By Lucas Shepard
Alexander Fleming accidentally invented penicillin. In 1928 Alexander fleming went on a vacation for two weeks. When he got back he had noticed that one of his dishes had a mold on it. He observed that existing bacteria did not grow near the mold and found it staving off microorganisms. 13 years after that, three men named Howard Florey, Norman Heatley, Andrew Moyer Switched the type of mold to one that grew better and could test in the medical.