28 sept. 1928 - 28 September 1928: Fleming accidentally discovered
penicillin because he had left his laboratory for a month
in august and upon returning, he found that one of his
stacked-up cultures was contaminated with a fungus
and all the colonies of staphylococci immediately
surrounding the fungus were destroyed. He analyzed
this fungus and found out that he had discovered the first
antibiotic or "bacteria killer".