How to cram many books into a book shelf

When I had to forgo one cupboard, I was left with no choice but to throw away about 250 books. Even that I still the spaces in the bookshelves insuffient for my books. Later I thought of an idea of economise space. What I did was to place those books which I will not be referencing at the book. I could place four books back to back in this way and had enough to place a row of books on the front.

If you ever have too many books to be put into limited spaces in the bookshelves, use the above method.

So much for cramming books into limited spaces in the bookshelves.