When the Houston Ballet opens its season on Sept. 6, with "The Little Mermaid", there will be an unusual instrument in the orchestra pit. The theremin, which famed music critic Harold C. Schonberg ...

As Wikipedia describes the theremin’s control: The instrument’s controlling section usually consists of two metal antennas that sense the relative position of the thereminist’s hands and control ...

Even if you don’t know what a theremin is, you’ve almost certainly heard it. The futuristic instrument — played by carefully gesturing with your hands in the air — has been a staple of old sci-fi ...