ABSOLUTE DIFFERENCES IN COST 17

This last supposition is in accord with what we should expect to
find, and in the main do find, in trade within the bounds of a
homogeneous country — in domestic trade. If we suppose the
two regions to be, for example, New York and Pennsylvania,
equality of money wages may be expected, and thereby equality
of gain from the trade between them. Marked divergence from
such equality would lead to a movement of population from one
to the other, and eventually to an equal sharing of the gain. This
result is dependent, it need hardly be said, on effective homogeneity
between the peoples of the two regions ; the inhabitants of both are
able and willing to move as freely between the regions as within
them, and can apply their labor as effectively in the one as in the
other.
It is hardly necessary to point out that such an equal sharing of
gain, with equality in money wages, does not imply an equal distribution
 of population between the two regions. New York or
Pennsylvania might have very different numbers. That one of
them which produced the commodities most in demand would have
the larger population; the other would have the smaller. The
volume of output both for copper (say) in Pennsylvania and for
linen in New York would adjust itself to the conditions of demand
for these articles in the two states, and the distribution of workers
between them would adjust itself accordingly. The free movement
 between them which brought about the equality of wages
would bring about (probably) an unequal distribution of population
 and a distribution shifting with changes in demand. It is
the absence of free movement, and the consequent fixity of each
population, that causes something other than equality of remuneration
 to determine the share which each region shall secure of the
possible gain from trade. That other factor, as will appear in the
sequel, is the state of demand in the two countries for their several
products.
The type of international trade considered in this chapter — that
in which there are absolute differences in cost — is found mainly in
the trade between tropical and temperate countries. The tropical
countries have an absolute advantage, because of climatic conditions,