1534 – Jacques Cartier begins the voyage during which he discovers Canada and Labrador
1862 – Louis Pasteur and Claude Bernard complete the first pasteurization tests
1902 – Pierre and Marie Curie refine radium chloride
1926 – Western Electric and Warner Bros. announce Vitaphone, a process to add sound to film
1972 – Apollo 16 lands on the Moon

Joan Miró i Ferrà (April 20, 1893 – December 25, 1983)

420 (cannabis culture)