ange in the same market without regard to their individual cost, it is
evident that some other principle must be discovered. Nevertheless, no
farmer will continue indefinitely the raising of a crop which brings in
the market less than a fair average return for his labor in raising it. In
a series of years he expects his wheat to return a fair compensation for
labor expended. In the same way every manufacturer expects a full return
for all cost of all his efforts, and would not continue his work from year
to year without such expectation. Moreover, when for any reason the market
value of anything is much above its cost, somebody is ready to increase
the supply of that particular article, and more will add their efforts in
the same direction until its value approaches nearly the general cost of
production as compared with the cost of other products selling in the same
market.

_Normal value._--In this way the cost of production is said to fix the
normal value of any article of commerce capable of production in
indefinite quantity and within limited time. For this reason farmers are
interested in finding the average cost of production of wheat, corn, etc.,
within a region supplying their market. They are even interested in
knowing the conditions for wheat raising in India, South Africa and
Australia, since the cost of production there may influence the value of
wheat throughout the world. The normal value of products capable of
indefinite multiplication tends always toward the value of the least
costly. This is shown in the effect of labor-saving machinery upon the
value of cloths and other goods. It is equally true in agriculture that
wheat raising upon cheap land with extensive use of machinery and
economical methods of culture and harvesting brings down the normal value.
So long as more land can be applied to wheat raising with these
advantages, the less productive methods may be too costly for the market.

On the other hand, if any production cannot be largely extended so that
the supply in market barely meets the requirements of purchasers, the
tendency of normal values is toward the cost of the most costly part of
the product required to meet wants. This is because the supply is kept up
only by the exertion of the greater amount of labor as well as the less.
If farmers in western prairie country can raise corn at an expense of 15
cents per bushel, as they can upon an average, so long as that region can
raise all the