On Sat, 2 Nov 2013 03:08:45 -0000, "Arfa Daily"
wrote:



"William Sommerwerck" wrote in message
...
Odd, I have one of those in the bathroom, but the *center*
position is off. Probably from the 1930's or 1940's, but I'm
just guessing.

So there are two ON positions and one OFF?

Yes, one of the on positions is dim, the other full bright.
I assume there's a diode in there.

The diode would have to be a selenium rectifier.


Why ?

Arfa
Because there weren't a lot of silicon diodes available in the 1930's?
(I'm just guessing. I wasn't the one who said it.)