On Tue, 29 Apr 2014 12:09:40 +0100, "Max Demian"
wrote:

Mercury Arc Rectifier [100 yrs old]
http://www.youtube.com/watch?v=QY6V2syGnZA

Prior to the renovation of the Royal Opera House just before the Millennium,
they used mercury arc rectifiers to power the First World War submarine
motors they used for the stage machinery.

I would have loved to see that in operation. Hope it found a good
home?