In the first place, I think that what the "Field Service Manual" says as to offensive screens requires some explanation. Strong cavalry will be concentrated to keep the enemy at a distance from our own army. In addition to this, strong patrols and even cyclist detachments advance along all roads in order to throw back the hostile patrols. These arrangements can only apply, as a rule, for portions of the army cavalry. They presuppose, especially if the front of the modern army is to be screened, a mass of cavalry which could with difficulty be found from the divisional cavalry. By such methods, moreover, as long as strong cyclist detachments are not available for blocking the road communications, a cause of dissension will always arise as to how much strength can be used for blocking the roads and how much concentrated for battle, all the more so as the divisional cavalry can only with difficulty be used in this kind of screen.

The latter must, as we have seen, remain more or less locally tied to the division. The army cavalry, however, if it will undertake an offensive screen, must advance against the enemy, seek him out, force him back as far as possible from our own army, and endeavour to defeat him. For this task complete freedom of movement is necessary—not only for itself, but also for the screen of patrols that will accompany it. The divisional cavalry will thus generally only be able to form a second screening line behind the veil formed by the advancing army cavalry, and will not be in a position to spare for it patrols for the blocking of roads. Nor is it at all clear where the cyclist troops mentioned are to come from.

I am therefore inclined to think that the procedure advocated by the "Field Service Manual" can only be carried out in exceptional cases; and it would perhaps be advisable to alter it somewhat.

The principal task of the offensive screen is, according to my opinion, to defeat the hostile cavalry; and for this object all available force must be concentrated, for one cannot be too strong upon the field of battle. Even such cyclist detachments as are available will be best used by bringing them up for the fight. The blocking of roads, on the other hand, will, as a rule, be only undertaken when the enemy's cavalry has been beaten and thrown back. The screen of patrols can then be strengthened. But it must be quite clearly understood that troops are not to be simply disposed in a cordon; but that a sufficiently strong force must still remain in touch with the beaten enemy in order to prevent him, at all events, from taking up the offensive again, and breaking through the screen.

Until this moment of victory over the hostile cavalry the duties of screening must be left to the reconnoitring organs and to the divisional cavalry of the army which is following in rear of them.

According to the principles laid down in the "Field Service Manual" it is to the divisional cavalry that the task invariably falls of screening the movements of its division. I think that these duties cannot always be clearly regulated according to the idea of an offensive or defensive screen; they will more often be of a mixed nature. As far as its strength will admit, the divisional cavalry will endeavour to carry out the task by pushing back, by fighting, the hostile reconnoitring patrols and detachments before these have succeeded in gaining observation. As it is more or less locally confined to its own front, and will certainly often have to do with an opponent of superior strength, it will, on the other hand, frequently be obliged to join battle for favourable localities dismounted, supported whenever possible by machine-guns and cyclists from the infantry. In situations where the divisional cavalry cannot undertake an offensive fight against the superiority of the enemy, and can find no points d'appui in the terrain, it must try all the more to block the roads with patrols which will attack all hostile patrols with the utmost determination, and endeavour to capture their despatch-riders. The divisional cavalry must show the greatest boldness and judgment if it will carry out this task. The great importance of its rôle in the army here again becomes obvious.

The army cavalry will only undertake an offensive screen when the army is advancing, and where the country does not afford suitable localities for the establishment of a defensive screen.

Such a screen (defensive), which can eventually be pushed forward from one area to another, is without doubt, as is emphasised by the "Field Service Manual," of much more use than an offensive screen.

Of great importance in a defensive screen is, first and foremost, the nature of the obstacles on which it is based. Watercourses and canals, which can only be crossed by bridges, form the best of these. Extensive woods, however, lend themselves easily to the purpose. They are doubtless, for cavalry patrols, a most unpleasant obstacle, as view is restricted in them, and an ambush may lurk behind every tree. In the campaign of 1870-71 the German cavalry patrols were, as far as I could ascertain, quite unable to penetrate into the wood of Orleans and that at Marchenoir. These woods, by their mere existence, formed an effective screen.

To utilise woods for this purpose it will be necessary, according to the circumstances, the depth and nature of the wood, to post the fighting detachments of the screening line either at the exit of the defile on the enemy's side or more towards the defender's side on the inner edge of the wood, if they can there find a good field of fire. In any case the opposite edge of the wood should be occupied by observation-posts; in order, in the first case, to get knowledge of and to neutralise any hostile patrol which may, in spite of all difficulties, have penetrated the wood, as soon as they emerge; and, in the second, to get early information of the entrance of hostile detachments into the wood, and to be able to hinder, report, and observe their further advance.