That's an excellent piece that C-H has clipped and posted. There are a lot of standards around today which exist for various historical reasons.
50Hz power was also used in America in the past. Bjarney sent me a short article on the changeover from 50 to 60Hz power in Los Angeles in 1936.
Scott,
I didn't keep a copy on disk -- Maybe you could forward a copy of that article to anyone interested?
