The power of a musical instrument: Franklin, the Mozarts, Mesmer, and the glass armonica.

In 1761 Benjamin Franklin invented the armonica (often referred to as the glass harmonica), an instrument designed to simplify the playing of the musical glasses. The instrument immediately became popular and inspired compositions by Wolfgang Mozart, who had the opportunity to hear and play one at the house of Franz Anton Mesmer. Armonica music was used by Mesmer in his séances, because he felt it could promote healing by propagating a mystical fluid that he called animal magnetism through the body. After Mesmer's theories were debunked by a highly respected panel of scientists, the armonica fell out of vogue. Because Franklin was on the panel that examined the discredited mesmerism, he indirectly contributed to his own invention's demise.