Similarly, when advancing in separated columns, it will be well to advance from one defensive section to another in rushes, and not to go beyond any one of these until fairly assured that one can reach the next without encountering the enemy's Cavalry. If one should have the misfortune of being surprised in a district which affords no points of support, then one must retire to the next best one in order to give the adjacent columns time to swing in against the enemy's flanks. The sound of the guns will be indication enough to these to hasten their pace. The more important it is, therefore, to march to the sound of the guns in order to save time, the more careful must one be in opening fire without sufficient cause. On the one hand, the side which wishes to attract support will not be satisfied with a few rounds, but will endeavour by continuous and heavy firing to make the danger of his situation evident; on the other, the adjacent columns will only then be justified in approaching if they are convinced that it is not a mere matter of local and transitory advantage. The Cavalry Commander must keep, therefore, a firm hand over his guns, and never allow these to come into action without express sanction, except in extreme necessity. Generally, the batteries should always march with the advance or the rear guard in order to break down rapidly any minor resistance, and to make the fullest use of such short opportunities as may arise for the utilization of their full power. The application of these principles is, of course, much simpler when it is possible to keep the several columns close together on a convenient group of roads, all running fairly near to one another. The disadvantages which then arise make less demand on the skill of the Leader, but more on the necessarily cramped form of the disposition which, as we have above pointed out, he is compelled to adopt. For every operation, in fact, except the direct attack, there is a certain degree of extension, which favours the immediate purpose the most, and this depends on the shape and nature of the ground; but one has always to resist the temptation to dispersion which arises, particularly when it is necessary to keep in mind the solution of several possible problems. Only very occasionally will it be expedient to divide one's troops to meet every emergency.