Book excerpt: Great Photographs of the Civil War brings together in one volume the most evocative Civil War photographs ever published. The images--selected by Time Life editors from thousands of photographs preserved in museums and collections around the country--tell the epic story of a nation divided. Reflected here are the tireless efforts of pioneering photographers who used heavy equipment and portable darkrooms mounted on wagon beds to record this fateful struggle. The editors have assembled 300 gripping images, some of them recognized classics and others rarely seen, into 20 chronological photo essays. Here, the crucial events of the war, from the bloodiest day at Antietam and the Confederate high tide at Gettysburg to the battles for Atlanta and the climactic siege of Petersburg, are conveyed with power and precision in the defining photographs of the conflict that redefined our nation.