Selling 1 million copies a year for over 100 years, McGuffey's Readers were the mainstay of pubic education in America. Millions of school children read them, making them some of the most influential textbooks of all time. They were written by William McGuffey, who died this day, May 4, 1873. He was a professor at the University of Virginia, president of Ohio University, and formed one of the nation's first teachers' associations. A lesson in McGuffey's Fifth Eclectic Reader stated: "How powerless conscience would become without the belief of a God."