Here is one from the past. Can you tell me what it is?
"This patent was withdrawn and reissued 20 Jan 1820, "by act of Congress." It is one of the most important woodworking-relating patents, and was a key innovation in the industrial revolution."
Just looking at it makes me think it's got something to do with an early lathe duplicator, like the part F rides along the profile of rotating part T while part E cuts into part U....
What really worries me is that it looks like part T and U rotate as well....