On the other hand, if the calculation is made upon the basis of better soils, where the average calculation does not alter the absolute surplus at all, because for them the general price of production is the limit for the investment of capital, then a quarter from the first investment of capital costs £3 and the 2 qrs from the second investment cost only £1½ each. This would thereby give rise to a grain-rent of 1 qr and a money-rent of £3 on A, but the 3 qrs would be sold for the old price of £9. If a third investment of £2½ were made under conditions of the same productiveness as the second investment, then the total would be 5 qrs for a price of production of £9. If the individual average price of production of A should remain the regulating price, then a quarter would now be sold at £1 4/5. The average price would have fallen once more — not through a new rise in productiveness of the third investment of capital, but merely through the addition of a new investment of capital having the same additional productiveness as the second. Instead of raising the rent as on the rent-bearing soils, the successive investments of capital in soil A of higher, but constant productiveness would proportionally lower the price of production and thereby, everything else being equal, the differential rent on all other soils. On the other hand, if the first investment of capital which produces 1 qr at a price of production of £3 should in itself remain regulating, then 5 qrs would be sold for £15, and the differential rent of the later investments of capital in soil A would amount to £6. The additional capital per acre of soil A, however it is applied, would be an improvement in this case, and would make the original portion of capital more productive. It would be ridiculous to say that ⅓ of the capital had produced 4 qr and the other ⅔ — 4 qrs. For £9 per acre would always produce 5 qrs, while £3 would produce only 1 qr. Whether or not a rent would arise here, whether or not a surplus-profit would be derived, would depend wholly upon the circumstances. Normally the regulating price of production would have to fall. This would be the case, if this improved but more expensive cultivation of soil A should occur only because it also takes place on the better soils, in other words, if a general revolution in agriculture should occur; so that when we now refer to the natural fertility of soil A, it is assumed that it is worked with £6 or £9 instead of £3. This would particularly apply if the bulk of cultivated acres of soil A, which furnish the main supply of a given country, should employ this new method. But if the improvement should at first extend only to a small area of A, then this better cultivated portion would yield a surplus-profit, which the landlord would be quick to transform wholly or in part into rent, and to fix in the form of rent. In this way — if the demand kept pace with the increasing supply — as more and more of soil A began to employ the new method of cultivation, rent might be gradually formed on all soil of quality A, and the surplus-productivity might be eliminated wholly or in part, depending on market conditions. The equalisation of the price of production of A to the average price of its produce obtained under conditions of increased outlay of capital might thus be prevented by fixing the surplus-profit of this increased investment of capital in the form of rent. Thus, as was previously seen to be the case for the better soils when the productiveness of the additional capital decreased, it would again be the transformation of surplus-profit into ground-rent, i.e., the intervention of property in land, which would raise the price of production, instead of the differential rent merely being the result of the difference between the individual and the general price of production. It would prevent, in the case of soil A, the coincidence of both prices because it would interfere with the regulation of the price of production by the average price of production on A; it would thus maintain a higher price of production than necessary and thereby create rent. Even if grain were freely imported from abroad, the same result could be brought about or perpetuated by compelling farmers to use soil capable of competing in grain cultivation without yielding rent, at the price of production regulated from abroad, for other purposes, e.g., pasturage, so that only rent-bearing soils would be used for grain cultivation, i.e., only soils whose individual average price of production per quarter were below that determined from abroad. On the whole, it is to be assumed that in the given case, the price of production will fall, but not to the level of its average; it will be higher than the average, but below the price of production of the worst cultivated soil A, so that the competition from new soil A is limited.