Library Questions to Ponder

     While some of my colleagues and I were working deep in the stacks today, the following questions came up, which I present for your consideration. Comments & answers welcome. 

1. Do books contain knowledge even if no one is reading them?
2. What is the sound of a book being read?

     My answer to #1 is yes, even if the knowledge is unrealized. I am still puzzling over the answer to #2.