How did John and Alan Lomax document Mississippi Delta blues at Parchman Farm?

Folk music scholars John Lomax and his son Alan Lomax documented Mississippi Delta blues through field recordings conducted at the Mississippi State Penitentiary, commonly known as Parchman Farm, in Sunflower county, Mississippi.1

These efforts were part of their broader work touring prisons across the American Deep South to record folk-song performances for the Library of Congress Archive of American Song. By visiting these institutions, the Lomaxes were able to capture traditional music that might otherwise have gone undocumented, preserving the voices and styles of musicians who were often excluded from the commercial recording industry of the time.21