Stavin' Chain playing guitar and singing the ballad "Batson" accompanied by a musician on violin, Lafayette, Louisiana (1934). Courtesy of the Library of Congress.
In addition to the developing synthesis between black folksong and European-American narrative patterns found in minstrel songs, another trend marked a watershed moment in the development of the blues. The rise of mail order companies such as Sears, Roebuck and Co. made guitars inexpensive and readily available, and the dry-sounding, staccato yelp of the banjo was quickly traded for the "vocal-like" and sustained whine of the six-stringed guitar, an instrument whose "new techniques were more in keeping with the new century" (Oliver). A variety of instruments, including fiddles, horns—and, more simply, jugs, saws, and washboards—remained in common use, but the emergence of the guitar set the stage for the genre's signature sound, that of the lonesome songster as portrayed by the likes of "Blind" Blake and Robert Johnson.
Ely, Melvin Patrick. Oliver, Paul. "Blues." In Africana: The Encyclopedia of the African and African American Experience, 2nd ed., edited by Kwame Anthony Appiah and Henry Louis Gates Jr. New York: Oxford University Press, 1999.