Civil War Field Fortifications
Trench Cavalier
There were two basic methods that could be used to construct
a trench cavalier. When the enemy's fire was light or the soil was easy to
work the trench cavalier could be raised by stacking successive rows of gabions
on top of each other while throwing an ever increasing amount of soil over
the gabions to form successive elevations of parapet. The soil for the massive
parapet was produced by widening (but not deepening) the trench to the rear
of the parapet. As the height of the
stacked
rows of gabions increased, steps were also constructed on the interior side
of the parapet so that troops could easily mount the parapet. Once the parapet
had reached the required height sand bag loop holes were made along the top
of the parapet that would allow the troops lining the parapet to fire down
into the covered way without overly exposing themselves to return fire.
The second method of constructing a trench cavalier required
a tremendous amount of material and more time and labor than most besieging
armies were willing to commit to the capture of the covered way, but it also
produced a very solid structure that could not be easily broken down by the
garrison's defensive fire or quickly removed if captured in a sortie. Viewed
in transverse section this second type of cavalier had something of the
appearance of pyramid and was used when the enemy's fire was rather heavy
or the soil was difficult to work. The base of the cavalier was constructed
by placing a row of gabions against the side of the trench nearest the covered
way. Three or four rows of gabions were placed on the next level (the natural
level of the ground) and filled with soil. Soil was then thrown over the
gabions to form a parapet. More rows of gabions were placed on top of the
lower level, making sure that they were positioned across the
seams
between
the gabions of the lower level. This procedure was repeated until just one
row of gabions was needed to form the highest level. Steps were constructed
along the interior side of the cavalier to allow easy access to the top of
the parapet where sand bag loop holes were made to protect the troops as
they fired down into the covered way.
Trench cavaliers were rarely used in the American Civil War. Ewing's Approach against the Stockade Redan at Vicksburg probably provides the best example of the use of a trench cavalier in the Civil War. When the Federals' main sap reached a point a few yards from the salient of the redan's ditch saps were run to the right and left parallel to the ditch. The nature of the ground, which fell very sharply downhill just behind the trench, and the relief of the redan precluded any attempt to raise the parapet of the cavaliers high enough for the Federal troops to fire down into the ditch. This was really quite important since the Confederates were able to continue to use the ditch as the starting point for their mining operations against the Federal approach. Federal miners were forced to a dig deep mine that ran at eccentric angles to the salient of the redan which delayed their mining operations against the redan. Compared to the unsuccessful Confederate counter mining operations that had to start from the interior of the Third Louisiana Redan, their mines in front of the Stockade redan were really quite successful, primarily because they were able to sink their galleries from a forward position in the ditch. Had the Federals been able to raise their cavaliers high enough to clear the redan's ditch Confederate mining operations would have been as severely hampered as they were at the Third Louisiana Redan.
Saps Parallels Lines of Circumvallation and Countervallation Mortar Batteries
Contents Home
Page Major Works
Minor Works
Glossary
Copyright (c) PEMcDuffie 1998