Your Great grandfather holds a very important place in our country's history.
I’m a researcher, so once I learn something about an ancestor, I dig down to China. My library on both the Civil War and Revolutionary War is mammoth. Gettysburg is one of my very favorite topics, and Chamberlain is my hero. I’ve visited his grave and home. Because I went to U of Chicago, my preference is for original sources over books about, so Chamberlain’s books are cherished. Actually, so is Longstreet’s.
http://www.iment.com/maida/tv/misc/gettysburg.htm