On the other hand, through the new method of supplying troops the movements of armies have acquired a new _retarding_ principle. If troops have partly to procure supplies for themselves, which often happens, then they require more time for the service of supply than would be necessary merely to receive rations from provision wagons. Besides this, on marches of considerable duration troops cannot be encamped in such large numbers at any one point; the divisions must be separated from one another, in order the more easily to manage for them. Lastly, it almost always happens that it is necessary to place part of the army, particularly the cavalry, in quarters. All this occasions on the whole a sensible delay. We find, therefore, that Buonaparte in pursuit of the Prussians in 1806, with a view to cut off their retreat, and Blücher in 1815, in pursuit of the French, with a like object, only accomplished thirty miles in ten days, a rate which Frederick the Great was able to attain in his marches from Saxony to Silesia and back, notwithstanding all the train that he had to carry with him. At the same time the mobility and handiness, if we may use such an expression, of the parts of an army, both great and small, on the theatre of war have very perceptibly gained by the diminution of baggage. Partly, inasmuch as while the number of cavalry and guns is the same, there are fewer horses, and therefore, there is less forage required; partly, inasmuch as we are no longer so much tied to any one position, because we have not to be for ever looking after a long train of baggage dragging after us. Marches such as that, which, after raising the siege of Olmütz, 1758, Frederick the Great made with 4,000 carriages, the escort of which employed half his army broken up into single battalions and companies, could not be effected now in presence of even the most timid adversary. On long marches, as from the Tagus to the Niemen, that lightening of the army is more sensibly felt, for although the usual measure of the day’s march remains the same on account of the carriages still remaining, yet, in cases of great urgency, we can exceed that usual measure at a less sacrifice. Generally the diminution of baggage tends more to a saving of power than to the acceleration of movement. CHAPTER XII. Marches (_continued_) We have now to consider the destructive influence which marches have upon an army. It is so great that it may be regarded as an active principle of destruction, just as much as the combat. One single moderate march does not wear down the instrument, but a succession of even moderate marches is certain to tell upon it, and a succession of severe ones will, of course, do so much sooner.