Subsistence

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Almost all old wars consist of single unconnected enterprises, which are separated from each other by intervals during which the war in reality either completely ceased, and only still existed in a political sense, or when the armies at least had removed so far from each other that each, without any care about the army opposite, only occupied itself with its own wants.

Modern wars, that is, the wars which have taken place since the Peace of Westphalia, have, through the efforts of respective governments, taken a more systematic form; the military object, in general, predominated everywhere, and demands also that arrangements for subsistence shall be on an adequate scale.
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The modern method of subsisting troops, that is, seizing every thing which is to be found in the country without regard to meum et tuum, may be carried out in four different ways: that is, subsisting on the inhabitant, contributions which the troops themselves look after, general contributions, and magazines. All four are generally applied together, one generally prevailing more than the others: still it sometimes happens that only one is applied entirely by itself.

1 Living on the inhabitant, or on the community, which is the same thing

If we bear in mind that in a community consisting even as it does in great towns, of consumers only, there must always be provisions enough to last for several days, we may easily see that the most densely populated place can furnish food and quarters for a day for about as many troops as there are inhabitants, and for a less number of troops for several days without the necessity of any particular previous preparation.
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The conclusion to be drawn from this hasty glance is, therefore, that in a moderately populated country, that is, a country of from 2000 to 3000 souls per twenty-five square miles, an army of 150,000 combatants may be subsisted by the inhabitants and community for one or two days within such a narrow space as will not interfere with its concentration for battle, that is, therefore, that such an army can be subsisted on a continuous march without magazines or other preparation.
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2 Subsistence through exactions enforced by the troops themselves

If a single battalion occupies a camp, this camp may be placed in the vicinity of some villages, and these may receive notice to furnish subsistence; then the method of subsistence would not differ essentially from the preceding mode. But, as is most usual, if the mass of troops to be encamped at some one point is much larger, there is no alternative but to make a collection in common within the circle of districts marked out for the purpose, collecting sufficient for the supply of one of the parts of the army, a brigade or division, and afterwards to make a distribution from the common stock thus collected.

The first glance shows that by such a mode of proceeding the subsistence of a large army would be a matter of impossibility. The collection made from the stores in any given district in the country will be much less than if the troops had taken up their quarters in the same district, for when thirty or forty men take possession of a farmer’s house they can if necessary collect the last mouthful, but one officer sent with a few men to collect provisions has neither time nor means to hunt out all the provisions that may be stored in a house, often also he has not the means of transport; he will therefore only be able to collect a small proportion of what is actually forthcoming. Besides, in camps the troops are crowded together in such a manner at one point, that the range of country from which provisions can be collected in a hurry is not of sufficient extent to furnish the whole of what is required. What could be done in the way of supplying 30,000 men, within a circle of five miles in diameter, or from an area of fifteen or twenty square miles? Moreover it would seldom be possible to collect even what there is, for the most of the nearest adjacent villages would be occupied by small bodies of troops who would not allow anything to be removed. Lastly, by such a measure there would be the greatest waste, because some men would get more than they required, whist a great deal would be lost, and of no benefit to anyone.