That was quick - and getting very close. Yes, I remembered the discussion of artesian wells in the lecture, and the reference to ancient uses. He was applying it to the generation of power (probably to turn turbines or create steam) but it wasn't hydropower. I don't see a link to the lecture - he explained it clearly, and that's what I'm going for.

MOM says you earned yourself a beer out on the screened in porch. :)