Scientific American Library: Powers of Ten : About the Relative Size of Things in the Universe by Phylis Morrison and Philip Morrison (1982, Hardcover)
Great book for an overview and understanding of the Universe right on down to the atom.
I first read this book about 1987--a library book--and I've wanted to own a copy ever since. I was SO HAPPY to have been able to find it on eBay, and for anyone interested in the Universe and/or the micro-world of the Universe--down to the atom this book is for you. Great photographs and text, both making such a complex subject understandable for a non-science guy. Highly recommend this book!