Silent Piano

Apparently in the later years of the 19th Century, someone had a brilliant idea to manufacture a piano that you couldn't actually play notes on.  It was used to strengthen the fingers, without driving the neighbours mad with endless scales.

They were manufactured in USA, and this model (which somehow ended up in our front room - don't ask; it's a long a boring story); came to Australia in a roundabout way, having first of all been exported to the UK, and thence to this country.