_Line of_ COUNTER APPROACH, a trench which the besieged make from their covered way to the right and left of the attacks, in order to scour or enfilade the enemy’s works. COUNTER-_Battery_, a battery used to play on another in order to dismount the guns. See BATTERY. COUNTER-_breastwork_. See FAUSSE-BRAYE. COUNTER-_forts_, in fortification, are certain pillars and parts of the wall, distant from 15 to 20 feet one from another, which are advanced as much as may be in the ground, and are joined to the height of the cordon by vaults, to sustain the chemin de rondes, and the part of the rampart, as well as to fortify the wall, and strengthen the ground. See BUTTRESSES. COUNTER-_guards_, in fortification, are small ramparts, with parapets and ditches, to cover some part of the body of the place. They are of several shapes, and differently situated. They are generally made before the bastions, in order to cover the opposite flanks from being seen from the covert way; consisting then of 2 faces, making a salient angle, and parallel to the faces of the bastion. They are sometimes made before the ravelins. See FORTIFICATION. COUNTER-_round_. See ROUNDS. COUNTER-_mines_. See MINES. COUNTER-_trenches_. See SIEGE. COUNTER-_working_, is the raising of works to oppose these of the enemy. COUNTER-_swallow’s-tail_, in fortification, is a kind of an out-work very much resembling a single tenaille. _To_ COUNTERMAND, is to give contrary orders to those already given; to contradict former orders, &c. COUNTERMURE, a wall built up behind another in order to increase the strength of any work. COUNTERMARCH, a change by wings, companies, subdivisions, sections, or files, whereby those who were on the right take up the ground originally occupied by the left; generally used in changing the front. See MARCH. COUNTERSCARP, in fortification, is properly the exterior _talus_, or slope or the ditch, on the farther side from the place, and facing it. Sometimes the covert way and glacis are meant by this expression. See FORTIFICATION. COUNTERSIGN, in a general acceptation of the term means any particular word, such as the name of a place or person, which, like the parole, is exchanged between guards, entrusted to persons who visit military posts, go the rounds, or have any business to transact with soldiers in camp or garrison. It ought always to be given in the language most known to the troops. COUNTERVALLATION, or line of countervallation, a trench with a parapet, made by the besiegers, betwixt them and the place besieged, to secure them from the sallies of the garrison; so that the troops which form the siege, are encamped between the lines of circumvallation and countervallation. When the enemy has no army in the field, these lines are useless.