The order of battle.
When large bodies of men approach for battle, only a proportional part of them are engaged at a time — they are replaced by another similar force — the progress of the battle is by successive engagements. On the genius and judgment of the chief will depend the character of the action, whether it shall be defensive or offensive.When an army awaits the attack, it takes its position and forms its line of battle according to the nature of the ground, and the character and strength of the enemy's force. If offensive, the main thing is to seize upon the decisive point of the field. This point is determined by the configuration of the ground, and the position of the contending forces, or by a combination of these. The defence is considered the stronger form of actions of war, and a skillful General will take advantage of favorable circumstances to change the defensive into the offensive. Military writers lay down twelve orders of battle. A description of these would be too long and too complicated to interest the reader. Which of these should be followed, must be decided by the chief himself on the ground, where all the circumstances may be duty considered. To concentrate a superiority of forces at the decisive point is the principal purpose. This point is in the flanks or in the rear of the enemy. To do this the skill of the General is brought into requisition.
On the field of battle, the Infantry is divided into three bodies — in advanced guard, a main body, and a reserve. These three bodies are separated from each other by intervals, which will depend upon the nature of the ground — the advanced guard occupying the front, the main body at a distance from one hundred and fifty to three hundred paces in its rear, and the reserve at a like interval in the rear of the main body. The troops composing these three bodies will be formed either in columns of battalions, or be deployed. For an attack, for evolutions, or for defence against cavalry, the formation of columns of battalions is the best. To repel the enemy's attack by a fire, and to present a less favorable mark to the enemy's Artillery, the battalion should be deployed. The reserve should be composed of the most reliable troops, and should, if possible, be kept masked from the enemy's view and fire, until called into action. The time for engaging the reserve is either when the enemy has been shaken in its attack by the resistance offered by the main body, or when the main body is unable further to resist the enemy's efforts.
The cavalry is usually placed in the rear of the infantry, and should be masked from the fire until the moment arrives to bring it into action. The habitual formation of cavalry for the attack is a line of two ranks, with a reserve or support in rear. Cavalry should wait patiently until a way is prepared for its action by the fire of artillery on the enemy's infantry; or when the infantry is fatigued or exhausted; or when the infantry is in motion, so as to surprise it before it can form to receive the attack. It should direct its charge on that part of the enemy's infantry, where it will be itself exposed to the least column of fire. If the infantry is in a line, its charge should be made on one of its flanks; if in square, on one of the angles of the square.
The manner of placing the artillery, and its employment, must be regulated by relative importance under given circumstances with respect to the action of the other arms. In defence, the principal part is usually assigned to the artillery; in offensive movements the reverse generally obtains. In defence the batteries should be distributed along the entire front of the position occupied. The distance between the batteries should not be much over 600 paces. When the wings of a position are weak, heavy batteries should be placed to secure them. A sufficient number of pieces should always be held in reserve for a moment of need. In the attack the heaviest pieces should be placed on the flanks of the ground occupied by the assailant, or on the centre if more favorable to the end to be obtained. In all the movements of the batteries great care should be taken not to place them so that they shall in the least impede the operations of the other troops.
