The Prohibition Joke

One of the dialogue slides near the beginning of the film contains a "prohibition" joke. I was under the (perhaps mistaken) impression that the earliest mention of prohibition was in 1917.

I am watching a sound version of the film with an voice-over announcer giving background info on the actors, director, etc, and unfortunately a lot of spoilers in advance of some good gags.

Were updated dialogue slides added to this film when this voice over track was added many years later? Or would a prohibition joke have been something that would have gotten a laugh in 1914?

- Frank
"We are one big happy fleet!" - KN Singh