Comment by AnotherGoodName

I mean they are still sold at your local hardware store. The bulb in the tilt switch below is the same as the mercury tilt switches that have been around for 100 years.

https://www.homedepot.com/p/Hiland-Anti-Tilt-Switch-Mechanic...

OMG that's a switch and switches are used in nuclear weapons! (lol!)

Of course this is even a step further removed. He had mercury and some tilt switches use mercury and switches are used in nuclear weapons therefore he was making a bomb!