When a battalion is formed into a column for the purpose of an attack, it is called a column of rnanreuvre ; and when so formed in order to move along a road or through a defile, a column of route. In either ease the column may be in open order, at half or at quarter distance, or in close order ; and in the first formation the column, of course, occupies in length an extent of ground equal to that which it occupies in line, minus the length of the first division. Columns at half or at quarter distance, or at close order, have the convenience of moving upon less space than the open column, with equal capacity of forming in any manner that may be required for resisting an attack ; and their compact order enables them to avoid the evils attending the loss of distances which may occur with an open column, from the inequalities of the ground.
The battalion in line may be formed into a single or double column : the former upon or in rear of either flank company, and the latter upon the two centre companies or the two centre subdivisions. In either case the column is equally fit for its purpose, and the preference of one to the other must depend upon the ground or upon the point to which the movement is to be directed : the single column, however, can always be diminished to the smallest degree, according to the defile ; whereas the double column, if much diminished, may be in danger of becoming disordered by the intermixture of the files. For an attack, the column formed on the centre of a battalion can be more rapidly brought to bear upon the required point than a column formed on one of the wings, seeing that the divisions in line have but half the distance to march through in order to arrive at their places in the column, and a corresponding advantage is enjoyed when the battalion has to deploy from column into line.
It is to be observed that the front of a column should never be unnecessarily contracted, and battalions should be so instructed as to render it indifferent whether the first or second rank is in front, or whether the right or left flank division (of the line) is at the head of the column ; but occasions may occur in which the order of battle is to be reversed, and then the divisions must necessarily change their positions by countermarching.
A battalion in column at open order is formed in line to the front by the rear companies wheeling backwards an eighth of a circle on their right or left, according as the right or left is in front, and then moving up in this direction the inward flank comes up to the alinement or flank of the halted company, then wheeling aneighth of a circle to the left or right, brings them up into line—ur if the line is tole formed to a flank by merely causing the divisions to wheel upon their respective pivots; but a close column of companies, haviog its head already in the alignement, is deployed by causing the several divisions to move out by files to the right or left parallel to the alignement; each division having got beyond that which was in front of it turns to the left or right, and then marches up to its place in the line. The deploy
ment may take Owe upon any one of time companies; should it bo on one of the rear companies, it has to remain halted till its front is clear, when it moves up at a double—the other companies halting in the same way till their front is clear, and then moving up.
Echellon movements are performed when it is required to advance or retreat obliquely, and when a chauge is to be made in the position of a line, corresponding to a wheel of the whole about some given point : the movements are made to the front when an enemy'a flank is to be turned, and to the rear when it is required to cover the flank of the line itself. Echelon movements are the safest that can be adopted by troops in presence of the enemy, as they have the advantage of preserving a general front during the march. A direct echellon, as it is called, may be formed by the different companies or subdivisions marching from their position in the lino towards the front or rear, keeping parallel to that position, and halting successively when arrived at the required distances. The oblique echellon is formed by causing the d fferent companies or subdivisions to make a wheel upon their pishate through any angle less than a right angle, but generally not more than one-eighth of it ; the position and parallelism of the divisions being ensured by causing a non-commissioned officer of each division to place himself, as the case may require, before or behind the eighth file from the pivot, then by his taking paces of 30 inches (the regulation pace) on the arc of a circle, of which the pivot is the centre, he may indicate an alinement of any portion of the circle I. or !, that may be required, every 2 paces giving of the circle; the division is then to wheel lip to the place where he halts.