Analogue audio - Cylinders and 78 rpm

"Phonograph cylinders were the earliest commercial medium for recording and reproducing sound. Commonly known simply as "records" in their era of greatest popularity (c. 1888–1915), these cylinder shaped objects had an audio recording engraved on the outside surface which could be reproduced when the cylinder was played on a mechanical phonograph. The competing disc-shaped gramophone record system triumphed in the market place to become the dominant commercial audio medium in the 1910s, and commercial mass production of phonograph cylinders ended in 1929" from http://en.wikipedia.org/wiki/Phonograph_cylinder

"Early disc recordings were produced in a variety of speeds ranging from 60 to 130 rpm, and a variety of sizes. From 1900, the two leading manufacturers of flat records were Columbia, which used 80 rpm as its speed, and Victor, which used 76.59 rpm. Since one company's records were playable on the other's machines, the standard speed became 78 rpm, which is around the average speed between the two. By 1925, the speed of the record became standardised at a nominal value of 78 rpm."

http://en.wikipedia.org/wiki/Gramophone_record

You can listen old cylinders and 78 rpms at http://www.archive.org/details/78rpm Internet Archive has a huge collection, quite interesting for researches on the modern music history.
rpm = revolutions per minute