Happy Birthday, Louis!

Born today in 1822 in Dole, France - Louis Pasteur.

If you're like me, you think of pasteurized milk, and maybe beer ... but the man was a workhorse of science. Louis Pasteur brought about a veritable revolution in the 19th-century scientific method. By abandoning his laboratory and by tackling the agents of disease in their natural environments, he was able through his investigations to supply the complete solution to a given question, not only identifying the agent responsible for a disease but also indicating the remedy.

When in 1881 he had perfected a technique for reducing the virulence of various disease-producing microorganisms, he succeeded in vaccinating a herd of sheep against the disease known as anthrax. Likewise, he was able to protect fowl from chicken cholera, for he had observed that once animals stricken with certain diseases had recovered they were later immune to a fresh attack. Thus, by isolating the germ of the disease and by cultivating an attenuated, or weakened, form of the germ and inoculating fowl with the culture, he could immunize the animals against the malady. In this he was following the example of the English physician Edward Jenner in his method for vaccinating animals against cowpox. On April 27, 1882, Pasteur was elected a member of the Académie Française, at which point he undertook research that proved to be the most spectacular of all—the preventive treatment of rabies. Having detected the rabies virus by its effects on the nervous system and attenuated its virulence, he applied his procedure to man; on July 6, 1885, he saved the life of a nine-year-old boy, Joseph Meister, who had been bitten by a rabid dog.

Among his other discoveries - the theory of molecular asymmetry, showing that the biological properties of chemical substances depend not only on the nature of the atoms constituting their molecules but also on the manner in which these atoms are arranged in space. By means of simple and precise experiments, including the filtration of air and the exposure of unfermented liquids to the air of the high Alps, he proved that food decomposes when placed in contact with germs present in the air, which cause its putrefaction, and that it does not undergo transformation or putrefy in such a way as to spontaneously generate new organisms within itself.

He showed that milk could be soured by injecting a number of organisms from buttermilk or beer but could be kept unchanged if such organisms were excluded. After laying the theoretical groundwork, Pasteur proceeded to apply his findings to the study of vinegar and wine, two commodities of great importance in the economy of France; his pasteurization process, the destruction of harmful germs by heat, made it possible to produce, preserve, and transport these products without their undergoing deterioration. In 1870 Pasteur devoted himself to the problem of beer. Following an investigation conducted both in France and among the brewers in London, he devised, as he had done for vinegar and wine, a procedure for manufacturing beer that would prevent its deterioration with time. British exporters, whose ships had to sail entirely around the African continent, were thus able to send British beer as far as India without fear of its deteriorating.

In 1865 he undertook a government mission to investigate the diseases of the silkworm, which were about to put an end to the production of silk at a time when it comprised a major section of France's economy. To carry out the investigation, he moved to the south of France, the centre of silkworm breeding. Three years later he announced that he had isolated the bacilli of two distinct diseases and had found methods of preventing contagion and of detecting diseased stock.

In 1854 Pasteur became dean of the new science faculty at the University of Lille, where he initiated a highly modern educational concept: by instituting evening classes for the many young workmen of the industrial city, conducting his regular students around large factories in the area, and organizing supervised practical courses, he demonstrated the relationship that he believed should exist between theory and practice, between university and industry. A skillful experimenter endowed with great curiosity and a remarkable gift of observation, Pasteur devoted himself with immense enthusiasm to science and its applications to medicine, agriculture, and industry.

"Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world. Science is the highest personification of the nation because that nation will remain the first which carries the furthest the works of thought and intelligence."

info and many sentences from: "Pasteur, Louis." Encyclopædia Britannica. 2006. Encyclopædia Britannica Online. 27 Dec. 2006 < http://www.britannica.com/eb/article-12562 >.