200 
POLITICAL ECONOMY 
occupied plots from making any appreciable 
charge for them. In the absence of com 
bination on the part of landowners, no 
landowner could exact a rent larger than that 
which would induce the possessor of vacant 
land to let it. 
Next let us modify the premisses from which 
this result is deduced. Let population grow, 
and let it finally reach such a figure that the 
whole soil of quality A is absorbed in farms, 
and, in addition, recourse must be had to some 
of the soil of quality B. These conditions 
having appeared, the land of the higher 
quality will begin to bear a rent, and the rent 
will tend to amount to 10 bushels an acre, 
that is, the difference between the yield of 
the best land, 60 bushels an acre, and the 
yield of the second best, 50 bushels an acre. 
For the farm land endowed by nature in the 
lesser degree no payment can be effectively 
demanded, for reasons which have already been 
advanced to prove that in the circumstances 
first imagined no rent at all would be paid. 
Were the owners of inferior fields to insist on 
payment for their use, farmers would sub 
stitute for them land still unoccupied. But 
rent would be paid for land of higher fertility, 
because no land of this fertility remains 
unoccupied. Now, if other land is to be substi-