_An_ ARMY _of reserve_ may not improperly be called a general depot for effective service. In cases of emergency the whole or detached parts of an army of reserve are generally employed to recover a lost day or to secure a victory. It is likewise sometimes made use of for the double purpose of secretly increasing the number of active forces and rendering the aid necessary according to the exigency of the moment, and of deceiving the enemy with respect to its real strength. Such was the army at Dijon, before Bonaparte entered Italy. _Flying_ ARMY, a strong body of horse and foot, commanded for the most part by a lieutenant-general, which is always in motion, both to cover its own garrisons, and to keep the enemy in continual alarm. _A naval or sea_ ARMY, is a number of ships of war, equipped and manned with sailors, mariners, and marines, under the command of a superior officer, with the requisite inferior officers under him. ARNAUTS, Turkish light cavalry, whose only weapon was a sabre very much curved. Some are in the Russian service. ARQUEBUSE _a Croc_, an old piece of fire-arms, resembling a musquet, but which is supported on a rest by a hook of iron, fastened to the barrel. It is longer than a musquet, but of larger calibre, and was formerly used to fire through the loop holes of antique fortifications. ARQUEBUSIER, a French term, formerly applied to all the soldiery who fought with fire arms, whether cavalry or infantry. ARRAY, order of battle. See BATTLE-ARRAY. ARRAYERS, officers who anciently had the charge of seeing the soldiers duly appointed in their armor. ARREARS, in the army, were the difference between the full pay and subsistence of each officer, which was directed to be paid once a year by the agent. See PAY. ARREST, a French phrase, similar in its import to the Latin word _retinaculum_. It consists of a small piece of steel or iron, which was formerly used in the construction of fire-arms, to prevent the piece from going off. _Ce pistolet est en arret_ is a familiar phrase among military men in France. This pistol is in arrest, or is stopped. ARREST, is the exercise of that part of military jurisdiction, by which an officer is noticed for misconduct, or put into a situation to prepare for his trial by a general court-martial. ARRESTE of the glacis, is the junction of the talus which is formed at all the angles. ARRIERE, _Fr._ the rear. ARRIERE _Ban_, _Fr._ See BAN. ARRIERE-_garde_, _Fr._ the rear-guard. _En_ ARRIERE--_marche!_ _Fr._ to the rear--march! ARROW, a missive weapon of offence, slender and pointed, made to be shot with a bow. ARROW. See FORTIFICATION. ARSENAL, is a large and spacious building, or number of buildings, in which are deposited all kinds of arms, and other warlike implements; such as cannon, mortars, howitzers, small arms, and every other kind of warlike engines and instruments of death.