The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 5: Forts and Artillery.
Francis Trevelyan Miller, Ed.

[202] Landing, the works thrown up by the Federals were increasingly strong, and the private soldier gradually learned his own individual responsibility in preparing the earth-and-log protection.

In the Seven Days Battles, while they were on the defensive, the Union troops took advantage of all sorts of protection — woods, rail fences, trees, irregularities of the ground, and houses, but made little use of earthworks. There were so many of the other forms of protection and time was so precious that earthworks did not figure much in their calculations.

The last scene of the Peninsula campaign was placed at Malvern Hill, and Harrison's Landing, which was strongly fortified. There was thrown up an improvised fortress where, after several days of victorious pursuit of the Federals, the Confederates were checked.

The system of fortifications in this first campaign paralyzed the offensive movements on both sides, saving first the Confederates and then the Federals probably from total defeat, and proving beyond doubt that entrenchments of even the slightest character gave excellent results in defensive operations, but also that they must be constructed “with a celerity that defied the rapid march of the opposing army and with an ability and aptitude that enabled a defender to transform an entire field of battle into an improvised fortress.”

Yet, despite the experiences of this campaign, the lesson was not fixed in the minds of the combatants. The former schools of military teaching still showed their effects. In the campaign between Lee and Pope, in 1862, but little use was made of field-works, and at Antietam Lee fortified only a part of his line, though strictly on the defensive. But Antietam evidently taught the lesson anew, for we find that same Confederate army at Fredericksburg with lines that defied the efforts of the assailants as effectually as permanent fortifications could have done.

The manner of construction of these works of hasty entrenchment usually was this: The men, deployed in a line of