King Oliver's Creole Jazz Band in Chicago in 1923: Louis Armstrong is kneeling, from left to right behind him are Honore Dutrey, Baby Dodds, King Oliver, Lil Hardin, Bill Johnson and Johnny Dodds.
Frank Driggs Collection/Getty Images
A 16-inch lacquer disc, a format used in the 1930s, from the collection of the Library of Congress. Most of the lacquer, the part of the disc where the sound was etched, has been lost to decay.
Abby Brack/Library of Congress