Let's see if this thread can get some traction. I'm always amazed, when I see some old tools, that anybody actually thought that up, and made it. Some things I have no idea what they are for, or how they might be used. I've seen many old specialty tools that get my standard best guess: paper weight. You all probably have some interesting things in your collections that would be interesting to share. And I'll start with this:
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Found this in the new house we bought. The house was built in 1892 and we are the second owners. I had to search the patent number to figure out what it was.
(btw - I posted here because I'm guessing most of the interesting tools will be hand tools.)