not be grown on the same soil at all, the value of each would be determined by its peculiar cost of production on the least favourable of the soils adapted for it which the existing demand required a recourse to. The fact, however, is that both wheat and oats can be grown on almost any soil which is capable of producing either: but some soils, such as the stiff clays, are better adapted for wheat, while others (the light sandy soils) are more suitable for oats. There might be some soils which would yield, to the same quantity of labour, only four quarters of oats to three of wheat; others perhaps less than three of wheat to five quarters of oats. Among these diversities, what determines the relative value of the two things?
It is evident that each grain will be cultivated in preference, on the soils which are better adapted for it than for the other; and if the demand is supplied from these alone, the values of the two grains will have no reference to one another. But when the demand for both is such as to require that each should be grown not only on the soils peculiarly fitted for it, but on the medium soils which, without being specifically adapted to either, are about equally suited for both, the cost of production on those medium soils will determine the relative value of the two grains; while the rent of the soils specifically adapted to each, will be regulated by their productive power, considered with reference to that one alone to which they are peculiarly applicable. Thus far the question presents no difficulty, to any one to whom the general principles of value are familiar.
It may happen, however, that the demand for one of the two, as for example wheat, may so outstrip the demand for the other, as not only to occupy the soils specially suited for wheat, but to engross entirely those equally suitable to both, and even encroach upon those which are better adapted to oats. To create an inducement for this unequal apportionment of the cultivation, wheat must be relatively dearer, and oats cheaper, than according to the cost of their production
