What's BS about a musical instrument? There's a wonderful book that the Boy gave me last Christmas, Harmonious Triads by Prof. Myles Jackson, that explores the late 18th Century popularity of these instruments (among very much more excellent stuff). I've heard them on the radio, and even seen one in a glass case in a museum, but never heard one played live. It's not something you could really take to a session.

The ethereal sound was supposed to arouse profound passions, particularly in women, and the instrument became associated with experiments in electricity, hypnotism, breathing of gases and suchlike radical experiments, and fell out of popularity as the Enlightenment gave way to the Reaction.