discovery of mines in America. On the other hand, if he should see the price of wheat double from one year to the next without any remarkable variation in the price of most other articles or in their relative values, he would attribute it to an absolute change in the value of wheat, even if he did not know that a bad grain harvest had preceded the high price.
Without reference to this extreme case, where the disturbance of the system of relative values is explained by the movement of a single article, it is evident that among all the possible hypotheses on absolute variations some explain the relative variations more simply and more probably than others.
If, without being limited to consideration of the system of relative values at two distinct periods, observation follows it through its intermediate states, a new set of data will be provided to determine the most probable law of absolute variations, from all possibihties for satisfying the observed law of relative variations.
be the values of certain articles, with reference to a gram of silver; if the standard of value is changed and a myriagram of wheat is substituted for the gram of silver, the values of the same articles will be given by the expressions
a being the price of the myriagram of wheat, or its value with reference to a gram of silver. In general, whenever it