Earthquake Detector.
Description
I managed to miss today's quake, so I designed something I can print that will let me know in the future here in Cleveland.
Instructions
Print flat side down. Turn over, fasten fishing line and weight to center and hang 3/4 of the way down. When an earthquake strikes, the weight will move.


This looks almost like a weather detector stone I saw hanging somewhere while driving in the Kalahari...
If the stone is wet, it's raining. If the stone is dry, it's not. If the stone is moving, the wind is blowing really hard... etc.