As noted by John Wesley Work in his book American Negro Songs and Spirituals, African-American songs often retain forms that originated in African tribal customs. "Go Down, Moses" belongs to the largest group, a class of spirituals that use the African "call-and-response chant form." Mr. Work describes it as "interesting as well as distinctive. Its feature is a melodic fragment sung repeatedly by the chorus as an answer to the challenging lines of the leader which usually change." In this version the chorus, "Let my people go," repeats every second and fourth line in stanzas two and three and as the last line in stanza one. It is meant to be sung by a group in answer to an individual voice that sings the first and third lines of each stanza. This repetition not only provides structure for the song, it also enables the lyrics to be easily...