Gettysburg, then and now

A photo (left) of the 93rd New York Infantry's drum corps taken between August 1863 and November 1863.  Union re-enactors(right) marching by Confederates at Bushey Farm in Gettysburg. (Library of Congress/ AP)

A sketch (left) of the Union Army galloping into action on horseback at the Battle of Gettysburg, Pa, which took place July 1-3, 1863. Mounted Union re-enactors (right) taking part in a demonstration of a battle at Bushey Farm in Gettysburg, Pa. (U.S. Army Signal Corps / AP)

A photo (left) of Lincoln's “Gettysburg Address,” on Nov. 19, 1863, in Gettysburg, Pa. Re-enactors (right) demonstrating a cavalry battle near spectators during ongoing activities commemorating the 150th anniversary of the Battle of Gettysburg. (Library of Congress/ AP)

A photo (left) of the rear view of the camp of Capt. John J. Hoff of the Union Army in Gettysburg, Pa., in July 1865. Members of the 1st Tennessee waiting to take part in a demonstration of a battle. (Library of Congress/AP)

A sketch (left) of the field hospital headquarters at the Battle of Gettysburg in July 1863. Members of the Union Murray's Brigade (right) setting up camp during ongoing activities commemorating the 150th anniversary of the Battle of Gettysburg. (Library of Congress/ AP)

A sketch of soldiers in camp at night between 1860 and 1865 (left). Re-enactors (right) portraying Union soldiers in the Murray's Brigade cooking their rations. (Library of Congress/ AP)

A photo (left) taken between Sept. 8, 1862, and June 6, 1963, of soldiers of the 6th Regiment Massachusetts Volunteer Militia outfitted with enfield muskets in front of their camp.  Re-enactors (right) portraying Union soldiers in Murray's Brigade. (Library of Congress/AP)

A photo (left) of John L. Burns, the "old hero of Gettysburg," with his gun and crutches in Gettysburg, Pa, in July 1983. A Floridian (right) portraying a wounded soldier from the 1st N.C. Infantry. (Library of Congress/ Ap)