The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 2: Two Years of Grim War.
Francis Trevelyan Miller, Ed.

Entirely independent of the action in which the Left Grand Division under Franklin was engaged against the right wing of the Confederate line, Sumner's Right Grand Division was engaged in a terrific assault upon the works on Marye's Heights, the stronghold of the Confederate forces. Their position was almost impregnable, consisting of earthworks, wood, and stone barricades running along the sunken road near the foot of Marye's Hill. The Federals were not aware of the sunken road, nor of the force of twenty-five hundred under General Cobb concealed behind the stone wall, this wall not being new work as a part of the entrenchments, but of earlier construction. When the advance up the road was made they were harassed by shot and shell and rifle-balls at every step, but the men came dashing into line undismayed by the terrific fire which poured down upon them.

The Irish Brigade, the second of Hancock's division, under General Meagher, made a wonderful charge. When they returned from the assault but two hundred and fifty out of twelve hundred men reported under arms from the field, and all these were needed to care for their wounded comrades. The One Hundred and Sixteenth Pennsylvania regiment was new on the field of battle, but did fearless and heroic service. The approach was completely commanded by the Confederate guns. Repeatedly the advance was repulsed by well-directed fire from the batteries.

Once again Sumner's gallant men charged across a railroad cut, running down one side and up the other, and still again attempted to escape in the same manner, but each time they were forced to retire precipitately by a murderous fire from the Confederate batteries. Not only was the Confederate fire disastrous upon the approach and the successive repulses by the foe, but it also inflicted great damage upon the masses of the Federal army in front of Marye's Hill.