CHAPTER IV
Field Trenches
The next element of the defensive position is the first line fire trenches. These are located so as to have a good field of fire to the front for several hundred yards and so constructed as to give the greatest cover and protection from the fire of the enemy.
An unbroken, continuous trench would be exposed to enfilade fire. A shell, shrapnel or grenade bursting therein would have widespread effect. To overcome these elements the trench is constructed in short lengths, with traverses between them, and technically known as the traverse type.
Better defilade is thus secured and the material effect of any burst is confined to narrow limits.
The trench interval between the traverses is known as the "bay," which should not ordinarily be longer than 18 feet. Longer bays invite heavy casualties in case the trench is enfiladed or a high explosive shell finds its mark.
The illustration, Plate 14, shows a trace of the traversed type of fire trench.