Harriet Tubman is perhaps the most well-known of all the Underground Railroad's "conductors." During a ten-year span she made 19 trips into the South and escorted over 300 slaves to freedom.

“I had to draw a line, because I can’t swim,” she says. Eventually she became a teacher’s aide. The schools didn’t teach much about Tubman then. One year, Manokey remembers, the teacher in her ...