what was the earliest dip switch?

[JonE]

Having searched the threads, I see a few people with later 20's cars have likely abandoned the High Low switchpanel headlight function and just wired dip-switch to the high.

I'd like to know when the first dipswitch came in and what did it look like? i.e. was it the same as the Nippy, sort of cut off conical and strapped to steering column? Or was there ever a dash mount?