Louis Pasteur

Louis Pasteur was born December 7, 1822, in Paris. He was the son of a tanner and grew up in the small town of Arbois.

In 1847, he received his Ph.D in physics and chemistry at the Ecole Normale in Paris. Becoming an assistant to one of his teachers, he began research that led to a discovery. He found that when a beam of polarized light passed through a solution of naturally produced organic nutrients, the light was bent to the right or left. Whereas if the beam passed through a solution of artifically synthesized organic nutrients, the beam didn't bend. Pasteur found that when chemists synthesized an organic compound, its optical effects are cancelled.

After teaching at Dijon & Strasbourg for several years, Pasteur moved to the University of Lille, where he was named Professor of Chemistry and Dean of the newly founded Faculty of Sciences in 1854. He immediately devoted himself to research on the process of fermentation. In the 1860's, a debate was rising - could beetles, maggots, eels, mice, etc. appear spontaneously? His research and experience with fermentation led him to believe that nothing appeared spontaneously. He produced a set of two experiments for himself to see this.

First, he drew the juice out of grapes using a heated hypodermic needle and placed it into a sealed jar. The juice didn't ferment, but juice that had dust from the grapes' surface did ferment - it didn't appear spontaneously. In another experiment, he drew the juice out of the grapes the same way as before. Then, he put the juice in a flask with a long, thin neck. He heated the neck so he could bend it into an "s" shape before sealing it. Nothing grew in the flask. Next, he snapped off the seal. Dust did fall into the open end, but it didn't touch the juice. He tilted the flask so the juice touched the dust. The juice now fermented. Pasteur had shown that it was the dust - not the air - that caused fermentation.

In 1865, Pasteur was called in by the French Department of Agriculture to investigate a disease that was devastating silkworms. Pasteur taught the silk farmers to tell if the worms had the diseases - pebrine and flacherie. During his research, he found that healthy worms that fed on leaves touched by sick worms caught the disease. All together, Pasteur was led to believe that disease was caused by micro-organisms.

Later on, Pasteur was studying the kind of cholera that affected chickens. He identified the bacteria and was growing it into a culture. If he injected it into a chicken, it'd die within 48 hours. He went away from the lab for three weeks one summer and returned to find that his cultures of cholera couldn't kill the chickens. He and his colleagues were disappointed - maybe these bacteria weren't the killers after all? So, he made a new batch of bugs and injected it into the chickens. The chickens with the old bugs were unaffected, but the ones that received the new batch died. Pasteur had realized tha the had come up to the same experiment outcome as Edward Jenner. The bugs had given the chicken immunity! He had made a vaccine for the disease.

Pasteur spent the rest of his life working on the cause of rabies. After experimenting with the saliva of animals suffering from this disease, he concluded it came from the nerve centers of the body. When an extract from the spinal column of a rabid dog was injected into the bodies of healthy animals, symptoms of rabies were produced. By studying the tissues of animals, particularly rabbits, he was able to develop a subdued form of the virus that could be used for vaccination.

In 1885, a young boy and his mother arrived at Pasteur's laboratory; the boy had been bitten by a rabid dog. Pasteur was urged to use his new method. After the ten day treatment, the boy recovered and remained healthy. His research on rabies resulted, in 1888, in the founding of a special institute for treatment of the disease in Paris. It was run by Pasteur until he died.

When Louis Pasteur died September 28, 1895, the world was a safer place.