If, therefore, complete uncertainty reigns as to the enemy's strength, it will be better at first to operate tentatively with a portion of the force until an opinion can be arrived at as to whether the decisive attack can be ventured on. Energetic contact with the enemy by fire action will generally soon clear up this point.
The view that a gradual and judicious employment of force is not in accordance with the principles of cavalry action (430)[30] can only be justified in the case of the pure cavalry combat mounted. This, however, in my opinion, should only be determined upon if the enemy's strength is known, at all events to some degree. I do not share the view of the Regulations that, if uncertainty reigns as to the strength and intentions of the enemy, freedom of action can be preserved, even in the mounted combat against cavalry, by the use of formations in échelon (424).[31] This is only possible by a protracted action in which gradual reinforcements are used, and only in such a manner can the enemy be forced to disclose his strength and intentions. A protracted fight, however, can only be carried out by fire action. A mounted advance, whether made in échelon or otherwise, cannot alter the rapid nature of a cavalry fight, and will not allow of sufficient time being gained to form a proper appreciation of the enemy. Échelon formations lead at best to eccentric attacks and thereby to unfavorable tactical situations.
If the situation is to be cleared up by fighting, fire action must be employed, and as soon as this occurs, whether on the part of the enemy or oneself, a gradual employment of force is not only no disadvantage, but is demanded by the circumstances. For at first the fight must be carried out from depth; the Napoleonic "Je m'engage et puis je vois"[32] holds good; one's own main force will only be engaged when the strength and intentions of the enemy become in some measure known. It will, however, be advisable in all cases to keep a strong reserve in hand until prepared to advance to a well-considered and planned attack.
The passage of defiles, also, is scarcely likely to be undertaken in serious war in the manner so often seen at manoeuvres. Here the chief matter for consideration is generally to keep one side as far from the defile as possible, in order that the passage of the other may be possible. Such tender solicitude is scarcely to be expected of a real enemy, and it will, I opine, scarcely occur to anybody in war to attempt a defile without preparation, and to advance on the farther side against an enemy whose strength, as is generally the case in war, is unknown, thereby running the danger of being thrown back on the defile and of suffering enormous loss. Such a danger, to which the whole force is exposed, would certainly only be incurred when the gravest necessity compelled. What the Regulations say in this respect (434)[33] has, to my mind, but a limited practical significance.