Chapter 6 is about the phonograph and its role in sharing information. Edison invented the first phonograph in 1877. His machine merged the telephone’s ability to receive sound and the telegraph’s ability to write. It comprised a mouthpiece that gathered soundwaves and a diaphragm that recorded and played back sound. Edison’s first machine held less than a minute of poor-quality sound. However, he and his machinist improved the sound quality before presenting their invention at the offices of Scientific American, the country’s premier source of science news. With the phonograph, Edison created a new way to represent information. Sound was no longer ephemeral. It could be recorded and replayed.

Edison’s invention had a profound impact on music. Before the phonograph, live performances were the only way that people—at least, those who had the time and means to attend concerts—could enjoy music. The phonograph democratized music by bringing it into people’s homes. A music industry soon emerged, selling 26 million records by 1906. As Ramirez observes, recordings spurred cross-fertilization between musical genres—such as jazz, blues, and rock and roll—even as musicians themselves remained physically separate and segregated by race politics: “Blacks and whites did not socialize, but phonograph records crossed these racial divides, enabling white and black musicians to hear and borrow styles from one another” (154).