There is in every camp some one essential point, or hinge, which may be called the key of it ; and on which the strength of it most immediately depends ; while you keep this, the enemy has nothing, and when you lose it, all is lost. The same holds good as to po sitions. The choice of this point, with regard to posi tions, depends entirely on, and must be regulated by, the object which the general has in view ; by the situ ation of his magazines, and by the number and species of his troops, that he may not only have a good posi tion, but likewise a good field of battle, in case he is attacked. On the talent of discovering these points, depends the science of camps and positions, and the method of attacking and defending them.* We may conclude this branch of the subject with the general observation, that no position, however strong, can secure an army remaining immoveable within it from being overwhelmed, or turned at one or other of its ex tremities ; and that the only certain method to prevent such a misfortune is by manoeuvring in the same sense as the enemy, that is offensively, and by threatening his own line.
An army ought never to make a movement without having some object in view, and measures should always be taken to secure that object with as much safety and convenience as possible. A movement may be made forwards, or towards the enemy ; to the rear, or from the enemy ; aside, in our own, or, at the same time, into the enemy's parallel : and the object of all these movements may be, to give battle ; to avoid a battle ; to change our camp for the better maintenance of the troops; to pre vent such a design in the enemy ; to entice him into some other quarter, or prevent him from establishing himself there ; for the purpose of passing a river or defile, or of preventing the enemy from passing it ; to invest a for tress, or prevent the enemy from investing one ; with the view of making a feigned march, in order to deceive him, and then to attain our object by another movement.
In every movement, two things are especially requi site to enable us to attain our object. In the first place, celerity ; and, secondly, good arrangements. Celerity is of two kinds ; it consists either in the rapidity of the movement itself, or in its continuance. Both are called forced marches. Cavalry perform a forced march in the one way, and infantry in the other. But as both are destructive to men and horses, they ought never to be undertaken without urgent necessity ; and a skilful ge neral will not often be obliged to have recourse to them. The arrangements consist, first, in lightening the army, by removing all heavy carriages that can be dispensed with ; secondly, in preparing the roads ; and, thirdly, in the occupying of posts, and sending out detachments, in order to facilitate or secure the march.
A movement is rendered secure, 1 By concealing it from the enemy ; which may be done by breaking up suddenly, by marching at night, by avoiding every thing that can betray the march, such as drawing in the posts, extinguishing the fires, striking the tents, Scc. or by de ceiving the enemy with illusory appearances, such as smoke, dust, &c. 2. By providing against every acci dent. For this purpose, the ordinary dispositions for a march, which we formerly noticed, are to be observed ; and we may calculate in what points of the march we can take up positions, and how much time will be re quired to place the troops in order of battle in every point ; posts and detaehments may be sent out, in order to obtain early intelligence of the enemy's motions, that we may have time to form in order of battle in evy ry such position. \Vc may cover the march by ore upying the passes till ough which the enemy could reach us. or such objt cts, under the lir. . of which the enemy would obli,.;eil to pass, s. ounl he e. ish to att tck the runty in march ; or we to.) pl is LIN' dry in such a situation as woual eu .bie t.ic:n t i fill npoti the flank of the enemy out hissppiotcil. For the (0111cnienct• of the in itch, it is m cessary that we have good roads, and make no cir nos, nor expose the troops to any unnecessary fa ti ut \Ve shall afterwards have occasion to treat of the man It forwards, for the purpose of giving battle, as well as of the nnivements in p ss lg and defending defies. Lt starching to the rear, in order to avoid a battle, we must pay pat ticular attention to our own situation and circumstances, and to the probable enterprises of the enemy. If he be quit., close to us, and can immediately attack us, we must take every possible precaution to conceal our march, and to perform it in safety, espe cially if we have a discouraged army. All the heavy at finery and baggage must be sent to a distance before us ; the march must be performed rapidly, but without disorder ; and we must endeavour, before the enemy can attack us, to gain some defiles into which he cannot fol low us. If he be at such a distance from us, that he cannot follow us with his whole army, but only harass us with a corps of cavalry and dragoons ; in that case we may, according to circumstances, diminish the hard ship and fatigue which the troops would otherwise have to undergo.