Porcelain Keyless Lampholder

[tom baker]

My wife and I were at several McMenamins over the weekend, they all feature many different types of luminaires, and very commonly use a porcelain lampholder with small 7 1/2 watt lamps in various colors.
My wife asked and my question is what is a porcelain keyless lampholder? What makes it a "keyless"?
(Note: Mcmenamins is 50+ historic properties, brewpubs in the SW Washington and Oregon area. We went to all the locations, got passport stamps and and are now "cosmic tripsters")

 

[drcampbell]

It's "keyless" when it doesn't have a pull-string switch built into the porcelain lampholder.


The opposite kind of porcelain lampholder, which I've never heard called "keyed".
View attachment 19972

 

[LarryFine]

Keyed:

 

[JFletcher]

Keyed:

View attachment 19973

Was an actual key of sorts used at some point, or just a switch handle that looks like a key?

 

[zbang]

Was an actual key of sorts used at some point, or just a switch handle that looks like a key?

The latter, I find a post by one Jreaf-

The old gas lamps had "keys" that you used to control the amount of gas and thus the light level, essentially an early dimmer.

Vaguely apropos of that, lots of older telco equipment switches are referred to as "keys". (And to muddy the waters, the classic office telephone with line select/hold buttons is called a "key set" as part of a "key system". I still have my BSPs on those .)