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Amazing inventor Athanasius Kircher designed this cat piano in in the 17th century. Kitties with differently-pitched voices were placed in the pens and then "triggered" to meow with a sharp poke in the ass. From Kircher's Musurgia Universalis (1650):
In order to raise the spirits of an Italian prince burdened by the cares of his position, a musician created for him a cat piano. The musician selected cats whose natural voices were at different pitches and arranged them in cages side by side, so that when a key on the piano was depressed, a mechanism drove a sharp spike into the appropriate cat’s tail. The result was a melody of meows that became more vigorous as the cats became more desperate. Who could not help but laugh at such music? Thus was the prince raised from his melancholy.
Meeeeoooouch! My cats don't know how good they have it, little poop machines.