The pegs fit into a series of holes bored one inch apart in the sides of the case, thus making the shelves adjustable.

These pegs can be bought in the market in several shapes.

The shelves have slots cut in the under side at the ends to hold the projecting ends of the pegs, thus giving no obstructions to the free movement of the books.

With some forms of pegs the slots are not needed.

The uprights are made of inch and a half stuff, or even inch and an eighth.