April 21, 1904 – Controversial baseball legend Ty Cobb begins his career playing for the Augusta, Georgia team of the South Atlantic League. He winds up in Detroit and spends 22 seasons with the Tigers setting 90 big league records, several of which he still holds.
April 22, 1970 – An estimated 20 million people turn out for locally-organized environmental educational events promoted by Wisconsin Senator Gaylord Nelson. Nelson was trying to call attention to the inaction of Congress on environmental issues and inaugurated the very first “Earth Day”.
April 26, 1954 – The Salk polio vaccine field trials, involving 1.8 million children, begin at the Franklin Sherman Elementary School in McLean, Virginia. Children in the United States, Canada and Finland participated. One year later, researchers announced the vaccine was safe and effective and it quickly became a standard part of childhood immunizations.
April 26, 1994 – Multiracial elections were held for the first time in the history of South Africa. Anti-Apartheid leader Nelson Mandela was elected President.