[sandworm101]

The Foucault Pendulum is on my list of three dead-simple machines that prove science is real.

(1) Using a soup can and some string to measure radiation: https://en.wikipedia.org/wiki/Kearny_fallout_meter

(2) Measuring the force of gravity, and thereby weighing the earth, using a tuna can and some other string. http://www.fourmilab.ch/gravitation/foobar/

(3) Using a string and a bowling ball prove the earth is round without going outside. https://en.wikipedia.org/wiki/Foucault_pendulum

[erikig]

I didn't know about Cresson_Kearny [1] until this but he was pretty great. He reminds me of a cold war Macgyver-like survivalist with a number of interesting gadgets [2]

[1] https://en.wikipedia.org/wiki/Cresson_Kearny

[2] https://en.wikipedia.org/wiki/Kearny_air_pump