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Peter Waldo >The French religious leader Peter Waldo (active 1170-1184) believed in >voluntary poverty and religious simplicity. His followers were considered >heretics by the Church. Some men's personal lives are eclipsed by the movements they start. Peter Waldo was such a man.
Alexandre Yersin Swiss-born French bacteriologist and one of the discoverers of the bubonic plague bacillus, Pasteurella pestis, now called Yersinia pestis. Yersin studied medicine at the universities of Marburg and Paris and bacteriology with Émile Roux in Paris and Robert Koch in Berlin. In 1888
Cleveland Abbe, American astronomer, meteorologist, and weather forecaster who assisted in the development and growth of the U.S. Weather Bureau, later renamed the National Weather Service.
Chester F. Carlson was an American physicist who was the inventor of xerography, an electrostatic dry-copying process that found applications ranging from office copying to reproducing out-of-print books. By age 14 Carlson was supporting his invalid parents, yet he managed to earn a college degree