Phonograph cylinder
From Just Solve the File Format Problem
Phonograph cylinders were introduced by Thomas Edison in the late 1800s as the first system for the distribution of recorded sound. It later had a "format war" with disc-shaped gramophone records, which ended with the discs winning out.
As the contents of most phonograph cylinders are in the public domain now due to age, many have been digitized into computer sound files which can be freely downloaded on the Internet.
