I find this kind of thing very interesting...It would make a great news story for RockLibrary.
In 1860 a scientist in France figured out how to create a visual interpretation of sound and because a patent was filed in Paris a researcher was able to find and examine the images that just happened to be dated.
On March 1, 2008 David Giovanni of First Sounds, a US collaborative aimed at finding and preserving lost early recordings, received a package from the archive at the French Academy of Sciences in Paris that contained a sound recording made in France in 1860, 17 years before Thomas Edison recorded 'Mary had a little lamb'.
The 10-second recording is of a person singing a snippet of a French folk song, 'Au clair de la lune', and was recorded on April 9, 1860 by Parisian inventor Édouard-Léon Scott de Martinville using piece of equipment he called a "phonautograph" that scratched sound waves onto a sheet of paper blackened by the soot of an oil lamp.
Using advanced imaging technology scientists at the Lawrence Berkeley National Laboratory in Berkeley, California were able to create digital images that captured “grooves” that could then be played by a computer with a virtual stylus.
Interestingly enough the recording was never meant to be played only studied visually as an interpretation of sound.
The recording and findings are being presented by to the Association for Recorded Sound Collections conference at Stanford University this week by the man who found it David Giovanni.
Listen to the oldest known recording.