The population density is also much less if we scaled the population of my apartment up to 13,000 km², but that isn't how metropolitan areas are traditionally measured. The NYC metro area includes three states, lots of sprawl - so it is much less dense.
I remember the local village library books only had dates on the borrowing slips.
My library card was a 5x5cm card sleeve. If I borrowed something, the return date was stamped in the book, and on the book's removable 5x15cm slip. That slip was put inside my card, and probably ordered by due date in the librarian's index file.
