Generally speaking, such engagements will only be those which are fought out on foot. The more open the country, the closer the enemy, and the greater the number of troops which have already been thrown into the fighting-line, so much the more difficult will it usually be to break off the fight. The circumstance also as to whether the led horses are mobile or immobile, and their position, will naturally influence the decision. On the other hand, it is easier to extricate the force after some success has been gained; whether it be that a hostile attack has been repulsed, or that our own troops have made a successful counter-stroke. History teaches us that at such moments there is generally a lull, during which the opponent is obliged to bring up fresh troops or to make fresh tactical dispositions. Even under such favourable conditions, however, it will generally be impossible to break loose from the enemy without suffering heavy loss. In defence, if the ground is especially favourable, it will certainly be possible at times to extricate a force without considerable loss. If it can rapidly withdraw from the firing-line and retire covered from pursuing fire, the whole force may under certain circumstances simultaneously evacuate a position, that is to say, if the enemy is still so far distant that he is unable to employ pursuing fire until the defender has reached a place of safety. How seldom, however, will such be the case! Small detachments will generally have to be sacrificed to secure the retreat of the main body. This means that various especially strong supporting points in the position will be occupied, and the force will withdraw under cover of them. Military history offers us repeated examples where the attacker makes desperate endeavours to overpower such points, and in so doing forgets to pursue the withdrawing masses of the defender's troops. This, for example, was the part played at the battle of Weissenburg by Geisberg Castle and Schafbusch, and the château with its enclosed park at the battle of Coulmiers. Under cover of these points, against which all the efforts of the French were concentrated, the defenders were able in both cases to withdraw so slightly molested that even touch with them was completely lost. The defence of such supporting points, which must be conducted with the utmost obstinacy, frequently ends in capture, but the end gained is worth the sacrifice. If the endeavour is made to withdraw the whole line of defence simultaneously under circumstances where it is possible for the attacker to bring to bear an effective pursuing fire from the captured position, loss will generally be much greater than that which would be deliberately incurred in arresting the pursuit.