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 dis- 
tribution 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 move- 
ment between them which brought about the equality of wages 
would bring about (probably) an unequal distribution of popula- 
tion 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 remuner- 
ation 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,