I thought it would be a gold leaf electroscope https://en.wikipedia.org/wiki/Electroscope#Gold-leaf_electroscope https://en.wikipedia.org/wiki/Electroscope#Gol

I thought it would be a gold leaf electroscope https://en.wikipedia.org/wiki/Electroscope#Gold-leaf_electroscope https://en.wikipedia.org/wiki/Electroscope#Gold-leaf_electro...