The Disappearing Frontier: A Chronicle of the Old West by Emerson Hough is a fascinating non-fiction essay on how the American West experienced change in the 19th century. The author tells in detail about the important historical events of that time, which influenced the disappearance of the border between civilization and wild territories. The book reflects the changing mentality of Americans, their desire for new territories, as well as the dangers and challenges they faced during their descent into the West. The Disappearing Frontier: A Chronicle of the Old West is a must-read for anyone interested in American history and the spirit of adventure.