_The Source of the Fund for Repairs and Renewals._--The fund for repairs and renewals must, of course, like the net income itself, be furnished by instruments that are above the no-rent grade. A machine will naturally be used as long as it pays anything whatever, and during the latter part of its career it usually produces less than mere interest on its cost. So long as the labor and the auxiliary capital that are combined with the instrument produce by its aid any more than they would produce if they were withdrawn from it and added, as marginal increments, to the labor and capital that are working in connection with good instruments, they will continue to use the machine and they will abandon it only when it ceases to pay anything whatever. Out of the total amount it produces before reaching this point of abandonment comes the amount that is needed as an offset for the cost of providing a new machine. _Incorrectness of a Common Statement concerning Rent and Price._--This brings into view a striking fallacy of what has been current economic theory. It has been customary to claim that the rent of land "is not an element in price," although the interest on capital is such an element. The rent of land is the net product of land; and if interest be kept distinct from it, this income is the net product of a permanent stock of capital goods. The relations of these two component parts of the constant output of goods to the prices of the goods are identical. _Proof of the Incorrectness of the Current Statement concerning Rent and Price._--The vague form of the current statement concerning rent and price is responsible for much confusion of thought on that subject. What the statement would mean is that the price of wheat is not affected by the great contributions to the supply of it which good lands are making. These contributions are the rent in its original form. The rent of wheat land is wheat, that of cotton land is cotton, that of mill sites is manufactured goods, etc. That money is used in payments made to landlords changes nothing that is essential. To say that such contributions to the supply of particular commodities are not an element in determining the prices of them, would be as unreasonable as to make the same assertion concerning other parts of the supply. Quite as logically might it be asserted that other components in the supply do not affect prices--that the amount of wheat which is attributable to harvesting machinery or the amount of calico which is imputable to looms has no influence in the market values of these articles.