On that account we make it the subject of our special consideration, and at this stage before we enter upon the special ends which may be bound up with it, but which do not essentially alter its character if it really deserves to be termed a battle. If a battle takes place principally on its own account, the elements of its decision must be contained in itself; in other words, victory must be striven for as long as a possibility or hope remains. It must not, therefore, be given up on account of secondary circumstances, but only and alone in the event of the forces appearing completely insufficient. Now how is that precise moment to be described? If a certain artificial formation and cohesion of an Army is the principal condition under which the bravery of the troops can gain a victory, as was the case during a great part of the period of the modern Art of War, _then the breaking up of this formation_ is the decision. A beaten wing which is put out of joint decides the fate of all that was connected with it. If as was the case at another time the essence of the defence consists in an intimate alliance of the Army with the ground on which it fights and its obstacles, so that Army and position are only one, then the _conquest_ of _an essential point_ in this position is the decision. It is said the key of the position is lost, it cannot therefore be defended any further; the battle cannot be continued. In both cases the beaten Armies are very much like the broken strings of an instrument which cannot do their work. That geometrical as well as this geographical principle which had a tendency to place an Army in a state of crystallising tension which did not allow of the available powers being made use of up to the last man, have at least so far lost their influence that they no longer predominate. Armies are still led into battle in a certain order, but that order is no longer of decisive importance; obstacles of ground are also still turned to account to strengthen a position, but they are no longer the only support. We attempted in the second chapter of this book to take a general view of the nature of the modern battle. According to our conception of it, the order of battle is only a disposition of the forces suitable to the convenient use of them, and the course of the battle a mutual slow wearing away of these forces upon one another, to see which will have soonest exhausted his adversary.