Assaulting and Occupation Troops. Experience has suggested to the Allies to divide their fighting troops into army corps for assault and army corps for occupation.
Once the objectives are attained and strongly held, the assaulting troops are replaced by the occupation troops that arrive fresh on the ground. Their task, though one of defence, is often hard. They have to remain a long time in the first lines, exposed, by reason of the new German methods, to frequent and severe bombardments, and obliged to repel numerous counter-attacks.
The generals commanding-in-chief are the exclusive judges of the part the different army corps will have to play, but, in our opinion, there is one principle which must never be ignored in war. In the army, as well as in the battalion and in the company, it is the duty of the Chief to select for action, irrespective of any rotation of service, that element of the troops under his command which he deems the one most likely to achieve the desired result.
What we have said concerning the use of the artillery, the armament of the infantry, the distribution of the infantry in the division and the trenches of attack, will enable us to give an exact idea of the physiognomy of an offensive action and of its preparation.
Offensive Engagements. Their Preparation. The preparation of attacks in a war of position is a long one. On account of the work it necessitates it is very difficult to conceal these preparations on the front from the opposing aviation, and also, alas! from the curiosity of the rear.
An attack can be determined upon only by order of the General-in-Chief, who decides where and on what front it shall be made. He gives his instructions to the General in command of an army group, who, according to circumstances, employs one or several of his armies for the operation. Each General commanding an army prepares an order of operation for each of his army corps, and so on, until the precise instructions reach the elements of the first line.
The preparation then commences. It consists in establishing on the terrain under the protection of the batteries:
1st. The new lines of the infantry, and, if necessary, the communications between these lines;
2d. The location of the artillery of all calibres;
3d. The organization of the posts of command;