We think, therefore, that we cannot go beyond acknowledging generally the influence of a base on military enterprises, that at the same time there are no means of framing out of this maxim any serviceable rules by a few abstract ideas; but that in each separate case the whole of the things which we have specified must be _kept in view together_. When once arrangements are made within a certain radius to provide the means of subsisting an army and keeping it complete in every respect, and with a view to operations in a certain direction, then, even in our own country, this district only is to be regarded as the base of the army; and as any alteration of a base requires time and labour, therefore an army cannot change its base every day, even in its own country, and this again limits it always more or less in the direction of its operations. If, then, in operating against an enemy’s country we take the whole line of our own frontier, where it forms a boundary between the two countries as our base, we may do so in a general sense, in so far that we might make those preparations which constitute a base anywhere on that frontier; but it will not be a base at any moment if preparations have not been already made everywhere. When the Russian army retreated before the French in 1812, at the beginning of the campaign the whole of Russia might have been considered as its base, the more so because the vast extent of the country offered the army abundance of space in any direction it might select. This is no illusory notion, as it was actually realised at a subsequent time, when other Russian armies from different quarters entered the field; but still at every period throughout the campaign the base of the Russian army was not so extensive; it was principally confined to the road on which the whole train of transport to and from their army was organised. This limitation prevented the Russian army, for instance, from making the further retreat which became necessary after the three days’ fighting at Smolensk in any direction but that of Moscow, and so hindered their turning suddenly in the direction of Kaluga, as was proposed in order to draw the enemy away from Moscow. Such a change of direction could only have been possible by having been prepared for long beforehand. We have said that the dependence on the base increases in intensity and extent with the size of the army, which is easy to understand. An army is like a tree. From the ground out of which it grows it draws its nourishment; if it is small it can easily be transplanted, but this becomes more difficult as it increases in size. A small body of troops has also its channels, from which it draws the sustenance of life, but it strikes root easily where it happens to be; not so a large army. When, therefore, we talk of the influence of the base on the operations of an army, the dimensions of the army must always serve as the scale by which to measure the magnitude of that influence.