Add in the fact that paper manufacturers round the numbers down, that “perfect” half size goes out the window immediately on the first division. And gets worse as the paper size gets smaller.
I believe that’s basically the basis of the American size scheme. It’s just the size of the paper the paper maker would give you. Records seem to indicate it was based on the sizes of paper used for bookmaking, where a standard sheet would be folded once, twice, or three times to make book page inserts.
Add in the fact that paper manufacturers round the numbers down, that “perfect” half size goes out the window immediately on the first division. And gets worse as the paper size gets smaller.
I believe that’s basically the basis of the American size scheme. It’s just the size of the paper the paper maker would give you. Records seem to indicate it was based on the sizes of paper used for bookmaking, where a standard sheet would be folded once, twice, or three times to make book page inserts.