bookshelf to enchantment tables don't start right away

What happens:

I place a bookshelf near an enchantment table and particle effects do not start right away. they start in about 15 seconds.

How to recreate this:

 All partial effects required.

Put down a enchanting table. then put down a books shelf like you would for an enchanting table, with 1 air block in the middle.you will see no particles for a short amount of time.