Friedrich Engels

Berm

Written about January 28, 1858.

From the English.

["The New American Cyclopædia", Vol. III]

Berm, in fortification, a horizontal ledge of earth left between the upper inner edge of the ditch and the exterior slope of the parapet of a field-work. It is generally made about three feet wide. Its main object is to strengthen the parapet and prevent the earth of which it is composed from slipping into the ditch during heavy rains, thaws, &c. It sometimes serves as an outer communication round the work. It must not be overlooked, however, that the berm is a very convenient resting and rallying place for storming and escalading detachments; in consequence of which it is entirely omitted in permanent fortifications, and in others is protected by a loopholed wall, thus forming a covered line of fire for infantry. In field fortification, or in the construction of siege batteries with a ditch in front, a berm is generally indispensable, as the scarp of the ditch is hardly ever revetted, and without such a ledge both scarp and parapet would soon be destroyed by the vicissitudes of weather.