Read the original article here: http://oddstrument.com/2008/05/08/banned-musical-instrument-causes-insanity/

From [oddstruments]:
"The glass armonica’s ghostly notes will cause insanity in its musicians and listeners! At least this is what was thought to be true in the 18th century. People were frightened by the armonica’s sound due to it’s strange interactions with the human brain and ears (more on this later). Benjamin Franklin invented the glass armonica (above) in 1761 after being profoundly moved by the sounds of the glass harp... The glass armonica’s ethereal notes were said to cause insanity, depression, and marital problems."

"The glass armonica’s sound is perceived by human ears differently than other instruments because its range is between 1,000 and 4,000 hertz. When sounds are below 4,000 hertz, the human brain compares “phase differences” between the left and right ears to triangulate the origin of the sound rather than comparing volumes. This causes hearing disorientation and a “not quite sure” feeling about where the sound is coming from."