35
A-frame
Country of origin: United Kingdom (in Belgium)
Date of construction: c. 1917
Location: Archaeological site, near Ieper, Belgium
THE MILITARY MANUALS supplied to the warring nations at the outbreak of war were full of advice in the construction of trenches. Differing only in detail, these texts expected and predicted that the digging of trenches would be a temporary defensive measure only. In fact, trenches had long formed an important part of the history and science of warfare. In siege operations in particular, trenches were significant. Dug as close to the footings of castle walls as possible, they provided protection for the men who were digging shallow tunnels or saps that were to undermine and breach the defenses. They would also serve to house the assaulting infantry intent on that moment when they could surge into the fray. This principle, developed in medieval times, would be reenacted in unrest in the longest and largest siege operations in history, fought on the Western Front from 1914 to 1918.
The development of this type of trench warfare was an inevitable consequence of the improvement in weaponry, and in particular rifled weaponry, which could fire—with great accuracy, range, and velocity—projectiles from as small as the rifle bullet to as large as the artillery shell. Unprotected, the infantryman was vulnerable to devastating firepower at longer ranges, and with the advent of quick-firing weapons such as the latest field guns and machine guns, the only way to “bite and hold” a position was to ensure that men got to ground as soon as possible, digging into the earth to gain the maximum protection that could be afforded. Rifled weapons had contributed to the development of trench warfare in the Civil War in 1861–65, which had gone from Napoleonic ranks to trench operations over its five years; and its appearance in modern warfare was heralded in the Russo-Japanese War of 1904–5.
In the First World War, entrenchment of the Western Front was an inevitable consequence of the fight for position that took place during the “race for the sea” in the autumn and winter of 1914. From this point onward the engineers of all the protagonists worked to develop and improve trench fortifications within unfavorable ground conditions, and to protect the infantry from both the attentions of the enemy and from the elements. The best positions were quickly taken and the lines set in position that would become the zone of trench warfare for some four long years.
Engineer trench design needed consideration of ground conditions. The trench illustrated was one that was excavated in the Ypres Salient in 2005 and demonstrates in some detail how these specialist soldiers coped with the difficult ground—and shows how unexpected challenges of extended siege warfare became a high science in itself. Recent archaeological studies in northern France and in Flanders have allowed scientists and historians to add further dimensions to our understanding of trench warfare provided by accounts, official histories, and photographs. Here, engineers have tried to combat the inevitability of water collecting in the bottom of the trench, thereby promoting “trench feet”—a condition akin to frostbite—as men struggled through the water-logged trench. Prefabricated wooden A-frames were sunk into the ground. The crossbar of the “A” provides a support for an elevated walkway or duckboard. Water could accumulate below and could be drained away, if skillfully done. The rising timbers of the frame provided rigid support for the trench sides, known as slopes, which were important if the sides were not to collapse in on the trench garrison. This revetment differed from trench to trench, from army to army. In the case illustrated from the Ypres Salient, corrugated steel was used; however, sandbags, wattle hurdles, timber—all were tried according to whatever was available. Trench construction varied between nations—wattle was often used as a natural revetment type.
In many cases, the depth of trenches was limited by the local geological conditions, with water-bearing layers often close to the surface. In such situations, sandbags were used to build up the trench to an acceptable height of parapet. Building up the parapet meant using the A-frame in such a way as to support construction of “high command” trenches, or simple sandbag breastworks.
In all cases, the trench lines showed increasing sophistication as the war moved from temporary trenches to those intended to house a garrison committed to a lengthy stay. With the British and French adherence to the doctrine of the offensive—with trenches little more than a “phase”—the development of the A-frame represented a recognition that trench warfare was here to stay.