Field fortifications during the American Civil War consisted of temporary works constructed of earth and wood that were designed to increase the defensive capabilities of a body of troops holding a position. The two basic components of most field works consisted of the parapet and the ditch. The parapet was an earthen embankment raised high enough to provide cover from enemy fire, while the ditch supplied soil to construct the parapet and served as an obstacle to impede an assault on the field work.
Most field works were designed according to a standard set of proportions that regulated the height and width of their various elements. They could also be given any outline necessary to adequately fortify a position. This mostly consisted of straight lengths of parapet arranged to provide for a mutual defense of the various faces and flanks of the work. The length of parapet in an outline depended on several factors, such as the number of troops and pieces of artillery necessary to hold the position; the circumstances of the site of the work and its relationship to the ground around it; and whether it was an isolated post or an element within a line of works.
Competent Civil War military engineers such as John G. Barnard and Charles Dimmock had an extensive repertoire of standardized figures such as lunettes, redans, square and polygonal redoubts, bastioncd lines of defense, and cremaillere lines that they used to design field works. Certain outlines incorporated particular strengths and weaknesses; for example, a square redoubt would have four salient angles, producing large sectors without fire at the corners of the square. However, such a work was closed at the gorge and made a good shelter for troops holding an isolated position that could be attacked from more than one direction. Military engineers were by no means limited by the standardized figures outlined in various manuals and textbooks at their disposal. Indeed, during the Civil War they produced an extremely wide variety of outlines, each one designed to meet the particular needs and conditions present at a specific site. Furthermore, almost all of the various types of field works could be combined to form lines of defenses to cover the front of an army, or to protect a strategic point.
Semi-permanent field fortifications
Within permanent fortifications, a redoubt, or reduit, was placed inside a larger outwork, and was designed to prolong the defense of the work after its scarp had been breached. It also provided an interior shelter for the collection of troops and materials necessary for the defense of the outwork. In the context of field fortifications, redoubts could be laid out as any regular or irregular convex polygon, as necessary to adequately fortify a particular site. The most common forms were four- and five-sided figures. This type of field work could be adapted to fortify
This large star fort called Fort Phelps formed part of the Federal defenses built by 1865 to protect Chattanooga in Tennessee. Note the cross-shaped blockhouse in its upper terre-plein. (Official Military Atlas of the Civil War)
Was this article helpful?