Although it was championed by the likes of Mozart and Benjamin Franklin, in its heyday the glass harmonica was also the object of considerable trepidation.
In the 18th century music was regarded by some as a form of nervous stimulation that could cause a range of maladies, and the glass harmonica was considered especially dangerous.
The glass harmonica player and composer Karl Leopold Röllig stated that the instrument could “make women faint, send a dog into convulsions, make a sleeping girl wake screaming through a chord of the diminished seventh, and even cause the death of one very young”, and physicians warned of possible ill effects including muscle tremors, prolonged shaking of the nerves, fainting, cramps, swelling, paralysis, and seeing ghosts.
This according to Bad vibrations: The history of the idea of music as cause of disease by James Kennaway (Farnham: Ashgate, 2012). Below, Thomas Bloch threatens you with Mozart’s adagio, K.617.
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