The gentleman to the right is Mr. Harry Katz. He has written several great pictorial books, two of which I own--Baseball Americana & Civil War Sketch Book.
He was a curator for the Library of Congress for years, and has done some two dozen exhibits for them.
He is a very nice man. Plus he likes baseball & the Civil War.
The Sketch Book is features in the May, 2012 National Geographic, so go read about it. Please.
Then remember all the work done here and at emergingcivilwar.com on the Special Artists who drew the sketches from which Frank Leslie's and Harper's created their illustrations.
Embedded journalists are common now, but not then--it was a dangerous and exciting job--groundbreaking, in fact.
Reread the posts in ECW, and First Fallen, of course, and get ready to read my interview with Mr. Katz as soon as it comes up.
I'll let you know.