He also reasoned that there was some special internal arrangement to the molecules of such a compound that twisted the light—an “asymmetric” arrangement.
This hypothesis holds an important place in the early history of structural chemistry—the field of chemistry that studies the three-dimensional characteristics of molecules.
Months into the experiments, Pasteur let cultures of fowl cholera stand idle while he went on vacation.
When he returned and the same procedure was attempted, the chickens did not become diseased as before.
Spurred by his mentors’ encouragement, he undertook rigorous studies to compensate for his academic shortcomings in order to prepare for the École Normale Supérieure, the famous teachers’ college in Paris.
He earned his master’s degree there in 1845 and his doctorate in 1847.
In 1857 Pasteur returned to the École Normale as director of scientific studies.
In the modest laboratory that he was permitted to establish there, he continued his study of fermentation and fought long, hard battles against the theory of spontaneous generation.
The process was later extended to all sorts of other spoilable substances, such as milk.
At the same time Pasteur began his fermentation studies, he adopted a related view on the cause of diseases.