Another girls' weekend is on the books and summer is in the can. And it's a good thing we finally threw in the towel because I'm knocked out.
On the books can either refer to law books or financial books. I'm guessing that the phrase I used originated with the latter - in that it refers to the official end of something ongoing.
In the can comes from the film industry: the "can" is a film canister - where movie film goes when you're done recording. The film industry also gives us that's a wrap - wrap may be an acronym for wind, reel, and print (but it probably isn't). I wonder if it refers to the act of winding the film to stick it in a can.
You'd think, from the above, that wind up is from the film industry too, but the film industry wasn't a thing back in 1825 when the expression first appeared. And according to the Online Etymology Dictionary, wind meaning to wrap is etymologically unrelated to wind, as in the thing that answers blow in.
Threw in the towel and knocked out both come boxing.
And that is all she wrote - referring, obviously, to me, and the fact I'm finished writing now. Or possibly to the song That's All She Wrote by Ernest Tubb, which is about a "dear john" letter. (A phrase that may have come from World War II, referring to a woman writing a breakup letter to her GI, telling him she was leaving him for some draft-dodging peacenik. Dude, that's cold.)
Are all languages full of such cryptic idioms?