Upvote:1
If you mean electromagnetic generator, it was first designed by Faraday (see Wikipedia, "Electric generator") and it is called the Faraday disk.
But strictly speaking, you can "mechanically generate electricity" in another way: by rubbing a piece of glass or another substance. This is known since antiquity. A machine with wheels, called friction generator was invented by Otto von Guericke in 1663. See Wikipedia "Electrostatic generator".