This is a version of Lord Kelvin's Water Drop apparatus that was built for demonstrations to students visiting our lab at UVic. It simulates the process of charge separation in a thunderstorm and generates small but spectacular bolts of lightning and tiny claps of thunder.
We note a few things. The machine separates charge stored in water in a bucket (into positive and negative pools) in a manner analagous to thunderstorms via a positive feedback. The spark is very hot (look at its colour). The water in each bucket gets more and more charged leading to peculiar behaviour of the drops falling through the rings (they are repelled from like charges in the bucket and water below).
Yes, I do realize that I should have used a tripod.
