otton goods that his presence and labor in the mill insure. In
raising crops, therefore, the Englishman is at a more serious
disadvantage in comparison with the American. The fact is expressed in
a practical way by saying that the English labor is cheaper and is
therefore more available for making things that are exported to the
distant markets of the world than is labor of the same kind in
America; but the reason for this cheapness is primarily the land
crowding, which reduces the productive power of a final unit of labor
in the former country. Because the man cannot get for himself many
bushels of wheat per annum by working on land he can afford to work in
a mill at a rate corresponding with the value of the produce he could
secure as a cultivator.[3]

[3] In this connection see the discussion of the principles
of international trade in J. S. Mill's "Principles of
Political Economy," Book III, Chapter XVI.

_General Differences between the Condition of Densely Peopled Regions
and that of Sparsely Peopled Ones._--In a very general way it may be
said that the comparative amount of manufacturing should naturally
vary directly with density of population, and that the comparative
amount of agriculture should vary inversely to it. In computing
density due regard must, as has been indicated, be paid to the quality
of the land as well as the area, since a number of inhabitants which
would unduly congest a sterile agricultural region can be well
maintained on a fertile one. In the accompanying figure the line _AD_
inclosed by the vertical lines represents the part of the earth which
we have called central, and the left side of it is the part of this
area which has the sparsest population, while the right side is that
which has the densest. The rising line _BC_ represents the varying
density of the population in different parts of the broad area we
regard as general economic society, the dotted line _EF_ may be taken
as expressing the increase in the part of the labor and capital of the
country devoted to manufacturing as population becomes denser, _AE_
measures the proportionate number of persons engaged in manufacturing
in the region of sparsest population, and _DF_ measures the
comparative number in the region most densely peopled.

[Illustration]

_AG_ and _DH_ represent the numbers engaged in agriculture in the two
regions, and the descent of the line _GH_ represents the predominance
of agriculture in the