Mechanical Fire-Control Computers: Gears, Differentials and Cams
Excelsior10000 · Documentary · YouTube title: Mechanical Computer (All Parts) - Basic Mechanisms In Fire Control Computers
Why it's here
HN commenters repeatedly recommend it as a beautiful, approachable explanation of analog mechanical computation, and many have rewatched it.
What it covers
A 1953 US Navy training film explaining the basic mechanisms in mechanical fire control computers aboard ships. It shows how gears, differentials and cams solved mathematical problems in permanent mechanical form.