I finally took the time to scan these torn-out pages from an old Time Life book (1981) that I found water damaged here at the house while purging. It is a really great read that characterizes and even demystifies the qualities that distinguishes electronic music from other forms.
Technically isn't the majority of music these days "electronic music" by definition given the reliance of technology in 99% of the process? Maybe...
The 7-pages cover a lot of territory and offer in depth information from the introduction of the phonograph and magnetic tape in music, early field-recordings and musique concrète to the structure and pioneers of modern synthesizers and advice in making your own tape-loops.