British Pathe put an enormous archive of historic clips into internet - www.britishpathe.com. First thing that I've searched there was "testing" and got 57 pages of clips (2834 results). I've watched first 10 pages and here are some interesting clips about some kind of stress testing.
They don't have normal embedding system, so all links will be opened in British Pathe website.
See also other parts:
Testing In History: Part II - Functionality Testing
Testing In History, Part III