How did timothy o'sullivan's a harvest of death, gettysburg, pennsylvania, july 1863 respond as a new medium and how did it impact the nation?

This photograph of the rotting dead awaiting burial after the Battle of Gettysburg is perhaps the best-known Civil War landscape. It was published in Gardner’s Photographic Sketch Book of the War (1866), the nation’s first anthology of photographs. The Sketch Book features ten photographic plates of Gettysburg—eight by Timothy H. O’Sullivan, who served as a field operator for Alexander Gardner, and two by Gardner himself. The extended caption that accompanies this photograph is among Gardner’s most poetic: "It was, indeed, a ‘harvest of death.’ . . . Such a picture conveys a useful moral: It shows the blank horror and reality of war, in opposition to its pageantry. Here are the dreadful details! Let them aid in preventing such another calamity falling upon the nation."