This Columbus Monument was designed for the Chicago Exhibition. "Conveying visitors by lift to the Equator, and thence by spiral railway to the North Pole." I don't remember seeing it in Chicago, so I will assume it was never built?
Cat piano. A fine 19th century invention. "The keys press the cats' tails, each of which mews a certain note." Yes, from the way it's worded it appears as if the tails were expected to be mewing, but I'm sure they eventually figured it out.