as a demand, would at the present time effectuate the supply of the same quantity of a commodity produced by labour alone, as an equal weight of silver would have effectuated under similar circumstances in the reign of Edward III.; since which period the value of silver, as compared with labour, has fallen five or six times.
Under any changes, however, which may take place in money, if the conditions of the supply of any commodity, or the elementary costs of its production, require a certain quantity of labour of a given description, the power of setting to work that quantity of labour, whether paid for by a larger or smaller quantity of produce or money, will be an effectual demand for it. Now it is obvious that this cannot be said of any product of labour whatever.
In the first place, there is no product of labour which is the sole condition of the supply of any one commodity. Consequently, while the necessary conditions of the supply of any commodity are a given quantity of labour of a certain description, no given quantity of any product of labour can continue, like a given quantity of labour itself, always to represent the same effectual demand for such commodity.
Secondly, there is no product of labour, which, applied directly, enters, as labour itself does, into the composition of all commodities that have value, and constitutes the chief element in the conditions of their supply. Consequently there is no product of labour which can represent the most important condition of the supply of all commodities, namely the quantity of labour absolutely necessary to their production; and we cannot say that a definite quantity of money, a definite quantity of corn, a definite quantity of cloth, or a definite quantity of any product of labour, subject, as they all are, to variations in their relation to labour, can continue to afford an effectual demand for that definite quantity of labour, without which the mass of commodities cannot by possibility be produced.
But if, when commodities are selling at their natu-
