It wasn't that long ago in terms of history when books were very rare either. One of the kings of France (I think Louis 14th) had what was considered to be a large library at the time. In all he had 24 books. Not 240, not 2,400, just 24 books. Not enough to fill even one bookcase now days, but back then books had to be hand copied (before Gutenberg) and so books were both rare and expensive. In fact those who had them had them held in leather covered wooden binders which were chained to the table. The idea was that if a rich person had a visitor who could read they would be able to read the books (with their host's permission of course) but the books couldn't just up and walk out the door in the trunks of the guest when they returned home. Now days we use bar codes to do much the same thing but it's done in order to make sure that someone pays for the book before they leave the store.
