I don't come across history books very often that mention my ancestors, but the Emery family has been named in a few. Aside from the book "Conrad Emery and His Descendants" written by Frederic B. Emery, it's interesting to see your family documented in a book.
The entry below appeared in "The history of Fulton County, Illinois" written by Charles C Chapman & Co in 1879.
Edith (Fisher) and David Emery were my great great great great great grandparents (though they misspelled David's last name). Their son, my great great great great grandfather Henry would eventually migrate north to Henry County. (Knox county separates Fulton and Henry counties).