https://www.youtube.com/watch?v=rL0_vOw6eCcThis video from 1949 produced by the Hamilton Watch company (A heritage American watchmaker), uses a Hamilton 747 movement to instruct the audience on how an automatic wristwatch (or pocketwatch) works. Save for some improvements and complications by various manufacturers, the general engineering concept for a basic timepiece has been largely unchanged for 300 or so years. I am not very mechanically minded, but certainly the Mechanics, Engineers and Architects amongst you should be informed/entertained by this video.