Just wanted to mention that my wife hit another cite for “86” and a number of other period restaurant codes, in a book called “America Eats”. It’s a recently published book, taken from the raw material for an unfinished WPA project.
John, I’m not sure if I’ve ever posted it, but the earliest we’ve currently found for the term “eight-six” (86) is a Walter Winchell column from 1933, found by Barry Popik. It was soda jerker slang for “out of that item.”
It came up in a thread some years ago. But America Eats is the result of more or less academic field research, rather than mere newspaper reportage, so it’s got a bit more weight. It also apparently has more code numbers cited than the Winchell. (This was in the big NYC library, and I only had a few seconds to look at it before we left, so I can’t provide much more.)
IIRC, as a kid I was told it was a thing you do inside, like taking off your hat, and that you re-button it when you leave a building.
Some other adults in the conversation said it was more akin to a relaxed posture, like loosening your tie after work - you unbutton the bottom button because it’s more comfortable.
Along the “nuts and bolts” reason, I also recall that if your vest is snug (but not “tight” as in you can’t sit down) before a meal, it will be very tight after a meal. So, sometime during the meal, you unbutton the bottom button to make some room.
Finally, I think it might be something you’d do if you’d put on a few pounds since the last time you wore the vest, and you can’t button the lowest button
http://www.worldwidewords.org/qa/qa-eig1.htm Quinion who is usually as responsible as we can find, states
Michael is indeed one of the best out there. Barry Popik’s find of 1933 is the earliest. The mid-20s possible example is from a source that can only be said to be dated between 1926-1935, and the meaning isn’t exactly clear.