Our cavalry keep, as a rule, but little in touch with such matters. The new "Field Service Manual" introduces the idea of offensive and defensive screens, but the cavalry lack experience in them. Offensive screening is usually accepted, it appears, at all events, at the outset, as being somewhat similar to reconnaissance duties. Real screening is but seldom practised, as operations only last a short time, and usually end with a cavalry encounter, entailing a lapse into the usual set piece.
With regard to these exercises, I would point out that defensive screening, combined with natural obstacles, and possibly with the assistance of the other arms, is much more effective than the offensive method, and therefore deserves more attention, and, further, that there is a considerable difference between a reconnaissance and an offensive screen.
In a reconnaissance an advance is made in the direction which the army commander considers to be most important, and it is left to the enemy's cavalry to oppose this advance. In offensive screening, on the other hand, the enemy must be found before he can be attacked and beaten. An advance would naturally not be risked in a direction that would avoid the enemy's cavalry, and thereby afford it the opportunity of approach against the main army. This should be prevented at all costs. An advance must consequently not be made until information has been obtained from patrols or scouts regarding the position and the line of advance of the enemy's cavalry. Then a determined attack should be made on the cavalry, the force being concentrated as much as possible for this purpose. It is only after this attack has been successfully carried out that the real screening work begins.
The two main points that should be observed when carrying out such exercises are therefore: (1) no advance should be made until the enemy's line of advance has been discovered; and (2) the forces should be distributed, after the defeat of the enemy, on a broad front, in accordance with the requirements of the screening duties, while the enemy's beaten cavalry must be carefully watched, to prevent its further activity.
With regard to defensive screening, it is necessary above all, first, to occupy with sufficient strength all passages over the natural obstacle that has been selected, and to effect a tactical disposition of the forces that will enable them to do a maximum of work with the expenditure of a minimum of strength, making the greatest possible use of field entrenchments; secondly, to so dispose the reserves that they will be quickly available to strengthen any threatened point; and lastly, to arrange a system of communication along the whole screening-line, employing any suitable technical appliances in such a manner that the system will continue to operate even though the enemy's patrol should break through the line. It must be possible also to communicate quickly and safely to the troops in rear, so that any detachments of the enemy that might break through the line may be intercepted. The cavalry telegraph, in fact any kind of telegraph, is the least sure method of communication, particularly in the enemy's country, owing to the ease with which it can be cut. There must, at any rate, be other means of rapid communication besides the telegraph, such as flag signals or the light-signal.
In screening work, balloons are often very useful for discovering the direction in which the enemy is advancing; they are more suited to stationary work, especially behind a protected area, than to active operations. The reconnaissance and the action of the cavalry could then be based on the information received from the balloons. It will, unfortunately, seldom happen during such manœuvres that a balloon is available, but all the necessary technical appliances for communication should certainly be at hand.
The value of all these exercises, especially in the case of reconnaissance, is largely dependent on the manner in which the enemy is represented. The best plan is, of course, to place real troops at their full strength opposite to one another, but this is scarcely practicable, on account of the expense entailed. Even the Imperial Manœuvres do not faithfully represent modern armies and distances, but only reproduce portions of great operations on a reduced scale. The fact of the matter is that it is impossible, in time of peace, to set on foot anything approaching the number of men, or to cover anything like the extent of country, necessary to at all correspond with the conditions of modern warfare. The only feasible plan is to indicate columns of the army, and even large bodies of cavalry, by flagged troops; but it is well to place real troops at the head of these columns, so that they may form the vanguard and may send out the full number of patrols and outposts, at all events to the front. The reconnoitring organs would thus, at any rate to the front, be confronted by an enemy disposed as in real warfare. I need hardly say that both sides should send out these reconnoitring detachments, as far as possible at full strength; no advantage can possibly be derived from the exercises if this is not done.
It is also very important to put the divisional cavalry into the field, where possible at full strength, as the difficulties that beset the reconnoitring patrols will only then become apparent. This divisional cavalry need only send out a limited number of these patrols, as they are, as a rule, not absolutely necessary in such exercises, but the work of screening should receive careful attention. The division should therefore be surrounded by a screen of security patrols, and all points from which the enemy's patrols might observe the columns should be occupied. If these columns are on the march, the security patrols should advance in "bonds successifs," together with the divisional cavalry, from one line of observation to the next, and thus prevent any possible reconnaissance on the part of the enemy. If the ground on the line of advance is suited to defensive screening, this method should be adopted, and all the enemy's patrols and despatch-riders seen should be hunted down. When the hostile reconnoitring patrols have been driven back behind their own screens or outposts, measures should be taken to prevent their re-issue. If the enemy's patrols endeavour to remain for the night in the vicinity of the troops they wish to keep under observation, they should, if possible, be attacked and captured. When operations are being carried on in friendly country, it will be well to ensure the co-operation of the inhabitants in obtaining information regarding the movements of the enemy's troops. There are always old soldiers to be found among the civil population, who would interest themselves in the matter if called upon by the local magistrates to assist, and who would certainly do their utmost to help their own countrymen and to hamper the enemy. Care should, of course, be taken not to go too far in this direction, as unfortunate consequences might possibly result.
It will also be well to send numerous umpires with the army columns and their vanguards, and with the divisional cavalry, and also along the main roads, whose task it will be to conduct the manœuvres as nearly as possible on the lines of real warfare. Umpires should also be attached to reconnoitring patrols and squadrons, at any rate to those of one side, so that there may be an impartial witness of any encounter. The appointment of these umpires would have the further advantage of providing work at the important points for a larger number of officers, who would thus learn more than they would do when simply marching with their units.
When the various portions of the army are to be represented by flags, each flag should be made to represent a company, a battery, or a squadron, but the flags should be so disposed as to oblige patrols to estimate the strength of the columns by their length, as in war there would not often be time or opportunity to count the separate tactical groups of the enemy. Too few flags should not, however, be used, but rather as many as possible, so as to produce the effect of a continuous column on the move, infantry and artillery being clearly indicated. The detachments of cavalry that would in actual warfare be stationed at different points along the column might with advantage be represented by real cavalry, who would be able to pursue the enemy's horsemen. Artillery patrols might also relieve the cavalry of this duty, and, in difficult country, march on the flanks of the column, thereby making matters more difficult for the hostile scouts. All measures of this description would greatly assist in giving to manœuvres the character of real warfare, and in increasing the difficulties in the way of the far-too-easy peace-time reconnaissance.