefore, it turned out to be possible to follow this deadly poison, slowly moving towards the central nervous system, to send a poison weakened, but with a faster effect. He is ahead of the strong poison and prepares nervous system making the body invulnerable.
This bold and brilliant idea of Pasteur was brilliantly realized and confirmed by numerous experiments. But experiments on animals, no matter how good they are, are still not enough to judge the benefits of vaccinations for humans. And on July 4, 1885, the first injection of a weakened poison of rabies into a person was made. It was nine-year-old Josef Meister, an unfortunate boy who had been severely bitten by a mad dog. Day after day, the first patient received all 14 shots. Vaccinations saved the boy from a fatal disease.
At this time, Pasteur was 63 years old. This was the pinnacle of his scientific activity and fame; His name became the property of all mankind.
Pasteur's services to science are great, and it is impossible to convey in a brief essay the full significance of his discoveries. Microbiology, of which he is rightfully considered the founder, has now developed into a vast independent branch. natural sciences playing exclusively important role not only in medicine, but also in veterinary medicine and agriculture.
In medicine, Pasteur's work, as we have already seen, is of great importance for the development of surgery and for the fight against infectious diseases. Modern immunology, that is, the doctrine of immunity to infectious diseases, is entirely based on the method of immunization discovered by Pasteur: the use of pathogens weakened in their toxicity for vaccinations that protect against infection. The method of protection against rabies developed by Pasteur saved mankind from the horrors of this terrible disease. All over the world, special institutions are organized, the so-called Pasteur stations, where they prepare material for vaccination against rabies. It is interesting to recall that the second Pasteur station in the world, after the one in Paris, was organized in Russia by Russian scientists I. I. Mechnikov and N. F. Gamaleya.
The importance of Pasteur in medicine is also great because he widely introduced into the study medical issues experimental (experimental) research method. This method has armed scientists with that exact knowledge of disease processes, which was completely absent in the pre-Pasterian era, and has brought so many brilliant successes to the present time.
half a century scientific activity Pasteur, full of hard work and endless searches, passed under the banner of the creative power of thought and the amazing ability to turn her ideas into undeniably proven facts through a long series of experiments. He taught his students: “Don't say anything that you can't prove simply and beyond doubt. Bow before the spirit of criticism. By itself, it does not reveal new ideas or inspire great deeds. But without it, nothing is solid. Behind him always remains the last word. This demand, which I present to you, and you will present to your students, is the heaviest one can be presented to a researcher who is making discoveries. To be sure that you have discovered an important scientific fact, to burn with a feverish desire to notify the whole world about it and to ask yourself for days, weeks, sometimes years; to enter into a struggle with oneself, to exert all one's strength in order to destroy the fruits of one's own labors and not to proclaim the result obtained until one has tried all the hypotheses that contradict it - yes, this is a difficult feat. But, on the other hand, when after so much effort you achieve complete certainty, you experience one of higher joys which are only accessible to the human soul.
Pastor's life is a perfect confirmation of his words. Devotion to science and selflessness were excellent traits of his character. “In the midst of one of his works,” recalls K. A. Timiryazev, “as always, absorbing all of his physical forces, since intensified mental work was usually complicated by insomnia, the doctor who treated him, seeing that all exhortations were in vain, was forced to threaten him with the words: “You are threatened, perhaps by death, and a second blow, probably.” Pasteur thought for a moment and calmly replied: “I cannot interrupt my work. I already foresee its end: come what may, I will fulfill my duty.
Pasteur died on September 23, 1895 at the age of 73. Since then, 50 years have passed. Over the years, natural science has gone far ahead in its development. And in the progress of science, which we are witnessing, the unfading glory of the name of Luke Pasteur illuminates the way for new searches and new discoveries.
Louis Pasteur was born in France, the town of Dol, December 27, 1822 in the family of a tanner. He was educated at Arbois College, where he became a teacher's assistant. Later he worked as a junior teacher in Besançon. On the advice of his teachers, in 1843 he entered the Paris Higher Normal School, from which he graduated in 1847. He was a professor of physics at the Dijon Lyceum (1847-1848), after that he was a professor of chemistry at Strasbourg (1849-1854) and Lille (since 1854) universities. In 1856, Louis Pasteur received the position of director of studies at the Higher Normal School, where he reformed education.
As a student, Pasteur made the first discovery in the field of chemistry. In 1848, while studying tartaric acid crystals, he concluded that they were composed of asymmetric molecules. Dividing the crystals into two parts, he found that they were optical antipodes. This discovery formed the basis of a new direction in chemistry - stereochemistry.
Studying the process of fermentation, in 1857 Louis Pasteur proved its biological nature. In his research, he came to the conclusion that fermentation is obtained as a result of the action of microorganisms - bacteria deprived of oxygen. In 1861, Pasteur proposed a method of preserving liquid products by heat treatment, later called "pasteurization".
Since 1865, Louis Pasteur began to study the causes of silkworm disease in the south of France. scientist found effective methods fight this disease and saved sericulture. And since 1876, Pasteur devoted himself entirely to immunology. He studied diseases such as anthrax, puerperal fever, cholera, rabies and others. In the process of research, he found that diseases are caused by a certain kind of pathogens. In 1881 he developed a vaccine against anthrax, and in 1885 against rabies. Thus, he made the first major step in the history of vaccination.
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The founder of microbiology and immunology, Louis Pasteur was born in the city of Dole (commune of the department of Jura, France) on December 27, 1822. The young man received his education first at the Arbois College, and then at the Saint-Louis Lyceum in Paris. During this time, he was also a lecturer at the Sorbonne.
In 1843, Pasteur became a student of the Higher Normal School, enrolling there in the department of natural sciences. After graduating from it, he defended his doctoral dissertation in physics, and then in chemistry and with the rank of professor began to teach at best universities countries (Dijon, Strasbourg and Lille universities).
At this time, Pasteur wrote fundamental works that initiated the development of stereochemistry. Then in 1857 the scientist returned to his native educational institution, becoming deans of the Faculty of Natural Sciences.
In the same year, he began to study fermentation and discovered the biological nature of this process. As a result, Pasteur proposed a new way of preserving food products through their heat treatment, called pasteurization.
The scientist conducted his further research in the field of immunology. It was he who became the creator of the first vaccine against anthrax (1881), and four years later - against rabies.
Despite the fact that the vaccinations made by the professor's scientific team worked, this still did not prevent the opponents of the scientist's activities from attacking him with reproaches of charlatanism and the spread of diseases. Under such conditions, Pasteur, whose health was undermined by a series of strokes that began as early as 1968, could no longer work. Having retired, he soon died on September 28, 1895.
Discoveries only come to those who are prepared to understand them.(Louis Pasteur) Pasteur, a French chemist and microbiologist, was the first to successfully use a vaccine against such terrible diseases as anthrax, cholera and rabies. With his work on the study of fermentation, Pasteur saved the producers of beer, wine and silk in France and in other countries; He also invented pasteurization.
Louis Pasteur was born December 27, 1822. He was the son of a retired French soldier, the owner of a small tannery in the town of Dole. Pasteur successfully completed his studies, first at a college in Arbois, and then in Besançon. After graduating here with a bachelor's degree, he entered the Higher Normal School in 1843. Louis was particularly interested in chemistry and physics.
After graduating from school in 1847, Pasteur passed the exams for the title of assistant professor of physical sciences. And a year later he defended his doctoral dissertation. Then Pasteur had already gained fame for his research in the field of crystal structure. He discovered the reason for the unequal influence of a beam of polarized light on the crystals of organic substances.
Also in 1848, Pasteur became associate professor of physics at Dijon. In three months he takes new position associate professor of chemistry in Strasbourg. Pasteur took an active part in the revolution of 1848.
In 1854 he was appointed dean of the Faculty of Natural Sciences in Lille. Pasteur noticed that asymmetric crystals are found in substances formed during fermentation. In 1857 Pasteur proved that fermentation is not chemical process, as it was then customary to think, but a biological phenomenon, which is the result of the vital activity of microscopic organisms - yeast fungi.
Pasteur found that there are organisms that can live without oxygen. They are called anaerobic. Their representatives are microbes that cause butyric acid fermentation. The reproduction of such microbes causes rancidity of wine and beer.
In 1857 Pasteur returned to Paris as vice-principal of the Higher Normal School. In 1862 he was elected a member of the "institute" in the department of mineralogy, and a few years later the permanent secretary of the institute. In 1867-1876 he held the chair of chemistry at the Faculty of Paris.
In 1864, he began to study the issue of the occurrence of wine diseases. The result of his research was a monograph in which Pasteur showed that wine diseases are caused by various microorganisms, and each disease has a specific pathogen. To destroy the harmful "organized enzymes" he suggested heating the wine at a temperature of 50-60 degrees. This method is called pasteurization.
In 1874, the Chamber of Deputies, in recognition of outstanding services to his homeland, awarded him a lifetime pension of 12,000 francs, increased in 1883 to 26,000 francs. In 1881 Pasteur was elected a member of the French Academy.
Starting with unraveling the "diseases" of wine and beer, the scientist later life devoted to the study of microorganisms and the search for means of combating pathogens of dangerous contagious diseases of animals and humans.
Pasteur's works revealed the fallacy of the view that was widespread in medicine of that time, according to which any diseases arise either inside the body or under the influence of spoiled air ("miasma"). Pasteur showed that diseases that are called contagious can only occur as a result of infection, i.e., penetration into the body from external environment microbes.
In 1880, Pasteur found a way to prevent infectious diseases by introducing weakened pathogens, which turned out to be applicable to many infectious diseases.
But before the vaccination method was fully accepted, Pasteur had to endure a difficult struggle. To prove the correctness of his discovery, in 1881 Pasteur made a massive public experiment. He injected dozens of sheep and cows with anthrax microbes. Half of the experimental animals Pasteur pre-injected his vaccine. On the second day, all unvaccinated animals died from anthrax, and all vaccinated animals did not get sick and remained alive. This experience, which took place in front of numerous witnesses, was a triumph for the scientist.
Pasteur developed a method of inoculation against rabies, using specially dried brains of rabbits infected with rabies. On July 6, 1885, he successfully tested a vaccine on a human for the first time.
In 1889, Pasteur resigned from all duties in order to devote himself to the organization and management of the institute named after him. The Royal Society of London awarded him two gold medals in 1856 and 1874; The French Academy of Sciences awarded him a prize for his work on the question of spontaneous generation.
In 1892, the seventieth anniversary of the birth of the scientist was solemnly celebrated, and on September 28, 1895, Pasteur died in Vildeneuf-Letan, near Paris.
“The French bacteriologist Louis Pasteur was studying the culture of the smallpox bacterium in his laboratory. Suddenly, a stranger appeared to him and introduced himself as a second of a nobleman, who thought that the scientist had insulted him. The nobleman demanded satisfaction. Pasteur listened to the messenger and said: “Since they call me, I have the right choose a weapon. Here are two flasks; smallpox bacteria in one, pure water in the other. If the person who sent you agrees to drink one of them, I will drink another. "The duel did not take place."