If you have ever watched an old horror movie or sci-fi movie, you may have heard eerie sounds that seemed to float around in the high register. Examples are found in The Day the Earth Stood Still, Spellbound, and Lost Weekend. The instrument used to make those sounds is called a Theremin, invented in 1919 by a Russian physicist named Leon Theremin (changed from Lev Termem). It was a very unusual instrument in that the performer never touches the instrument while playing. It consists ...