In tracing more particularly the laws which govern the rise and fall of rents, the main causes which diminish the expenses of cultivation, or reduce the cost of the instruments of production, compared with the price of produce, require to be more specifically enumerated. The principal of these seem to be four: first, such an accumulation of capital as will lower the profits of stock; secondly, such an increase of population as will lower the wages of labour; thirdly, such agricultural improvements, or such increase of exertions, as will diminish the number of labourers necessary to produce a given effect; and fourthly, such an increase in the price of agricultural produce, from increased demand, as without nominally lowering the expense of production, will increase the difference between this expense and the price of produce.
The operation of the three first causes in lowering the expenses of cultivation, compared with the price of produce, are quite obvious; the fourth requires a few further observations.
If a great and continued demand should arise among surrounding nations for the raw produce of a particular country, the price of this produce would of course rise considerably; and the expenses of cultivation, rising only slowly and gradually to the same proportion, the price of produce might for a long time keep so much ahead, as to give a prodigious stimulus to improvement, and encourage the employment of much capital in bringing fresh land under cultivation, and rendering the old much more productive.
Nor would the effect be essentially different in a country which continued to feed its own people, if instead of a demand for its raw produce, there was the same increasing demand for its manufactures. These manufactures, if from such a demand the value of their amount in foreign countries was greatly to increase, would bring back a great increase of value in return, which increase of value could not fail to increase the value of the raw produce. The demand for agricultural as well as manufactured produce would be augmented; and a considerable stimulus, though not perhaps to the same extent as in the last case, would be given to every kind of improvement on the land.
A similar effect would be produced by the introduction of new machinery, and a more judicious division of labour in manufactures. It almost always happens in this case, not only that the quantity of manufactures is very greatly increased, but that the value of the whole mass is augmented, from the great extension of the demand for them, occasioned by their cheapness. We see, in consequence, that in all rich manufacturing and commercial countries, the value of manufactured and commercial products bears a very high proportion to the raw products; [10] whereas, in comparatively poor countries, without much internal trade and foreign commerce, the value of their raw produce constitutes almost the whole of their wealth. If we suppose the wages of labour so to rise with the rise of produce, as to give the labourer the same command of the means of subsistence as before, yet if he is able to purchase a greater quantity of other necessaries and conveniencies, both foreign and domestic, with the price of a given quantity of corn, he may be equally well fed, clothed, and lodged, and population may be equally encouraged, although the wages of labour may not rise so high in proportion as the price of produce.
And even when the price of labour does really rise in proportion to the price of produce, which is a very rare case, and can only happen when the demand for labour precedes, or is at least quite contemporary with the demand for produce; it is so impossible that all the other outgoings in which capital is expended, should rise precisely in the same proportion, and at the same time, such as compositions for tithes, parish rates, taxes, manure, and the fixed capital accumulated under the former low prices, that a period of some continuance can scarcely fail to occur, when the difference between the price of produce and the cost of production is increased.
In some of these cases, the increase in the price of agricultural produce, compared with the cost of the instruments of production, appears from what has been said to be only temporary; and in these instances it will often give a considerable stimulus to cultivation, by an increase of agricultural profits, without showing itself much in the shape of rent. It hardly ever fails, however, to increase rent ultimately. The increased capital, which is employed in consequence of the opportunity of making great temporary profits, can seldom if ever be entirely removed from the land, at the expiration of the current leases; and, on the renewal of these leases, the landlord feels the benefit of it in the increase of his rents.
Whenever then, by the operation of the four causes above mentioned, the difference between the price of produce and the cost of the instruments of production increases, the rents of land will rise.
It is, however, not necessary that all these four causes should operate at the same time; it is only necessary that the difference here mentioned should increase. If, for instance, the price of produce were to rise, while the wages of labour, and the price of the other branches of capital did not rise in proportion, and at the same time improved modes of agriculture were coming into general use, it is evident that this difference might be increased, although the profits of agricultural stock were not only undiminished, but were to rise decidedly higher.
Of the great additional quantity of capital employed upon the land in this country, during the last twenty years, by far the greater part is supposed to have been generated on the soil, and not to have been brought from commerce or manufactures. And it was unquestionably the high profits of agricultural stock, occasioned by improvements in the modes of agriculture, and by the constant rise of prices, followed only slowly by a proportionate rise in the different branches of capital, that afforded the means of so rapid and so advantageous an accumulation.