(1852) French chemist Henri Moissan is born. He studied metabolism in plants and also won the 1906 Nobel Prize in Chemistry for isolating fluorine.
(1895) French chemist and microbiologist Louis Pasteur passes away. He is remembered for his discoveries of the principles of vaccination, microbial fermentation and pasteurization.
(1928) Sir Alexander Fleming discovered penicillin as a bacteria-killing mold growing in his laboratory.