Trenches

The communications, boyaux, or zigzags, as well as the parallels or places of arms opened by besiegers against a fortification are trenches. They are from 6 to 10 feet wide and about 3 feet deep. (See Parallels , and Siege .) To mount the trenches , is to mount guard in the trenches, which is generally done in the night. To relieve the trenches , is to relieve the guard of the trenches. To scour the trenches , is to make a vigorous sally upon the guard of the trenches, force them to give way, and quit their ground, drive away the workmen, break down the parapet, till up the trenches, and spike their cannon.