But the cost of production is not a constant and accurate measure of the value of artificial capital. The true measure is found in the revenue or interest that a given piece of capital yields to its owners. If the current rate of interest is five per cent., a factory that brings in ten thousand dollars net return will have a value of about two hundred thousand dollars. This is the governing factor of value from the side of demand. In a no-interest economy the demand factor would be quite different. Capital instruments would be in demand, not as revenue producers, but as the concrete embodiments, the indispensable requisites of saving and accumulation. For it is impossible that saving should in any considerable amount take the form of cash hoards. In the words of Sir Robert Giffen: "The accumulations of a single year, even taking it at one hundred and fifty millions only, ... would absorb more than the entire metallic currency of the country [Great Britain]. They cannot, therefore, be made in cash."[142] The instruments of production would be sought and valued by savers for the same reason that safes and safety deposit boxes are in demand now. They would be the only means of carrying savings into the future, and they would necessarily bring a price sufficiently high to cover the cost of producing them. One man might deposit his savings in a bank, whence they would be borrowed without interest by some director of industry. When the owner of the savings desired to recover them he could obtain from the bank the fund of some other depositor, or get the proceeds of the sale of the concrete capital in which his own savings had been embodied. Another man might prefer to invest his savings directly in a building, a machine, or a mercantile business, whence he could recover them later from the sale of the property. Hence the absence of interest would not change essentially the processes of saving or investment. Capital would still have value, but its valuation from the demand side would rest on a different basis. It would be valued not in proportion to its power to yield interest, but because of its capacity to become a receptacle for savings, and to carry into the future the consuming power of the present.