The South African activist and former president Nelson Mandela (1918-2013) helped bring an end to apartheid and has been a global advocate for human rights.<span>A member of the African National Congress party beginning in the 1940s, he was a leader of both peaceful protests and armed resistance against the white minority’s oppressive regime in a racially divided South Africa.
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The conceiver of one of mankind's coolest ideas for boundless clean energy died last week. He was 90 and first published his ideas in 1968, a year before NASA put a man on the moon. In its December 1972 issue, Popular Science described engineer Peter Glaser's proposal:
The 15th president is James Buchanan
