From a consideration of the foregoing, it appears that the maximum frontage is justifiable, when a force whose flanks are secure, occupies a position prepared for defense, or acts as a reserve and is to bring about a decision which has been prepared by other troops. On the other hand, the maximum distribution in depth is necessary for a force acting alone in attack with both flanks exposed. Between these two extremes lie many intermediate degrees, and it is therefore impossible to lay down hard and fast rules for the frontage of an attacking force. The German Infantry Drill Regulations (par. 373) accordingly fix the frontage of a company in attack at 150 m. and that of a brigade of six battalions at 1500 m. It is impossible to give a definite ratio of effective strength to combat frontage. Thus, while in attack a company puts into the line about 1.3 rifles per meter of its front, the brigade employs 4 rifles per meter, and the larger units a proportionally greater number. The necessity for distribution in depth increases with the size of the force and with the number of units composing it.
In a company, for example, a platoon is sufficient to fulfill, within certain limits, all the functions of a reserve, while in a larger force the duties of a reserve are so complex that each task (protecting the flanks, reinforcing the firing line, giving the impetus for the assault, and covering the assembling and re-forming of the attacking force) must be assigned to a separate unit. Moreover, the duration of a combat, and, in conjunction therewith, the necessity of reinforcing the firing line and covering the flanks, increases with the size of the force. During protracted periods of peace, one is too much inclined to underestimate the wastefulness of a battle and the necessity for reinforcing the fighting line; one cannot understand why 5 to 6 men will not suffice, during the course of a combat, for a front wherein only one man can use his rifle. From the foregoing it follows that the frontage does not increase in proportion to the number of men. Thus, an army corps would not occupy a front four times that of a brigade, or twice that
