Jinx wrote:
> wikipedia itself disagrees with that
>
> http://en.wikipedia.org/wiki/Earth_battery
>
> The process is simply dissimilar metals in an electrolyte, same as
> a nail and a penny in a lemon

Yes, I read that article too -- but they are two different phenomena. The 
early telegraph systems that relied on the "earth current" had to use 
correct polarity (so the "chemical" battery would not fight the earth 
current).

Vitaliy 

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist