RAMPART, probably from Ripa, an embankment, from which is derived the Italian word "Riparo,' and theFrench word "Rempart," is, in modern fortification, a mass of earth often nearly 80 feet thick, surrounding a town or a ;military position, or constituting the faces of an outwork, and supporting the parapet ; and its use is to protect the interior of the place or work against any sudden enterprise of the enemy, as well as by raising the parapet to give the defenders a superiority of elevation with respect to the works of the besiegers.
The ramparts of ancient fortresses were walls of stone or brick, frequently from 60 to 100 feet high and 20 feet broad, including the galleries made in them : round or angular towers were formed at intervals along the walls; and, by means of the galleries, the defenders could pass within the thickness of the wall from tower to tower. The rampart was surmounted by a parapet seven feet high and two feet thick, which was provided with battlements; the rampart was loop holed, and, in order that the exterior foot of the high wall might be defended, machicolations were formed at the top, particularly over the entrances. [BASTION.) A great mass of earth was raised against the interior aide of the walls, nearly as high as the top, in places where elevated ground or the enemy's works on the exterior allowed access to the top of the wall to be gained in force : and on this mass the cohorts were drawn np in order of battle. (Vitruvius, lib. i., cap. v.) The modern rampart is surmounted by a parapet of earth, on the interior aide of which, towards the town, is a nearly level space, varying in breadth from 35 to 40 feet, called the terreplein of the rampart; on this terreplein the artillery is placed : and in the rear of the guns there is room for the movements of the defenders and the conveyance of the ammunition. The exterior and interior sides of the rampart are formed with slopes making angles of about 45 degrees with the horizon : or they are retained by revetments, or walls of brick or stone, nearly upright, the exterior face of the rampart constituting the escarp of the ditch in front. The rampart immediately surrounding a place is divided, in the direction of its length, into parts making salient or re-entering angles with one another ; and these parts constitute the faces and flanks of the bastions, and the curtains which connect the latter together. Not more than 30 feet are allowed for the breadth of
the terrepleins of the ramparts of outworks, measured from the foot of the parapets, in order that the enemy may not be able to form batteries for artillery upon these terrepleins. The terrepleins of all ramparts should have a small slope down, towards the interior, in order that the rain-water may not lodge on them, and that the defenders near the interior edge of the rampart may be effectually covered by the parapet. The terreplein and the interior slope of a rampart, as well as the surface of the parapet, are generally covered with turf. A rampart whose exterior side is of earth, or without a revetment of brick or atone, might be easily ascended by an enemy at the time of an assault ; and the palisades or fraizes which, in that case, would be planted in it for the purpose of impeding the progress of the enemy, might be easily destroyed by artillery, so that the place would be liable to be carried by a sudden assault. It is usual therefore always to have a revetment either supporting the earth or detached (see ItevrrxExy), except in cases where a is rendered impossible by wet ditches.
The relief, or height, of a rampart is regulated by the occasional necessity of employing a fire of artillery from the rampart, and, at the same time, a fire of musketry made over the glacis by men stationed in the covered way beyond the ditch in front of the rampart : for this purpose a line of fire from the rampart should pass three or four feet above the crest of the glacis in its front, in order that the wind of the shot may not injure the defenders. The relief of a rampart with its parapet may, therefore, be thus determined :—On a drawing repre senting a vertical section of the works let a line be drawn from the foot of the glacis, through a point taken at 3 or 4 feet above the crest of that work, and let it be produced till it cuts the interior slope of the parapet on the rampart : this intersection will give a point in the axis of a gun placed on the rampart, or a point a few inches above the sole of the embrasure, that is, about 34 feet above the terreplein of the rampart; and, because the artillery and the gunners are to be protected by the parapet, if 74 or 8 feet be added to the height of the terreplein of the rampart, above the ground, the sum will be the required height of the crest of the parapet.