time in the north-west of France and on the Belgian frontier.
§ 87. Previous Improvements in Weapons and Armament. Question of Depth of Fighting Line. It is of interest to note that, previously to the arrival of the aeroplane, most of the improvements of weapons and armament have tended to favour the attack and to render defence more difficult. During the last three or four centuries we have seen the value of permanent defences gradually diminish, as constructional improvements and scientific methods of usage have rendered the Artillery Arm more and more deadly. Of more recent times we have witnessed the result of the increased effectiveness of fire-arms generally in the greater concentration that can be effected on any given point in a field of battle. In other words, the depth of the line has been increased by the greater range of small-arms, and it may to-day be increased almost indefinitely by the employment of artillery of heavier and heavier calibre, with correspondingly increased range. Such increase in the depth of the line only becomes of general value when, as in the present war, the number of men per mile of front is great, and more men are available than can be effectively employed in the trenches or infantry supports. Any additional numerical strength must then be assigned to the Artillery Arm, and the greater the supply of men (in other words, the greater the density of the line), the greater becomes the relative importance of Artillery: then the heavier and longer range should be the artillery brought into action, in order to ensure that the weight of numbers shall tell, in some degree at least, in accordance with the n-square law. It would seem that this is a point which has been very fully realised by the German Staff. In our own experience it is certain that the Boer War, owing to the comparative openness of the country
129
