produced by sparks, the latter image is a diagram based on the first, I believe.
Last up is the Phonodeik an instrument designed by Dayton Miller
that allows the photography over time of complex sound waves. It
reminds me very much of the earlier Phonautograph but with a
I have allot more stuff to include on this subject including cymatics and optical sound experiments which I left out to cut down the size of this post, but if you have any interesting links I always welcome tips in the comments