Thank you, Andy for the background information. That explains everything in the video. It looked more impressive than the damage (none) that it caused!
We don't have many electric trains up my way to see this occur. I have to travel to Boston to see any electric action and that's over 55 miles from me.
High voltage is still very scary stuff. Way back when I was an electronics technician, I used to work with CRTs. These devices had high voltage transformers in them that would arc over and burn if the unit got very dirty inside. We used to get systems back from the diamond mines in South Africa and from some of the oil drilling equipment from Saudi Arabia. The dust inside these units was horrendous. Eventually the fly back transformer, which is used to drive the high voltage for the CRT its self, would arc over and burn. The ensuing fire would usually melt everything inside the case and the units were destroyed.
John