ECHELLE, _Fr._ ladder, in civil and military architecture, means a machine, which is made of two side pieces or arms, that receive a certain number of small steps, at equal distances from one another. These _echelles_ or ladders, are of two kinds: large and small. The small ladders are used to descend into the ditches of fortified places, and the large ones for scaling the walls, &c. See SCALING LADDERS. ECHELLON, _Fr._ from _echelle_, a ladder. A position in military tactics, where each division follows the preceding one, like the steps of a ladder; and is convenient in removing from a direct to an oblique, or diagonal line. When troops advance in _echellon_, they almost invariably adopt the ordinary time. Hence to march in _echellon_, may not improperly be said to approach towards any given object by a gradual movement. ECHELLON _movements and positions_, are not only necessary and applicable to the immediate attacks and retreats of great bodies, but also to the previous oblique or direct changes of situation, which a battalion, or a more considerable corps already formed in line, may be obliged to make to the front or rear, or on a particular fixed division of the line. The oblique changes are produced by any wheel of less than the quarter circle of divisions from line, which places them in the echellon situation. The direct changes are produced by the perpendicular and successive march of divisions from line to front, or rear. See _Amer. Mil. Lib._ ECLAIREURS, _Fr._ a corps of grenadiers raised by Bonaparte, in France, who from their celerity of movement were compared to lightning. ECLOPES, a French military term, to express those soldiers who, though invalids, are yet well enough to follow the army. Among these may be classed dragoons or horsemen, whose horses get suddenly lame, and cannot keep up with the troop or squadron. They always march in the rear of a column. ECLUSES, _Fr._ See SLUICES. ECONOMY, in a military sense, implies the minutiæ, or interior regulations of a regiment, troop, or company. Hence regimental economy. ECORE, _Fr._ steep shore. _Côte en ecore_, signifies a very steep descent. ECOUPE, _Fr._ An instrument used by the pioneers. See OUTILS. ECOUVILLON, _Fr._ a maulkin or drag. The spunge made use of to clean and to cool the inside of a cannon, when it has been discharged. ECOUVILLONER, _Fr._ To clean a piece of ordnance before it has been fired, or to cool it after. ECRETER, _Fr._ To batter or fire at the top of a wall, redoubt, epaulement, &c. so as to dislodge or drive away the men that may be stationed behind it, in order to render the approach more easy. _Ecreter les pointes des palissades_, is to blunt the sharp ends of the palisades. This ought always to be done before you attack the covert way, which is generally fenced by them.