It may perhaps appear, that though, could instruments be considered apart, the foregoing explications might serve to show, that they might all be reduced to a place in our series, yet, as they very commonly act in combination, and as, in such instances, the events in which two or more of them issue are the same, it must be impossible to fix with accuracy the order to which each belongs.Thus, a horse and a cart form together an instrument for the transport of goods.The events, therefore, in which both issue, being the same, we cannot measure the part that may belong to each, in any other manner, than by appropriating to each the proportion indicated by their respective costs of formation, and hence they will both appear to belong to the same order, though perhaps they do in fact belong to different orders.But our subsequent inquiries will show, that the great mass of the instruments existing in the same society are, in reality, at about the same orders; and, that instruments acting in combination with other instruments, are almost always at the same orders.This objection is therefore removed, as all instruments acting in combination may thus be considered as one.
Instruments are frequently repaired.The labor or its equivalent, so expended, may be considered, either as a partial reformation of the old instrument, or as the addition of a new instrument to be combined in action with the old one.The same rules therefore, apply to repairs effected on instruments, as to their original formation.
We have assumed, hitherto, that both formation and exhaustion are properties common to all instruments.There is however a class of instruments, that forms an exception to this general rule.An extensive and important class exists, of a nature so peculiar, that the instruments belonging to it are never exhausted, unless in consequence of some revolution in the circumstances of the society.That part of the surface of the earth devoted to agricultural purposes composes this class.The peculiarity arises from every portion of land so employed, forming two distinct instruments.A piece of land, that it may do its part in providing a supply for future wants, must first be rendered capable of culture, and then be cultivated.It is not necessary that he who renders it fit for culture, should also cultivate it, though it commonly happens that both operations are performed by the same individual.
But by whomsoever the operation of converting waste land, into land bearing crops, be performed, two ends are always gained by it, the power of cultivation, and the actual culture.There is this great difference between them, that while the changes produced in a piece of land to fit it for cultivation are lasting, remaining unless some means be taken to do away with them;those that are effected on it by the actual process of cultivation are of short, or at all events, of limited duration.When an individual has converted a portion of morass or forest, into a field fit for the operations of tillage, it does not return again to the state of morass or forest.
He has fitted it for being made an instrument of agriculture, or rather a succession of instruments of agriculture.The farmer, by manuring it, sowing certain seeds in it, and tilling it, forms it into such an instrument.
The changes he thus effects however pass away.The seeds he sows, growing into plants of different kinds, are carried off; the manure yields part of its substance to them, and is in part dissipated; the soil that had been loosened and pulverized by the plough and harrow, is gradually again compacted and hardened, by the effects of the action of the sun and rain.
As far then as it was actually an instrument of agriculture it is exhausted.
But its power of being again formed into such an instrument remains, and the same operations, the same rotation of crops, may indefinitely succeed one another.
The individual who first forms a portion of land into these combined instruments, has probably in view, only the ends to be gained by one of them.His motive to expend labor on the formation of the field, is to fit it for immediate culture.But, he cannot effect this, without also rendering it capable of being cultivated to all succeeding times.The returns, which for this reason it makes in those succeeding times, form what is called rent; and this peculiarity in the nature of this sort of double instrument, is one of the chief causes of the existence of that particular species of revenue.Any portion of land therefore, which bears a crop, considered as regards its fitness for being cultivated, is an instrument of indefinite exhaustign, and will not consequently coincide with the conditions by which the orders in our series are determined.We shall afterwards see, that in every instance it may, notwithstanding, be reduced to a determined place in that series.A portion of cultivated land, considered as an instrument actually subject to the operations of the husbandman, does not differ from any other instrument.
In conclusion, it may be observed that the position in our series which any instrument will occupy, is determined by the following circumstances.
1.The shorter the space of time between the period of its formation, and that of its exhaustion, the nearer will any instrument be placed to the order A, that is, towards the more quickly returning orders.
2.The greater the capacity, and the less the cost of its formation, the nearer will any instrument be to the order A; the less the capacity, the greater the cost of formation, the farther will it be from A.
Generally, the proximity of instruments to A is inversely as the cost and the time, and directly as the capacity.
CHAPTER V.CIRCUMSTANCES DETERMINING THE AMOUNT OF INSTRUMENTS FORMED.
