100 ON MEASURES their variations in value with regard to each other, and money would be the measure of value or medium of comparison which we employed. This is evidently using money for a measure of value in the same manner as in the first case, the only difference being that we apply it to two periods, and make a subsequent comparison of the results obtained from pach. We have therefore not yet arrived at the sense in which the term is employed by economists, who are desirous of measuring the value of commodities at different periods. They do not wish to compare the mutual value of two commodities, or the relation subsisting between two commodities at one period, with the relation subsisting between them at another period, for this would be effected by a simple reference to their prices. They state their object to be, to find some standard commodity by which they might measure the value of the same object a, at two or more different periods, or, in other words, its fluctuations in value.