Adolf Wölfli. Wow. Must admit I'd never known his work until just now, and I am floored.
Gelesen und vertont (Adolf Wölfli - Recited And Set To Music) *1978
Adolph Wölfli: The Heavenly Ladder / Analysis of the Musical Cryptograms, by Baudoin De Jaer. 2011 release on Sub Rosa, wherein violinist De Jaer masterfully interprets Wölfli's wild & cryptic musical notations. Thanks to "Unknown" for the tip.