Multi-instrumentalist, vocalist, and folk song collector Frank Hamilton has played a seminal role in the evolution of American folk music. A co-founder of the Old Town School of Music in Chicago in 1957, Hamilton taught the future leader of the Byrds, Roger McGuinn, to play guitar and banjo. Accompanied by his wife, Mary, Hamilton's interpretations brought a new sensibility to songs of America's past. His stint with the Weavers, as replacement for Erik Darling, who had replaced Pete Seeger, lasted little more than a year -- 1962 to 1963 -- but his contributions remained essent...