Union Station, Washington DC

I am looking for information about the historic plaques that hang in the West Hall of Union Station in washington DC. Theses plaques represent historical events that have occurred over the last century in the field of transportation. I believe there are 7 or 8 of theses plaques throughout Union Station in washington dc. I would like to know if there is anywhere, where I can get pictures of theses plaques possibilty on-line or maybe in a book somewhere. Any help anyone might be able to provide me would be greatly appreciated.

Thank you
Stephen Hosmer.

You might check their web site: http://www.unionstationdc.com/
The book they offer might help you.