On Feb 15, 2006, at 10:43 AM, Bill Kuncicky wrote:

> The socket has three terminals at the bottom.  Two of them are
> connected through the switch.  Turn the switch on and these two
> are connected.  Turn the switch off and these two are not
> connected.  The third terminal goes to the side of the socket
> -- the part that has the threads on it for the light bulb to
> screw into.  The third terminal doesn't look like it is meant to
> have a wire connected to it, although there is a screw there.

Sounds like a socket for a three-way lightbulb.

Normally a lightbulb has one connection via the threads
and one through a "button" on the bottom.  Three-way bulbs
have two contacts on the bottom for two filaments.

BillW
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