July 6, 1886: French scientist Louis Pasteur (also famous for developing the process of pasteurization of milk) successfully tested his rabies vaccine on a 9-year-old boy who had been bitten by a rabid dog, thereby saving him from certain death.
July 6, 1947: In the Soviet Union, production began on the AK-47 assault rifle (also known as the Kalashnikov, after the man who created it).