OF VALUE.

(13

It may be objected, ¢ Yes, good enough for
commodities at each time, but not between
commodities at different times.”
This objection, however, proceeds on a fundamental
 mistake already exposed in a former
chapter, namely, that the relation of value can
exist between commodities at different periods,
which is in the nature of the case impossible;
and if no relation exists there canbe no measurement
 of it. Itis, in truth, only the value of
commodities at the same time that can be measured
 ; another point in which the supposed
analogy between the measurement of space
and of value completely fails. In the case
of length, a direct comparison may be made
between two objects, however separated by
time, and their ratio to each other found. The
length of an object now may be compared with
the length of an object in former times, by
means of an instrument actually handed down
to us ; by an uninterrupted transmission of the
same object, or the same space through the
medium of different objects, furnishing a com-